[Federal Register Volume 69, Number 160 (Thursday, August 19, 2004)]
[Notices]
[Pages 51507-51544]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-18905]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration


Announcement of FAA Advisory Circular (AC) 120-27D, Aircraft 
Weight and Balance Control

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of availability of AC, and request for comments.

-----------------------------------------------------------------------

SUMMARY: This notice announces the availability of and requests 
comments on AC 120-27D, which provides guidance on the requirements for 
maintaining an aircraft weight and balance control program.

DATES: Submit comments on or before September 17, 2004.

ADDRESSES: Send all maintenance-related comments on AC 120-27D to Mr. 
Darcy D. Reed, Aircraft Maintenance Division, Air Carrier Maintenance 
Branch (AFS-330), Federal Aviation Administration, 800 Independence 
Ave., SW., Washington, DC 20591; facsimile (202) 267-5115; e-mail 
[email protected]. Send all operations-related comments on AC 120-
27D to Mr. Dennis Pratte, Air Transportation Division, Air Carrier 
Operations Branch (AFS-220), Federal Aviation Administration, 800 
Independence Ave., SW., Washington, DC 20591; facsimile (202) 267-5229; 
e-mail [email protected].

FOR FURTHER INFORMATION CONTACT: Mr. Darcy D. Reed, AFS-330, at the 
address, facsimile, or e-mail listed above, or by telephone at (202) 
267-9948; or Mr. Dennis Pratte, AFS-220, at the address, facsimile, or 
e-mail listed above, or by telephone at (202) 267-5488.

SUPPLEMENTARY INFORMATION:

Comments Invited

    AC 120-27D is available on the FAA's Regulatory Guidance Library 
Web site at http://www.airweb.faa.gov/rgl, under the Advisory Circulars 
link. Interested persons are invited to comment on the AC by submitting 
written data, views, or suggestions, as they may desire. Please 
identify AC 120-27D, Aircraft Weight and Balance Control, and submit 
comments, either hardcopy or electronic, to the appropriate address 
listed above. Comments may be inspected at the above address between 9 
a.m. and 4 p.m. weekdays, except Federal holidays.

    Issued in Washington, DC, on August 11, 2004.
John M. Allen,
Deputy Director, Flight Standards Service.
BILLING CODE 4910-13-P

[[Page 51508]]

[GRAPHIC] [TIFF OMITTED] TN19AU04.000

BILLING CODE 4910-13-C

Table of Contents

Chapter 1. Introduction
    100. What is the purpose of this advisory circular (AC)?
    101. How is this AC organized?

[[Page 51509]]

    102. What documents does this AC cancel?
    103. What should an operator consider while reading this AC?
    104. Who should use this AC?
    Table 1-1. Aircraft Cabin Size
    105. Who can use standard average or segmented weights?
Chapter 2. Aircraft Weights and Loading Schedules
    Section 1. Establishing Aircraft Weight
    200. How does an operator establish the initial weight of an 
aircraft?
    201. How does an operator document changes to an aircraft's 
weight and balance?
    Table 2-1. Incremental Weight Changes that Should Be Recorded in 
a Weight and Balance Change Record
    202. How does the operator maintain the OEW?
    203. How often are aircraft weighed?
    Table 2-2. Number of Aircraft to Weigh in a Fleet
    204. What procedures should be used to weigh aircraft?
    Section 2. Aircraft Loading Schedules
    205. What is a loading schedule?
    206. How should an operator determine the weight of each fluid 
used aboard the aircraft?
    Section 3. Constructing a Loading Envelope
    207. What should an operator consider when constructing a 
loading envelope?
    208. What information from the aircraft manufacturer should an 
operator use?
    209. What should the operator consider when curtailing the 
manufacturer's loading envelope?
    210. What are some examples of common curtailments to the 
manufacturer's loading envelope?
    Section 4. Automated Weight and Balance Systems
    211. How does an onboard weight and balance system compare to a 
conventional weight buildup method?
    212. What measures should an operator take to obtain operational 
approval for an onboard weight and balance system?
    213. What operational considerations should an operator take 
into account when using an onboard weight and balance system?
    214. May an operator use the information in this AC to develop a 
backup system?
    215. What operational considerations should an operator take 
into account when using a computerized weight and balance system?
Chapter 3. Methods to Determine the Weight of Passengers and Bags
    Section 1. Choosing the Appropriate Method
    300. What should an operator consider when choosing the 
appropriate method?
    Section 2. Standard Average Weights
    301. What standard average passenger weights should an operator 
with an approved carry-on bag program use?
    Table 3-1. Standard Average Passenger Weights
    302. What standard average weights should an operator use for 
carry-on bags and personal items?
    303. What standard average weights should an operator use for 
checked bags?
    304. What standard average weight should an operator of large 
cabin aircraft use for bags checked plane-side?
    305. What standard average weights should an operator of small 
and medium cabin aircraft use, if it has a ``no-carry-on bag 
program?''
    Table 3-2. Average Passenger Weights for Operators with a No-
Carry-on Bag Program
    306. What are the standard average weights for crewmembers?
    Table 3-3. Standard Crewmember Weights
    307. What weights may be used for company materials and mail?
    308. What are the standard average weights for special passenger 
groups that do not fit an operator's standard average weight 
profile?
    Section 3. Average Weights Based on Survey Results
    309. What should an operator consider when designing a survey?
    310. What sample sizes should an operator use?
    Table 3-4. Minimum Sample Sizes
    311. When conducting a survey, can an operator collect a smaller 
sample size than that published in Table 3-4?
    312. What sampling method should an operator use?
    313. What should an operator consider when developing a survey 
plan and submitting it to the FAA?
    314. What general survey procedures should an operator use?
    315. What information might an operator gain from conducting a 
count survey?
    316. When should an operator conduct another survey to 
revalidate the data from an earlier survey?
    Section 4. Segmented Passenger Weights
    317. What should an operator consider when using segmented 
weights?
    Table 3-5. Segmented Weights for Adult Passengers (in Pounds; 
Summer)
    318. How are loading envelope curtailment and bag weight 
affected by an operator's use of segmented weights?
    319. What might be an example of an operator using the segmented 
weights in Table 3-5?
    Section 5. Actual Weight Programs
    320. If the operator decides to use an actual weights program, 
how might it determine the actual weight of passengers?
    321. If the operator decides to use an actual weight program, 
how should it determine the actual weights of personal items and 
bags?
    322. What approach should an operator use to record actual 
weights?
Chapter 4. Operator Reporting Systems and FAA Oversight
    Section 1. Pilot and Agent Reporting Systems
    400. What are the pilots' and operators' responsibilities in 
reporting aircraft loading and manifest preparation discrepancies?
    Section 2. FAA Oversight
    401. Which FAA inspectors are responsible for overseeing an 
operator's weight and balance program?
    402. Which portions of OpSpecs or MSpecs are relevant to an 
operator's weight and balance program?
    403. When will the FAA revise the standard average weights in 
this AC?
Appendix 1. Definitions
Appendix 2. Source of Standard Average Weights in This AC
    1. Standard average passenger weights.
    2. Standard average bag weights.
    Table 2-1. Bag Survey Results
Appendix 3. Sample Operational Loading Envelope
    1. Introduction.
    2. Assumptions for this example.
    Figure 3-1. Sample Aircraft Interior Seating Diagram
    3. Curtailments for passenger seating variation.
    Table 3-1. Calculation of Zone 1 Centroid
    Table 3-2. Calculation of Zone 2 Centroid
    Table 3-3. Calculation of Zone 3 Centroid
    Table 3-4. Moments Resulting from the Zone Centroid Assumption 
for Zone 1
    Table 3-5. Moments Resulting from the Window-Aisle-Remaining 
Assumption for Zone 1
    Table 3-6. Comparison of Moments for Zone 1
    Table 3-7. Moments Resulting from the Zone Centroid Assumption 
for Zone 2
    Table 3-8. Moments Resulting from the Window-Aisle-Remaining 
Assumption for Zone 2
    Table 3-9. Comparison of Moments for Zone 2
    Table 3-10. Moments Resulting from the Zone Centroid Assumption 
for Zone 3
    Table 3-11. Moments Resulting from the Window-Aisle-Remaining 
Assumption for Zone 3
    Table 3-12. Comparison of Moments for Zone 3
    4. Other curtailments to the manufacturer's loading envelope.
    5. Operational loading envelope diagrams.
    Figure 3-2. Operational Loading Envelope with a Curtailment for 
Variations in Passenger Seating
    Figure 3-3. Operational Loading Envelope Using Actual Seating 
Location of Passengers
Appendix 4. Additional Curtailments to CG Envelopes to Account for 
Variations to Passenger Weights
    Table 4-1. Row Factor
    Table 4-2. Sample Curtailment Due to Variations in Passenger 
Weight and Male/Female Ratio Using Window-Aisle Method
Appendix 5. Options to Improve Accuracy
    Figure 5-1. Sample Aircraft Interior Seating Diagram
    Figure 5-2. Sample Passenger Seating Moment
    Figure 5-3. Sample Passenger Seating Moment
    Figure 5-4. Sample Passenger Seating Moment
Appendix 6. Sample CG Envelope Development
    Figure 6-1. Operational CG Envelope--3 Passenger Cabin Zones
    Figure 6-2. Operational CG Envelope--Actual Passenger Seating
Appendix 7. Checklist

[[Page 51510]]

Chapter 1. Introduction

100. What Is the Purpose of This Advisory Circular (AC)?

    a. This AC provides operators with guidance on how to develop and 
receive approval for a weight and balance control program for aircraft 
operated under Title 14 of the Code of Federal Regulations (14 CFR) 
part 91, subpart K of part 91, and parts 121, 125, and 135.
    b. This AC presents recommendations for an acceptable means, but 
not the only means, to develop and receive approval for a weight and 
balance control program, and includes guidance for using average and 
estimated weights in accordance with part 121, section 121.153(b) and 
other applicable parts of subpart K of part 91 and parts 121, 125, and 
135.

    Note: Per part 125, section 125.91(b), no person may operate an 
airplane in a part 125 operation unless the current empty weight and 
center of gravity (CG) are calculated from the values established by 
actual weighing of the airplane within the preceding 36 calendar-
months.

    c. If an operator adopts the suggestions contained in this AC, the 
operator must ensure that, when appropriate, it replaces discretionary 
language such as ``should'' and ``may'' with mandatory language in 
relevant manuals, operations specifications (OpSpecs), or management 
specifications (MSpecs).

101. How Is This AC Organized?

    This AC has four main chapters and seven appendixes. Chapter 1 
contains general information about this AC and background. Chapter 2 
addresses aircraft weighing and loading schedules. Chapter 3 describes 
different methods to determine the weight of passengers and bags. 
Chapter 4 addresses the Federal Aviation Administration's (FAA) role in 
developing and approving an operator's weight and balance control 
program. Finally, appendixes 1 through 7 contain technical information 
such as definitions, the source of data used in the AC, a sample 
loading envelope, an example of curtailments to the loading envelope, 
suggestions to improve accuracy, sample CG envelope development, and 
checklists for operators.

102. What Documents Does This AC Cancel?

    This AC cancels--
    a. AC 120-27C, Aircraft Weight and Balance Control, dated November 
7, 1995; and
    b. Joint Handbook Bulletin for Airworthiness (HBAW) 95-14 and Air 
Transportation (HBAT) 95-15, Adherence to Advisory Circular 120-27C, 
``Aircraft Weight and Balance Control,'' dated November 17, 1995.

103. What Should an Operator Consider While Reading This AC?

    a. Accurately calculating an aircraft's weight and CG before flight 
is essential to comply with the certification limits established for 
the aircraft. These limits include both weight and CG limits. By 
complying with these limits and operating under the procedures 
established by the manufacturer, an operator is able to meet the weight 
and balance requirements specified in the aircraft flight manual (AFM). 
Typically, an operator calculates takeoff weight by adding the 
operational empty weight (OEW) of the aircraft, the weight of the 
passenger and cargo payload, and the weight of fuel. The objective is 
to calculate the takeoff weight and CG of an aircraft as accurately as 
possible.
    b. When using average weights for passengers and bags, the operator 
must be vigilant to ensure that the weight and balance control program 
reflects the reality of aircraft loading. The FAA will periodically 
review the guidance in this AC and update this AC if average weights of 
the traveling public should change or if regulatory requirements for 
carry-on bags or personal items should change. Ultimately, the operator 
is responsible for determining if the procedures described in this AC 
are appropriate for use in its type of operation.

104. Who Should Use This AC?

    a. This document provides guidance to operators that are either 
required to have an approved weight and balance control program under 
parts 121 and 125, or choose to use average aircraft, passenger or 
baggage weights when operating under subpart K of part 91 or part 135. 
The guidance in this AC is useful for anyone involved in developing or 
implementing a weight and balance control program.
    b. As shown in Table 1-1, the FAA has divided aircraft into three 
categories for this AC to provide guidance appropriate to the size of 
the aircraft.

                     Table 1-1.--Aircraft Cabin Size
------------------------------------------------------------------------
 For this AC, an aircraft originally type-
            certificated with--                    Is considered--
------------------------------------------------------------------------
71 or more passenger seats................  A large-cabin aircraft.
30 to 70 passenger seats..................  A medium-cabin aircraft.
5 to 29 passenger seats...................  A small-cabin aircraft.
0 to 4 passenger seats....................  Not eligible.
------------------------------------------------------------------------

105. Who Can Use Standard Average or Segmented Weights?

    a. Standard Average Weights. Use of standard average weights is 
limited to operators of multiengine turbine-powered aircraft originally 
type-certificated for five (5) or more passenger seats who hold a 
letter of authorization (LOA), OpSpecs, or MSpecs, as applicable, and 
were certificated under 14 CFR part 25, 29, or part 23 commuter 
category or the operator and manufacturer is able to prove that the 
aircraft can meet the performance requirements of subpart B of part 25. 
Single-engine and multiengine turbine Emergency Medical Service 
Helicopter (EMS/H) operators may use standard average weights for EMS 
operations, provided they have received an LOA.
    b. Segmented Weights. Use of segmented weights is limited to those 
aircraft that meet the requirements of paragraph 105(a) or that are 
multiengine turbine-powered aircraft originally type-certificated for 
five (5) or more passenger seats and that do not meet the performance 
requirements of subpart B of part 25. Segmented passenger weights are 
listed in Chapter 3, Table 3-5.

Chapter 2. Aircraft Weights and Loading Schedules

Section 1. Establishing Aircraft Weight

200. How Does an Operator Establish the Initial Weight of an Aircraft?
    Prior to being placed into service, each aircraft should be weighed 
and the empty weight and CG location established. New aircraft are 
normally weighed at the factory and are eligible to be placed into 
operation without reweighing if the weight and balance records were 
adjusted for alterations and modifications to the aircraft and if the 
cumulative change to the weight and balance log is not more than plus 
or minus one-half of one percent (0.5 percent) of the maximum landing 
weight or the cumulative change in the CG position exceeds one-half of 
one percent (0.5 percent) of the mean aerodynamic chord. Aircraft 
transferred from one operator that has an approved weight and balance 
program, to another operator with an approved program, need not be 
weighed prior to use by the

[[Page 51511]]

receiving operator unless more than 36 calendar-months have elapsed 
since last individual or fleet weighing, or unless some other 
modification to the aircraft warrants that the aircraft be weighed 
(e.g., paragraph 203(c)). Aircraft transferred, purchased, or leased 
from an operator without an approved weight and balance program, and 
that have been unmodified or only minimally modified, can be placed 
into service without being reweighed if the last weighing was 
accomplished by a method established through an operator's approved 
weight and balance control program within the last 12 calendar-months 
and a weight and balance change record was maintained by the operator. 
See paragraph 203(c) for a discussion of when it may be potentially 
unsafe to fail to reweigh an aircraft after it has been modified.
201. How Does an Operator Document Changes to an Aircraft's Weight and 
Balance?
    The weight and balance system should include methods, such as a 
log, ledger, or other equivalent electronic means by which the operator 
will maintain a complete, current, and continuous record of the weight 
and CG of each aircraft. Alterations and changes affecting either the 
weight and/or balance of the aircraft should be recorded in this log. 
Changes to an aircraft that result in a weight being added to the 
aircraft, weight being removed from the aircraft, or weight being 
relocated in or on the aircraft should be recorded in such a log. 
Changes in the amount of weight or in the location of weight in or on 
the aircraft should be recorded whenever the weight change is at or 
exceeds the weights listed in Table 2-1.

   Table 2-1.--Incremental Weight Changes That Should Be Recorded in a
                    Weight and Balance Change Record
------------------------------------------------------------------------
                                              An operator should record
    In the weight change record of a--         any weight changes of--
------------------------------------------------------------------------
Large-cabin aircraft......................  +/-10 lb or greater.
Medium-cabin aircraft.....................  +/-5 lb or greater.
Small-cabin aircraft......................  +/-1 lb or greater.
------------------------------------------------------------------------

202. How Does the Operator Maintain the OEW?
    The loading schedule may utilize the individual weight of the 
aircraft in computing operational weight and balance or the operator 
may choose to establish fleet empty weights for a fleet or group of 
aircraft.
    a. Establishment of OEW. The OEW and CG position of each aircraft 
should be reestablished at the reweighing periods discussed in 
paragraph 203. In addition, it should be reestablished whenever the 
cumulative change to the Weight and Balance Log is more than plus or 
minus one-half of 1 percent (0.5 percent) of the maximum landing 
weight, or whenever the cumulative change in the CG position exceeds 
one-half of 1 percent (0.5 percent) of the mean aerodynamic chord 
(MAC). In the case of helicopters and airplanes that do not have a MAC-
based CG envelope (e.g., canard equipped airplane), whenever the 
cumulative change in the CG position exceeds one-half of 1 percent (0.5 
percent) of the total CG range, the weight and balance should be 
reestablished.
    b. Fleet Operating Empty Weights (FOEW). An operator may choose to 
use one weight for a fleet or group of aircraft if the weight and CG of 
each aircraft is within the limits stated above for establishment of 
OEW. When the cumulative changes to an aircraft Weight and Balance Log 
exceed the weight or CG limits for the established fleet weight, the 
empty weight for that aircraft should be reestablished. This may be 
done by moving the aircraft to another group, or reestablishing new 
FOEWs.
203. How Often Are Aircraft Weighed?
    a. Individual Aircraft Weighing Program. Aircraft are normally 
weighed at intervals of 36 calendar-months. An operator may, however, 
extend this weighing period for a particular model aircraft when 
pertinent records of actual routine weighing during the preceding 
period of operation show that weight and balance records maintained are 
sufficiently accurate to indicate that aircraft weights and CG 
positions are within the cumulative limits specified for establishment 
of OEW, (see paragraph 202). Such applications should be substantiated 
in each instance with at least two aircraft weighed. Under an 
individual aircraft weighing program, an increase should not be granted 
which would permit any aircraft to exceed 48 calendar-months since the 
last weighing, including when an aircraft is transferred from one 
operator to another. In the case of helicopters, increases should not 
exceed a time that is equivalent to the aircraft overhaul period.

    Note: Per part 125, section 125.91(b), no person may operate an 
airplane in a part 125 operation, unless the current empty weight 
and center of gravity (CG) are calculated from the values 
established by actual weighing of the airplane within the preceding 
36 calendar-months.

    b. Fleet Weighing. An operator may choose to weigh only a portion 
of the fleet and apply the unaccounted weight and moment change 
determined by this sample to the remainder of the fleet.
    (1) A fleet is composed of a number of aircraft of the same model 
(For example, B747-200s in a passenger configuration and B747-200 
freighters should be considered different fleets. Likewise, B757-200s 
and B757-300s should be considered different fleets). The primary 
purpose of defining a fleet is to determine how many aircraft should be 
weighed in each weighing cycle. A fleet may be further divided into 
groups to establish FOEWs.

           Table 2--2. Number of Aircraft To Weigh in a Fleet
------------------------------------------------------------------------
                                             An operator must weigh (at
              For fleets of--                        minimum)--
------------------------------------------------------------------------
1 to 3 aircraft...........................  All aircraft.
4 to 9 aircraft...........................  3 aircraft, plus at least 50
                                             percent of the number of
                                             aircraft greater than 3.
More than 9 aircraft......................  6 aircraft, plus at least 10
                                             percent of the number of
                                             aircraft greater than 9.
------------------------------------------------------------------------

    (2) In choosing the aircraft to be weighed, the aircraft in the 
fleet having the most hours flown since last weighing should be 
selected.
    (3) An operator should establish a time limit such that all 
aircraft in a fleet are eventually weighed. Based on the length of time 
that a fleet of aircraft typically remains in service with an operator, 
the time limit should not exceed 18 years (six 3-year weighing cycles). 
It is not intended that an operator be required to weigh any remaining 
aircraft in the event that business conditions result in retirement of 
a fleet before all aircraft have been weighed.
    c. Weighing Aircraft--Modifications. For most aircraft 
modifications, computing the weight and balance changes is practical. 
For some modifications, such as interior reconfigurations, the large 
number of parts removed, replaced, and installed make an accurate 
determination of the weight and balance change by computation 
impractical. It would be potentially unsafe to fail to reestablish the 
aircraft weight and balance, by actually reweighing the aircraft, in 
situations where the cumulative net change in the weight and balance 
log exceeds:
    (1) In the case of airplanes, plus or minus one-half of 1 percent 
(0.5

[[Page 51512]]

percent) of the maximum landing weight, or whenever the cumulative 
change in the CG position exceeds one-half of 1 percent (0.5 percent) 
of the MAC.
    (2) In the case of helicopters and airplanes that do not have a 
MAC-based CG envelope (e.g., canard equipped airplane), whenever the 
cumulative change in the CG position exceeds one-half of 1 percent (0.5 
percent) of the total CG range.

    Note: In the situations specified in paragraphs 203c(1) and (2), 
the operator should weigh two or more aircraft in a fleet, as 
required in Table 2-2, to get consistent results. The operator may 
choose to weigh the aircraft before and after the modification, or 
just after the modification.

204. What Procedures Should Be Used to Weigh Aircraft?
    a. An operator should take precautions to ensure that it weighs an 
aircraft as accurately as possible. These precautions include checking 
to ensure that all required items are aboard the aircraft and the 
quantity of all fluids aboard the aircraft is considered. An operator 
should weigh aircraft in an enclosed building because scale readings 
stabilize faster in the absence of drafts from open doors.
    b. An operator should establish and follow instructions for 
weighing the aircraft that are consistent with the recommendations of 
the aircraft manufacturer and scale manufacturer. The operator should 
ensure that all scales are certified and calibrated by the manufacturer 
or a certified laboratory, such as a civil department of weights and 
measures, or the operator may calibrate the scale under an approved 
calibration program. The operator should also ensure that the scale is 
calibrated within the manufacturer's recommended time period, or time 
periods, as specified in the operator's approved calibration program.

Section 2. Aircraft Loading Schedules

205. What is a Loading Schedule?
    a. The loading schedule is used to document compliance with the 
certificated weight and balance limitations contained in the 
manufacturer's AFM and weight and balance manual.
    b. The loading schedule is developed by the operator based on its 
specific loading calculation procedures and provides the operational 
limits for use with the operator's weight and balance program approved 
under this AC. These approved operational limits are typically more 
restrictive but do not exceed the manufacturer's certificated limits. 
This is because the loading schedule is generally designed to check 
only specific conditions (e.g., takeoff and zero fuel) known prior to 
takeoff, and must account for variations in weight and balance in 
flight. It must also account for factors selected to be excluded, for 
ease of use, from the calculation process. Loading the aircraft so that 
the calculated weight and balance is within the approved limits will 
maintain the actual weight and balance within the certificated limits 
throughout the flight.
    c. Development of a loading schedule represents a trade-off between 
ease of use and loading flexibility. A schedule can provide more 
loading flexibility by requiring more detailed inputs, or it can be 
made easier to use by further limiting the operational limits to 
account for the uncertainty caused by the less detailed inputs.
    d. Several types of loading schedules are commonly-used, including 
computer programs as well as ``paper'' schedules, which can be either 
graphical, such as an alignment (``chase around chart'') system, slide 
rule, or numerical, such as an adjusted weight or index system.
    e. It is often more convenient to compute the balance effects of 
combined loads and to display the results by using ``balance units'' or 
``index units.'' This is done by adding the respective moments (weight 
times arm) of each item. Graphing the moments results in a ``fan grid'' 
where lines of constant balance arms (BA) or % MAC are closer together 
at lower weights and further apart at higher weights. Direct graphical 
or numerical addition of the balance effects are possible using these 
moment values.
    f. To make the magnitude of the numbers more manageable, moments 
can be converted to an index unit. For example:
[GRAPHIC] [TIFF OMITTED] TN19AU04.001


    Note: Where datum is the reference BA that will plot as a 
vertical line on the fan grid, M and K are constants that are 
selected by the operator. M is used to scale the index values, and K 
is used to set the index value of the reference BA.

206. How Should an Operator Determine the Weight of Each Fluid Used 
Aboard the Aircraft?
    An operator should use one of the following:
    a. The actual weight of each fluid,
    b. A standard volume conversion for each fluid, or
    c. A volume conversion that includes a correction factor for 
temperature.

Section 3. Constructing a Loading Envelope

207. What Should an Operator Consider When Constructing a Loading 
Envelope?
    Each operator complying with this AC must construct a ``loading 
envelope'' applicable to each aircraft being operated. The envelope 
will include all relevant weight and balance limitations. It will be 
used to ensure that the aircraft is always operated within appropriate 
weight and balance limitations, and will include provisions to account 
for the loading of passengers, fuel, and cargo; the in-flight movement 
of passengers, aircraft components, and other loaded items; and the 
usage or transfer of fuel and other consumables. The operator must be 
able to demonstrate that the aircraft is being operated within its 
certificated weight and balance limitations using reasonable 
assumptions that are clearly stated.
208. What Information From the Aircraft Manufacturer Should an Operator 
Use?
    The construction of the loading envelope will begin with the weight 
and balance limitations provided by the aircraft manufacturer in the 
weight and balance manual, type certificate data sheet, or similar 
approved document. These limitations will include, at minimum, the 
following items, as applicable:

a. Maximum zero-fuel weight.
b. Maximum takeoff weight.
c. Maximum taxi weight.
d. Takeoff and landing CG limitations.
e. In-flight CG limitations.
f. Maximum floor loadings-including both running and per square foot 
limitations.
g. Maximum compartment weights.
h. Cabin shear limitations.
i. Any other limitations provided by the manufacturer.
209. What Should the Operator Consider When Curtailing the 
Manufacturer's Loading Envelope?
    a. The operator should curtail the manufacturer's loading 
limitations to account for loading variations and in-flight movement 
that are encountered in normal operations. For example, if passengers 
are expected to move about the cabin in flight, the operator must 
curtail the manufacturer's CG envelope by an amount necessary to ensure 
that movement of passengers does not take the aircraft outside its 
certified envelope. If the aircraft is loaded within the new, curtailed 
envelope, it will always be operated within the manufacturer's 
envelope, even though some of the loading parameters, such as

[[Page 51513]]

passenger seating location, are not precisely known.
    b. In some cases an aircraft may have more than one loading 
envelope for preflight planning and loading. Each envelope must have 
the appropriate curtailments applied for those variables that are 
expected to be relevant for that envelope. For example, an aircraft 
might have separate takeoff, in-flight, and landing envelopes. 
Passengers are expected to remain seated in the cabin during take-off 
or landing. Therefore, the takeoff and landing envelope need not be 
curtailed for passenger movement.
    c. Upon determination of the curtailed version of each envelope, 
the most restrictive points (for each condition the operator's program 
will check) generated by an ``overlay'' of the envelopes will form the 
aircraft operational envelopes. These envelopes must be observed. By 
restricting operation to these ``operational envelopes,'' compliance 
with the manufacturer's certified envelope will be ensured in all 
phases of flight, based upon the assumptions within the curtailment 
process. Optionally, an operator may choose to not combine the 
envelopes but observe each envelope independently. However, due to 
calculation complexity, this is typically only possible through 
automation of the weight and balance calculation.
210. What Are Some Examples of Common Curtailments to the 
Manufacturer's Loading Envelope?
    The following subparagraphs provide examples of common loading 
curtailments. They are only examples. Operators using an approved 
weight and balance control program must include curtailments 
appropriate to the operations being conducted. Each of the items 
mentioned below is a single curtailment factor. The total curtailment 
of the manufacturer's envelope is computed by combining the 
curtailments resulting from each of these factors.
    a. Passengers. The operator must account for the seating of 
passengers in the cabin. The loading envelope need not be curtailed if 
the actual seating location of each passenger is known. If assigned 
seating is used to determine passenger location, the operator must 
implement procedures to ensure that the assignment of passenger seating 
is incorporated into the loading procedure. It is recommended that the 
operator take into account the possibility that some passengers may not 
sit in their assigned seats.
    (1) If the actual seating location of each passenger is not known, 
the operator may assume that all passengers are seated uniformly 
throughout the cabin or a specified subsection of the cabin. If this 
assumption is made, the operator must curtail the loading envelope to 
account for the fact that the passenger loading may not be uniform. The 
curtailment may make reasonable assumptions about the manner in which 
people distribute themselves throughout the cabin. For example, the 
operator may assume that window seats are occupied first, followed by 
aisle seats, followed by the remaining seats (window-aisle-remaining 
seating). Both forward and rear loading conditions should be 
considered. That is, the passengers may fill up the window, aisle, and 
remaining seats from the front of the aircraft to the back, or the back 
to the front.
    (2) If necessary, the operator may divide the passenger cabin into 
subsections or ``zones'' and manage the loading of each zone 
individually. It can be assumed that passengers will be sitting 
uniformly throughout each zone, as long as the curtailments described 
in the previous paragraph are put in place.
    (3) All such assumptions should be adequately documented.
    b. Fuel. The operator's curtailed loading envelope must account for 
the effects of fuel. The following are examples of several types of 
fuel-related curtailments:
    (1) Fuel density. A certain fuel density may be assumed and a 
curtailment included to account for the possibility of different fuel 
density values. Fuel density curtailments only pertain to differences 
in fuel moment caused by varying fuel volumes, not to differences in 
total fuel weight. The fuel gauges in most transport category aircraft 
measure weight, not volume. Therefore, the indicated weight of the fuel 
load can be assumed to be accurate.
    (2) Fuel movement. The movement or transfer of fuel in flight.
    (3) Fuel usage in flight. The burning of fuel may cause the CG of 
the fuel load to change. A curtailment may be included to ensure that 
this change does not cause the CG of the aircraft to move outside of 
the acceptable envelope.
    c. Fluids. The operator's curtailed CG envelope must account for 
the effects of galley and lavatory fluids. These factors include such 
things as:
    (1) Use of potable water in flight.
    (2) Movement of water or lavatory fluids.
    d. In-Flight Movement of Passenger and Crew. The operational 
envelope must account for the in-flight movement of passengers, crew, 
and equipment. This may be done by including a curtailment equal to the 
moment change caused by the motion being considered. It may be assumed 
that all passengers, crew, and equipment are secured when the aircraft 
is in the takeoff or landing configuration. Standard operational 
procedures may be taken into account. Examples of items that can move 
during flight are:
    (1) Flight deck crewmembers moving to the lavatory. Flight deck 
crewmembers may move to the most forward lavatory in accordance with 
the security procedures prescribed for crews leaving the cockpit. An 
offsetting credit may be taken if another crewmember moves to the 
flight deck during such lavatory trip.
    (2) Flight attendants moving throughout the cabin.
    (3) Service carts moving throughout the cabin. Operators should 
take their standard operating procedures into account. If procedures do 
not dictate otherwise, it should be assumed that the service carts can 
travel anywhere within the compartment to which they are assigned. If 
multiple carts are in a given compartment, and no restrictions are 
placed on their movement, then the maximum number of carts, moving the 
maximum distance, must be considered. The weight of the number of 
flight attendants assigned to each cart must also be considered. The 
assumed weight of each cart may be the maximum anticipated cart-load or 
the maximum design load, as appropriate to the operator's procedures.
    (4) Passengers moving throughout the cabin. Allowances should be 
made for the possibility that passengers may move about the cabin in 
flight. The most common would be movement to the lavatory, described 
below. If a lounge or other passenger gathering area is provided, the 
operator should assume that passengers move there from the centroid of 
the passenger cabin(s). The maximum capacity of the lounge should be 
taken into account.
    (5) Passengers moving to the lavatory. Operators should account for 
the CG change caused by passengers moving to the lavatory. Operators 
should develop reasonable scenarios for the movement of passengers in 
their cabins and consider the CG shifts that can be expected to occur. 
Generally, it may be assumed that passengers to move to the lavatories 
closest to their seats. In aircraft with a single lavatory, movement 
from the ``most adverse'' seat must be taken into account. Assumptions 
may be made which reflect operator lavatory and seating policies. For 
example, it may be assumed that coach passengers may only use the 
lavatories in the coach

[[Page 51514]]

cabin, if that is the operator's normal policy.
    e. Movement of Flaps and Landing Gear. If the manufacturer has not 
already done so, the operator must account for the movement of landing 
gear, flaps, wing leading edge devices, or any other moveable 
components of the aircraft. Devices deployed only while in contact with 
the ground, such as ground spoilers or thrust reversers, may be 
excluded from such curtailments.
    f. Baggage and Freight. It can be assumed that baggage and freight 
may be loaded at the centroid of each baggage compartment. Operators do 
not need to include a curtailment if procedures are used which ensure 
that the cargo is loaded uniformly throughout each compartment.

Section 4. Automated Weight and Balance Systems

211. How does an onboard weight and balance system compare to a 
conventional weight buildup method?
    a. An operator may use an onboard weight and balance system to 
calculate an aircraft's weight and balance, provided the FAA has 
approved the system for use in an operator's weight and balance control 
program. This section discusses the differences an operator should 
consider when using an onboard weight and balance system compared to a 
conventional weight buildup method. This section addresses only the 
operational considerations related to the use of an FAA-authorized 
onboard weight and balance system.
    b. Like operators using a conventional weight buildup method to 
calculate weight and balance, an operator using an onboard weight and 
balance system as a primary weight and balance control system should 
curtail the manufacturer's loading envelope to ensure the aircraft does 
not exceed the manufacturer's certificated weight and CG limits. 
However, an operator using an onboard weight and balance system would 
not need to curtail the loading envelope for assumptions about 
passenger and bag weight or distribution.
    c. Because an onboard weight and balance system measures the actual 
weight and CG location of an aircraft, an operator may not need to 
include certain curtailments to the loading envelope to account for 
variables such as passenger seating variation or variation in passenger 
weight. However, an operator should curtail the loading envelope for 
any system tolerances that may result in CG or weight errors. Using an 
onboard weight and balance system does not relieve an operator from the 
requirement to complete and maintain a load manifest.
212. What measures should an operator take to obtain operational 
approval for an onboard weight and balance system?
    a. System calibration. An operator should develop procedures to 
calibrate its onboard weight and balance system equipment periodically 
in accordance with the manufacturer's instructions. An operator may 
calibrate its system with operational items or fuel aboard the aircraft 
to test the system at a representative operational weight. However, an 
operator may not use an onboard weight and balance system in place of 
procedures described in Section 1 of this chapter for weighing the 
aircraft to establish OEW or CG location.
    b. Demonstration of system accuracy. As part of the operational 
approval process, an operator should demonstrate that its onboard 
weight and balance system maintains its certificated system accuracy 
between calibration periods. An operator should not have to conduct 
this demonstration more than once for installing a specific system on 
one type of aircraft. For the demonstration, the operator should use an 
aircraft in normal operational service, or in operations that represent 
the expected environmental and operational conditions in which the 
aircraft will operate.
213. What operational considerations should an operator take into 
account when using an onboard weight and balance system?
    a. Certification limits. An operator using an onboard weight and 
balance system as its primary means of calculating weight and balance 
should have procedures in place to ensure that the system is operated 
within the limits established during the system's certification 
process.
    b. Environmental considerations. An operator using an onboard 
weight and balance system should ensure that it uses the system within 
the environmental limits established by the manufacturer. Environmental 
conditions that may affect the performance of an onboard weight and 
balance system include temperature, barometric pressure, wind, ramp 
slope, rain, snow, ice, frost, dew, deicing fluid, etc.
    c. Aircraft considerations. An operator using an onboard weight and 
balance system should ensure the weight and CG measured by the system 
are not affected by the aircraft configuration, such as the movement of 
flaps, stabilizers, doors, stairways or jetways, or any connections to 
ground service equipment. Other factors that an operator should 
consider include engine thrust, oleo strut extension, and aircraft taxi 
movement.
    d. Takeoff trim settings. If the aircraft manufacturer provides 
trim settings for takeoff based on the aircraft's CG location, an 
operator using an onboard weight and balance system should ensure that 
the onboard weight and balance system provides flight crewmembers with 
adequate information to determine the appropriate trim setting.
    e. Operational envelope. The operational envelope for onboard 
weight and balance systems shall be developed using the same procedures 
described in other parts of this AC, with the exception that the 
operational envelope need not be curtailed for passenger random seating 
and passenger weight variance. Also note that the fuel load is 
subtracted from the measured takeoff weight to determine the zero fuel 
weight and CG, instead of being added to the zero fuel weight as part 
of the load buildup. In addition, an operator must curtail the CG 
envelope for any system CG tolerance and the weight must be curtailed 
for any system tolerance above 1 percent.
    f. Complying with compartment or unit load device (ULD) load 
limits. When using an onboard weight and balance system, an operator 
should develop in its weight and balance control program a method to 
ensure that it does not exceed the load limits specified for a 
compartment or ULD. If an operator develops appropriate procedures, an 
operator may request approval to exclude bag counts from its load 
manifest. The following are two examples of acceptable means to 
demonstrate compliance with compartment load limits.
    (1) An operator may assign a standard average weight to bags. Based 
on that standard average weight, the operator may place a placard in 
each compartment stating the maximum number of bags permitted. An 
operator may also create a table that lists the total weight associated 
with a given number of bags to ensure the operator does not exceed the 
load limit of a compartment or ULD.
    (2) By conducting sample loadings, an operator may demonstrate that 
the average density of the bags it places in a compartment or ULD would 
not allow it to exceed the compartment or ULD load limits 
inadvertently.

[[Page 51515]]

214. May an operator use the information in this AC to develop a backup 
system?
    An operator using an onboard weight and balance system as its 
primary means of calculating weight and balance may use the guidance in 
this AC to develop a backup system based on a conventional weight 
buildup. If an operator develops and receives approval for a backup 
system, the FAA may grant the operator relief to include an onboard 
weight and balance system in the operator's minimum equipment list.
215. What operational considerations should an operator take into 
account when using a computerized weight and balance system?
    a. An operator may use an installed computerized weight and balance 
system to calculate the load schedule for the aircraft's weight and 
balance for primary dispatch, provided that the system received 
certification and operational approval for use in an operator's 
approved weight and balance control program. The system consists of a 
computer program that runs on installed Electronic Flight Bag computing 
devices or the Aircraft Communication Addressing and Reporting System, 
and can be downloaded to ground operations via electronic links. The 
system displays the load sheet to the pilot or flight operations for 
primary dispatch.
    b. Like operators using a conventional weight buildup method to 
calculate weight and balance, an operator may use the computerized 
weight and balance system to provide the FAA approved loading 
schedules. The operator who uses the computerized weight and balance 
system as part of its approved weight and balance program should meet 
all provisions pertinent to the operator's approved weight and balance 
program as described in this AC.

Chapter 3. Methods to Determine the Weight of Passengers and Bags

Section 1. Choosing the Appropriate Method

300. What should an operator consider when choosing the appropriate 
method?
    a. For many years, operators of transport category aircraft have 
used average weights for passengers and bags to calculate an aircraft's 
weight and balance, in accordance with standards and recommended 
practices. This method eliminates many potential sources of error 
associated with accounting for a large number of relatively light 
weights. However, differences between the actual weight of passengers 
and bags and the average weight of passengers and bags can occur when 
using average weights.
    b. Statistical probability dictates that the smaller the sample 
size (i.e., cabin size), the more the average of the sample will 
deviate from the average of the larger universe. Because of this, the 
use of standard average passenger weights in weight and balance 
programs for small and medium cabin aircraft should be examined in 
greater detail.
    c. The next four sections describe four methods available to 
operators to determine passenger and bag weight. They are standard 
average weights in Section 2; average weights based on survey results 
in Section 3; segmented weights in Section 4; and actual weights in 
Section 5. An operator should review the following discussion and 
consult Table 3-1 to determine which method or methods are appropriate 
to its type of operation.
    d. Large Cabin Aircraft. Operators of large cabin aircraft may use 
the standard average weights for passengers and bags. If an operator 
determines that the standard average weights are not representative of 
its operation for some route or regions, it is encouraged to conduct a 
survey as detailed in Section 3 of this chapter, to establish more 
appropriate average weights for its operation. Operators should have 
procedures for identifying situations that would require the use of 
nonstandard or actual weights.
    e. Medium Cabin Aircraft. Medium cabin aircraft should be evaluated 
to determine if the aircraft should be treated more like large or small 
cabin aircraft. To determine if a medium cabin aircraft can be treated 
as a large cabin aircraft, the aircraft must meet either both of the 
loadability criteria or the loading schedule criteria or else be 
subject to the small cabin weights and curtailments:
    Loadability Criteria:
     The CG of the OEW is within the manufacturer's loading 
envelope, and
     The CG of the zero fuel weight is within the 
manufacturer's loading envelope when loaded with a full load of 
passengers and all cargo compartments are filled with a density of 10 
pounds per cubic foot.

Or
    Loading Schedule Criteria:
     The operator must use a loading schedule based upon zones. 
The aircraft cabin may have no more than four rows per zone with not 
less than four zones.
    f. Small Cabin Aircraft. Operators of small cabin aircraft may 
request approval to use any one of the following methods when 
calculating the aircraft weight and balance.
    (1) The operator may use actual passenger and bag weights, or
    (2) The operator may use the segmented passenger weights listed in 
Table 3-5 and average bag weights listed in Section 2 of this chapter, 
or
    (3) The operator may use the standard average passenger and bag 
weights prescribed for large cabin aircraft, or average weights based 
on an FAA-accepted survey, if--
    (a) The aircraft was certificated under part 23 commuter category, 
part 25, or part 29 (or is able to prove an aircraft has equivalent 
part 25 or 29 performance data), and
    (b) The operator curtails the aircraft CG envelope as prescribed in 
Appendixes 3 and 4 of this AC.

Section 2. Standard Average Weights

301. What standard average passenger weights should an operator with an 
approved carry-on bag program use?
    a. The standard average passenger weights provided in Table 3-1 
were established based on data from U.S. Government health agency 
surveys. For more background information on the source of these 
weights, refer to Appendix 2.
    b. The standard average passenger weights in Table 3-1 include 5 
pounds for summer clothing, 10 pounds for winter clothing, and a 16-
pound allowance for personal items and carry-on bags. Where no gender 
is given, the standard average passenger weights are based on the 
assumption that 50 percent of passengers are male and 50 percent of 
passengers are female.

[[Page 51516]]

[GRAPHIC] [TIFF OMITTED] TN19AU04.002

    c. An operator may use summer weights from May 1 to October 31 and 
winter weights from November 1 to April 30. However, these dates may 
not be appropriate for all routes or operators. For routes with no 
seasonal variation, an operator may use the average weights appropriate 
to the climate. Use of year-round average weights for operators with 
seasonal variation should avoid using an average weight that falls 
between the summer and winter average weights. Operators with seasonal 
variation that elect to use a year-round average weight should use the 
winter average weight. Use of seasonal dates, other than those listed 
above, will be entered as nonstandard text and approved through the 
operator's OpSpec, MSpec, or LOA, as applicable.
    d. The standard average weights listed in Table 3-1 are based on 
the assumption that the operator has a carry-on bag program. Operators 
using a no-carry-on bag program should refer to paragraph 305 of this 
section.

    Note: The weight of children under the age of 2 has been 
factored into the standard average and segmented adult passenger 
weights.

302. What standard average weights should an operator use for carry-on 
bags and personal items?
    a. An operator using standard average passenger weights should 
include the weight of carry-on bags and personal items in the 
passenger's weight. The standard average passenger weights in Table 3-1 
include a 16-pound allowance for personal items and carry-on bags, 
based on the assumption that--
    (1) One-third of passengers carry one personal item and one carry-
on bag.
    (2) One-third of passengers carry one personal item or carry-on 
bag.
    (3) One-third of passengers carry neither a personal item nor a 
carry-on bag.
    (4) The average weight allowance of a personal item or a carry-on 
bag is 16 pounds.
    b. If an operator believes the 16-pound allowance for personal 
items and carry-on bags is not appropriate for its operations or 
receives notification from the FAA that the assumptions provided in 
paragraph 302a are not consistent with the operator's approved program, 
the operator should conduct a survey to determine what percentage of 
passengers carry personal items or carry-on bags aboard the aircraft. 
An example of how to adjust the personal item and carry-on bag 
allowance, based on the results of a survey, is in Section 3. An 
operator should not use an allowance of less than 16 pounds for 
personal items and carry-on bags unless the operator conducts a survey 
or unless the operator has a no-carry-on bag program.
303. What standard average weights should an operator use for checked 
bags?
    An operator that chooses to use standard average weights for 
checked bags should use a standard average weight of at least 30 
pounds. An operator that requests approval to use a standard average 
weight of less than 30 pounds for checked bags should have current, 
valid survey data to support a lesser weight. An operator also may 
conduct a study to establish different standard average bag weights for 
portions of its operation to account for regional, seasonal, 
demographic, aircraft, or route variation. For example, an operator 
could establish different standard average bag weights for domestic and 
international routes.
    a. Heavy bags. Heavy bags are considered any bag that weighs more 
than 50 pounds but less than 100 pounds. An operator should account for 
a heavy bag by using one of the following weights:
    (1) A standard average weight of 60 pounds,
    (2) An average weight based on the results of a survey of heavy 
bags, or
    (3) The actual weight of the heavy bag.

    Note: An operator that uses ``double-counting'' to treat a heavy 
bag as if it were two checked bags for weight purposes should ensure 
the load manifest represents the actual number of bags for counting 
purposes. An operator should have a system in place to ensure that 
heavy bags are identified, although operators may not be required to 
weigh heavy bags on a scale.
    b. Non-luggage bags. A non-luggage bag is any bag that does not 
meet the normal criteria for luggage. Examples include golf bags, 
fishing equipment packages, wheelchairs and strollers in their 
shipping configuration, windsurfing kits, boxed bicycles, etc. For 
non-luggage bags, operators may use any appropriate combination of 
actual weights, average weights based on survey results, or standard 
average bag weights. Operators that wish to establish an average 
weight for a particular type of non-luggage bag, such as a golf bag, 
must conduct a survey in accordance with the procedures established 
in Section 3 of this chapter. Operators also should establish a 
method to calculate the effect on CG of a large non-luggage bag, 
such as a surfboard, that may occupy more than one compartment on 
the aircraft.


[[Page 51517]]


304. What standard average weight should an operator of large cabin 
aircraft use for bags checked plane-side?
    Operators with a carry-on bag program that use standard average 
weights should account for the weight of each carry-on bag checked 
plane-side as 30 pounds. An operator may request approval to use a 
weight other than 30 pounds if the operator has current, valid survey 
data to support a different average weight for plane-side-loaded bags.
305. What standard average weights should an operator of small and 
medium cabin aircraft use, if it has a ``no-carry-on bag program?'

    Note: A no-carry-on bag program is limited to small and medium 
cabin aircraft. A no-carry-on bag program is a term of art created 
for this AC. Associated with this program are certain standard 
average weight credits and reductions. Nothing in this AC prevents 
an operator of large cabin aircraft from having a no-carry-on bag 
``policy;'' however, the acceptable standard bag weights for such 
checked baggage for large cabin aircraft are outlined in paragraphs 
303 and 304 above. Furthermore, the passenger weight credit 
associated with a no-carry-on-bag program is limited to the small 
and medium cabin aircraft.

    a. An operator with a no-carry-on bag program may allow passengers 
to carry only personal items aboard the aircraft. Because these 
passengers do not have carry-on bags, an operator may use standard 
average passenger weights that are 6 pounds lighter than those for an 
operator with an approved carry-on bag program. See Table 3-2.
[GRAPHIC] [TIFF OMITTED] TN19AU04.003

    b. An operator that has a no-carry-on bag program may account for a 
plane-side loaded bag as 20 pounds. To receive authorization to use 20 
pounds as the average weight for a plane-side loaded bag, an operator 
should demonstrate that sufficient controls exist to ensure that 
passengers do not bring carry-on bags aboard the aircraft. An operator 
also should demonstrate that sufficient controls exist to ensure the 
personal items brought aboard the aircraft can fit completely under a 
passenger seat or in an approved stowage compartment.
    c. If an operator discovers that a plane-side loaded bag should 
have been treated as a checked bag, the operator should account for 
that bag at the standard average weight of 30 pounds for a checked bag.
306. What are the standard average weights for crewmembers?
    a. An operator may choose to use the standard crewmember weights 
shown in Table 3-3 or conduct a survey to establish average crewmember 
weights appropriate for its operation.
[GRAPHIC] [TIFF OMITTED] TN19AU04.028


[[Page 51518]]


    b. The flight crewmember weights in Table 3-3 were derived from 
weights listed on all first- and second-class medical certificates. The 
flight crewmember weight with bags assumes that each flight crewmember 
has one crewmember roller bag and one pilot flight bag.
    c. The flight attendant weights in Table 3-3 were derived from 
National Health and Nutrition Examination Survey (NHANES) data. (For 
additional information on NHANES, see Appendix 2.) The flight attendant 
weights with bags assume that each flight attendant has one crewmember 
roller bag and one flight attendant kit.
    d. An operator may include the weight of crewmembers in an 
aircraft's OEW or add the weight to the load manifest prepared for each 
flight.
307. What weights may be used for company materials and mail?
    a. Company Material. An operator should use actual weights for 
company material and aircraft parts carried aboard an aircraft.
    b. Mail. An operator should use the weights provided with 
manifested mail shipments to account for the weight of the mail. If an 
operator has to separate a shipment of mail, the operator may make 
actual estimates about the weight of the individual pieces, provided 
the sum of the estimated weights is equal to the actual manifested 
weight of the entire shipment.
308. What are the standard average weights for special passenger groups 
that do not fit an operator's standard average weight profile?
    a. Sports Teams.
    (1) Actual passenger weights should be used for nonstandard weight 
groups (sports teams, etc.) unless average weights have been 
established for such groups by conducting a survey in accordance with 
the procedures established in Section 3 of this chapter. When such 
groups form only a part of the total passenger load, actual weights, or 
established average weights for the nonstandard group, may be used for 
such exception groups and average weights used for the balance of the 
passenger load. In such instances, a notation should be made in the 
load manifest indicating the number of persons in the special group and 
identifying the group; e.g., football squad, etc.
    (2) Roster weights may be used for determining the actual passenger 
weight.
    (3) A standard allowance of 16 pounds per person may be used to 
account for carry-on and personal items as provided in the operator's 
approved carry-on bag program.
    (4) If the carry-on bags are representative of the operator's 
profile but do not meet the number of bags authorized per person, the 
operator may count bags and use a 16 pounds per bag allocation.
    (5) Actual weights must be used in cases where the carry-on bags 
are not representative of the operator's profile.
    b. Groups that are predominantly male or female should use the 
standard average weights for males or females provided in Table 3-1.
    c. Military Groups. The Department of Defense (DOD) requires actual 
passenger and cargo weights be used in computing the aircraft weight 
and balance for all DOD charter missions. This requirement is specified 
in DOD Commercial Air Carrier Quality and Safety requirements 
(reference 32 CFR part 861, section 861.4(e)(3)(ix), as revised). FAA-
approved air carrier weight and balance control programs may be used to 
account for carry-on/personal items for mixed loads of military and 
their dependents (such as channel missions). For combat-equipped troop 
charters, the Air Mobility Command (AMC) will provide guidance to 
account for the additional weight. If aircraft operators perceive that 
the weights provided are understated, they should seek confirmation of 
the actual weights and should make reasonable upward estimations and 
adjustments to those passenger and/or bag weights.

Section 3. Average Weights Based on Survey Results

309. What should an operator consider when designing a survey?
    a. This section provides operators with an acceptable survey method 
to use in determining average weights for a weight and balance control 
program. This section also describes how an operator can conduct a 
survey to count personal items and carry-on bags to determine an 
appropriate allowance for those items to include in passenger weight. 
In addition, an operator may use the methods described in this section 
to conduct a survey to determine the percentage of male and female 
passengers, to calculate an average passenger weight.
    b. Surveys conducted correctly allow an operator to draw reliable 
inferences about large populations based on relatively small sample 
sizes. In designing a survey, an operator should consider--
    (1) The sample size required to achieve the desired reliability,
    (2) The sample selection process, and
    (3) The type of survey (average weights or a count of items).
310. What sample sizes should an operator use?
    Several factors must be considered when determining an adequate 
sample size. The more varied the population, the larger the sample size 
required to obtain a reliable estimate. Paragraph 311 provides a 
formula to derive the absolute minimum sample size to achieve a 95-
percent confidence level. Table 3-4 has been provided for those 
operators that wish to use calculations other than those listed in 
paragraph 311. Table 3-4 provides the operator with an acceptable 
number of samples that may be collected to obtain a 95-percent 
confidence level and lists the tolerable error associated with each 
category.

[[Page 51519]]

[GRAPHIC] [TIFF OMITTED] TN19AU04.004

311. When conducting a survey, can an operator collect a smaller sample 
size than that published in Table 3-4?
    If the operator has chosen to use a sample size that is smaller 
than that provided in Table 3-4, the operator should collect a 
sufficient number of samples to satisfy the following formulas:
[GRAPHIC] [TIFF OMITTED] TN19AU04.005

Where:
s is the standard deviation
n is the number of points surveyed
xj is the individual survey weights
x is the sample average
[GRAPHIC] [TIFF OMITTED] TN19AU04.006

Where:
e is the tolerable error
312. What sampling method should an operator use?
    a. An operator conducting a survey must employ random sampling 
techniques. Random sampling means that every member of a group has an 
equal chance of being selected for inclusion in the sample. If an 
operator conducts a survey that does not employ random sampling, the 
characteristics of the selected sample may not be indicative of the 
larger group as a whole. Because of this, any conclusions drawn from 
such a survey may not be valid.
    b. The following are two examples of random sampling methods that 
an operator may find appropriate for the type of survey conducted. An 
operator may also consult a basic textbook on statistics to determine 
if another random sampling method is more appropriate.
    (1) Simple random selection. An operator should assign a sequential 
number to each item in a group (such as passengers waiting on a line or 
bag claim tickets). Then the operator randomly selects numbers and 
includes the item corresponding with the number in the sample. The 
operator repeats this process until it has obtained the minimum sample 
size.
    (2) Systematic random selection. An operator should randomly select 
an item in sequence to begin the process of obtaining samples. The 
operator should then use a predetermined, systematic process to select 
the remaining samples following the first sample. For example, an 
operator selects the third person in line to participate in the survey. 
The operator then selects every fifth person after that to participate 
in the survey. The operator continues selecting items to include in the 
sample until it has obtained the minimum sample size.
    c. Regardless of the sampling method used, an operator has the 
option of surveying each passenger and bag aboard the aircraft and 
should always give a passenger the right to decline to participate in 
any passenger or bag weight survey. If a passenger declines to 
participate, the operator should select the next passenger based on the 
operator's random selection method rather than select the next 
passenger in a line. If a passenger declines to participate, an 
operator should not attempt to estimate data for inclusion in the 
survey.
313. What should an operator consider when developing a survey plan and 
submitting it to the FAA?
    a. Developing a survey plan. Before conducting a survey, an 
operator should develop a survey plan. The plan should describe the 
dates, times, and locations the survey will take place. In developing a 
survey plan, the operator should consider its type of operation, hours 
of operation, markets served, and frequency of flights on particular 
routes. An operator should avoid conducting surveys on holidays unless 
it has a valid reason to request the particular date.
    b. Submitting the survey plan to the FAA. It is recommended that an 
operator submit its survey plan to the FAA at least 2 weeks before the 
survey is expected to begin. Before the survey begins, the operator's 
principal inspectors (PI) will review the plan and work with the 
operator to develop a mutually acceptable plan. During the survey, the 
PI will oversee the survey process to validate the execution of the 
survey plan. After the survey is complete, the PI will review the 
survey results and issue the appropriate OpSpecs or MSpecs. Once a 
survey begins, the operator should continue the survey until complete, 
even if the initial survey data indicates that the average weights are 
lighter or heavier than expected.
314. What general survey procedures should an operator use?
    a. Survey locations. An operator should accomplish a survey at one 
or more airports that represent at least 15 percent of an operator's 
daily departures. To provide connecting passengers with an equal chance 
of being selected in the survey, an operator should conduct its survey 
within the secure area of the airport. An operator should select 
locations to conduct its survey that would provide a sample that is 
random and representative of its operations. For example, an operator 
should not conduct a survey at a gate used by shuttle operations unless 
the operator is conducting a survey specific to that route or the 
operator only conducts shuttle operations.
    b. Weighing passengers. An operator that chooses to weigh 
passengers as part of a survey should take care to protect the privacy 
of passengers. The scale

[[Page 51520]]

readout should remain hidden from public view. An operator should 
ensure that any passenger weight data collected remains confidential.
    c. Weighing bags. When weighing bags on a particular flight, an 
operator should take care to ensure that it is properly accounting for 
all items taken aboard the aircraft.
    d. Rounding sample results. If the operator uses rounding in the 
weight and balance calculations, it is recommended that the operator 
round passenger weights to the nearest pound and bag weights to the 
nearest half-pound. An operator should ensure that rounding is done 
consistently in all calculations.
    e. Surveys for particular routes. An operator may conduct a survey 
for a particular route if the operator believes that the average 
weights on that route may differ from those in the rest of its 
operations. To establish a standard average passenger weight along the 
route, an operator may survey passengers at only one location. However, 
an operator should conduct surveys of personal items and bags at the 
departure and arrival locations, unless the operator can verify there 
is no significant difference in the weight and number of bags in either 
direction along the route.
315. What information might an operator gain from conducting a count 
survey?
    a. An operator may conduct a survey to count certain items without 
determining the weight of those items. For example, an operator may 
determine that the standard average weights for male and female 
passengers are appropriate for its operations, but on some routes the 
passengers are predominantly male or female. In this case, an operator 
may conduct a survey to determine the percentage of male and female 
passengers. The operator could use the results of the survey to justify 
a weight other than the standard weights, which assume a 50-percent 
male and 50-percent female mix of passengers. Similarly, an operator 
may conduct a survey to determine the number of personal items and 
carry-on bags passengers carry aboard aircraft to determine if the 
allowance of 16 pounds per passenger is appropriate to its operations.
    b. For example, an operator conducts a survey on a particular route 
(or multiple routes if amending the program average weight) to count 
the percentage of passengers carrying personal items and carry-on bags. 
The operator finds that--
    (1) Fifty percent of passengers carry one carry-on bag and one 
personal item.
    (2) Thirty percent of passengers carry one carry-on bag or one 
personal item.
    (3) Twenty percent of passengers carry neither a carry-on bag nor a 
personal item.
    (4) The survey results show that the average passenger carries 
approximately 21 pounds of personal items and carry-on bags rather than 
the standard allowance of 16 pounds. In such a case, it would be 
irresponsible for the operator to fail to increase the standard average 
weights for that route(s) by 5 pounds per passenger.

    Note: The calculation below determines the appropriate allowance 
for personal items and carry-on bags.


0.50 `` (16 pounds + 16 pounds)] + [0.30 `` (16 pounds)] + [0.20 ``(0 
pounds)] = 20.8 pounds
316. When should an operator conduct another survey to revalidate the 
data from an earlier survey?
    In order to use survey-derived average weights, an operator must 
revalidate such survey data every 36 calendar-months or revert to the 
standard average weights, provided the new survey average weight 
results are within 2 percent of the standard average weights listed in 
this AC.

Section 4. Segmented Passenger Weights

317. What should an operator consider when using segmented weights?
    a. The concept of segmented weights involves adding a portion of 
the standard deviation to an average weight to increase the confidence 
that the actual weight will not exceed the average weight. Like the 
standard average weights in Section 2, the segmented weights in Table 
3-5 were derived from average weights and standard deviations found 
based on NHANES data, assuming a 95-percent confidence interval and 1-
percent tolerable error.
[GRAPHIC] [TIFF OMITTED] TN19AU04.007


[[Page 51521]]


    b. An operator may make the following adjustments to the table 
above:
    (1) An operator may subtract 6 pounds from the passenger weight 
outlined above if it has a no-carry-on bag program or does not allow 
any carry-on baggage into the cabin of the aircraft.
    (2) An operator should add 5 pounds to the weights above during the 
winter season.
    c. An operator may interpolate between columns on the chart if the 
operator's assumed ratio of male passengers to female passengers does 
not exactly match the values given.
    d. To account for a child's weight, for children ages 2 years to 
less than 13 years of age, the standard average child weight located in 
Table 3-1 may be used. Weights of children under the age of 2 have been 
factored into the segmented adult passenger weight.
318. How are loading envelope curtailment and bag weight affected by an 
operator's use of segmented weights?
    a. Loading envelope curtailment. An operator using segmented 
passenger weights should consider curtailing its operational loading 
envelope using the methods described in Appendix 4.
    b. Bag weights. An operator using segmented weights may use actual 
weights for bags or the standard average bag weights provided in 
Section 2. An operator using segmented passenger weights may not use 
survey-derived average bag weights.
319. What might be an example of an operator using the segmented 
weights in Table 3-5?
    An operator of a 30 passenger-seat aircraft conducts a survey to 
count the percentage of male and female passengers on its flights and 
determines that 50 percent of its passengers are male and 50 percent 
are female. If the operator has an approved carry-on bag program, the 
operator should use 204 pounds in the summer and 209 pounds in the 
winter. If the operator has a no-carry-on bag program, the operator 
should use 198 pounds in the summer and 203 pounds in the winter and 
account for all plane-side loaded bags as 20 pounds each.

Section 5. Actual Weight Programs

320. If the operator decides to use an actual weights program, how 
might it determine the actual weight of passengers?
    An operator may determine the actual weight of passengers by--
    a. Weighing each passenger on a scale before boarding the aircraft 
(types of weight scales and scale tolerances will be defined in the 
operator's approved weight and balance control program); or
    b. Asking each passenger his or her weight. An operator should add 
to this asked (volunteered) weight at least 10 pounds to account for 
clothing. An operator may increase this allowance for clothing on 
certain routes or during certain seasons, if appropriate.

    Note: If an operator believes that the weight volunteered by a 
passenger is understated, the operator should make a reasonable 
estimate of the passenger's actual weight and add 10 pounds.

321. If the operator decides to use an actual weight program, how 
should it determine the actual weights of personal items and bags?
    To determine the actual weight of a personal item, carry-on bag, 
checked bag, plane-side loaded bag, or a heavy bag, an operator should 
weigh the item on a scale.
322. What approach should an operator use to record actual weights?
    An operator using actual weights should record all weights used in 
the load buildup.

Chapter 4. Operator Reporting Systems and FAA Oversight

Section 1. Pilot and Agent Reporting Systems

400. What are the pilots' and operators' responsibilities in reporting 
aircraft loading and manifest preparation discrepancies?
    Each operator should develop a reporting system and encourage 
employees to report any discrepancies in aircraft loading or manifest 
preparation. These discrepancies may include errors in documentation or 
calculation, or issues with aircraft performance and handling qualities 
that indicate the aircraft weight or balance is not accurate. Operators 
should attempt to determine the cause of each discrepancy and take 
appropriate corrective action. This would include a load audit on 
affected flights or conducting a passenger or bag weight survey in 
accordance with this AC if trends indicate it is warranted.

Section 2. FAA Oversight

401. Which FAA inspectors are responsible for overseeing an operator's 
weight and balance program?
    The FAA has divided the responsibility of overseeing an operator's 
weight and balance control program between the operator's principal 
operations inspector (POI) and principal maintenance inspector (PMI). 
An operator that wishes to change aspects of its weight and balance 
control program, including average weights, should submit all 
applicable supporting data to the POI and PMI, as applicable, for 
approval. If the FAA approves the changes, the FAA will issue revised 
OpSpecs, MSpecs, or LOA, as appropriate.
402. Which portions of OpSpecs or MSpecs are relevant to an operator's 
weight and balance program?
    a. This AC details methods to develop a weight and balance control 
program with greater accuracy and increased flexibility. By changing 
its OpSpecs or MSpecs, an operator may alter the weights used in its 
weight and balance control program to include appropriate combinations 
of standard average weights, average weights based on survey results, 
or actual weights.
    b. Parts A and E of OpSpecs or MSpecs authorize an operator's 
weight and balance control program. These parts will address--
    (1) Average passenger and bag weights;
    (2) Situations when the use of average weights is inappropriate;
    (3) The treatment of charter flights or special groups, if 
applicable;
    (4) The type of loading schedule and instructions for its use;
    (5) Aircraft weighing schedules; and
    (6) Other procedures that the operator may require to assure 
control of weight and balance.
    c. Paragraph E096 of the OpSpecs or MSpecs is issued to an operator 
with an approved aircraft fleet actual or average weight program. The 
FAA issues this paragraph after reviewing and approving an operator's 
weight and balance control program in its entirety.
    d. Paragraph A011 of the OpSpecs or MSpecs is issued to an operator 
with an approved carry-on bag program. This paragraph provides details 
about the operator's approved carry-on bag program and states whether 
the operator has a carry-on bag program or a no-carry-on bag program. 
The FAA will issue this paragraph after reviewing the operator's carry-
on baggage program in its entirety.
    e. If an operator chooses to use standard average weights as 
outlined in this AC, the FAA will document that decision by issuing one 
or more of the following OpSpecs or MSpecs paragraphs. If an operator 
proposes to use different average weights (weights other than the 
standard average or segmented weights) and the FAA concurs with the 
statistically valid data provided by the operator to support

[[Page 51522]]

such average weight differences, then those differences will be 
documented in the following OpSpecs or MSpecs. Although these 
paragraphs authorize an operator to use average and/or segmented 
weights, an operator may use actual weights at any time once issued 
these paragraphs.
    (1) Paragraph A097--Small Cabin Aircraft Passenger and Baggage 
Weight Program.
    (2) Paragraph A098--Medium Cabin Aircraft Passenger and Baggage 
Weight Program.
    (3) Paragraph A099--Large Cabin Aircraft Passenger and Baggage 
Weight Program.

    Note: If an operator does not provide the FAA with adequate 
information to justify the issuance of one of the above paragraphs 
that documents the use of standard average, survey-derived average, 
and/or segmented weights, the FAA may issue paragraph A096, 
requiring the operator to use actual weights for a specific aircraft 
or aircraft fleet.


    f. If an operator chooses to develop a weight and balance control 
program using only actual weights for all the aircraft it operates, the 
FAA may issue OpSpec/MSpec paragraph A096. The FAA will not issue 
paragraphs A097, A098, or A099 to operators with a weight and balance 
control program that uses only actual weights. The FAA will only issue 
paragraphs A096, A097, A098, and/or A099 after reviewing the operator's 
actual or average weight program.
    g. An operator that receives approval to use nonstandard average 
weights should document and make available, upon request, the data and 
methodology used to derive those weights. An operator's documentation 
should be sufficiently comprehensive to allow the FAA to reproduce the 
same results during an audit. An operator should retain this 
documentation for as long as the operator uses the nonstandard average 
weights in its weight and balance control program.
    h. If an operator chooses to conduct a survey, the operator will 
use the results of the survey to establish a revised average weight and 
must curtail the loading envelope as necessary. However, if the survey 
results indicate the average weights are within 2 percent of the 
standard average weights outlined in this AC, the operator may elect to 
adopt the standard average weights only after submitting the survey 
results to the FAA and receiving approval through its OpSpecs, MSpecs, 
or LOA.
    i. For operators using an onboard weight and balance system to 
determine the weight and balance of the aircraft, the FAA will issue 
OpSpecs or MSpecs paragraph A096. Paragraph A096 documents the use of 
actual weights and the use of its onboard weight and balance system. 
For an operator that chooses to use standard average weights as a 
backup system, the FAA will issue paragraphs A097, A098, or A099, as 
appropriate. By authorizing the use of average weights, the operator 
may elect to use actual weights derived from its onboard weight and 
balance system, and may use average weights as an alternative should 
the system be inoperative.
    j. For operators of all-cargo aircraft, the FAA will issue OpSpecs 
or MSpecs paragraph A096. Paragraph A096 documents the use of actual 
weights, with the exception of flightcrew and flightcrew bag weights. 
These weights may be accounted for using the standard average weights 
described in Chapter 3, Table 3-3.
403. When will the FAA revise the standard average weights in this AC?
    The FAA will periodically review the standard average passenger 
weights listed in this AC, after the release of a new NHANES. If the 
FAA finds that the data from NHANES indicates a weight change of more 
than 2 percent, the FAA will revise this AC to update the standard 
average weights.

James J. Ballough,
Director, Flight Standards Service.

Appendix 1. Definitions

    1. Basic empty weight. The aircraft empty weight, adjusted for 
variations in standard items.
    2. Cargo. As used in this advisory circular (AC), cargo refers 
to everything carried in the cargo compartments of the aircraft. 
This includes bags, mail, freight, express, and company material. It 
also includes live animals, dangerous goods, and hazardous materials 
as subcategories of the above.
    3. Carry-on bag. A bag that the operator allows the passenger to 
carry onboard. It should be of a size and shape that will allow it 
to be stowed under the passenger seat or in a storage compartment. 
The operator establishes the exact dimensional limits based on the 
particular aircraft stowage limits.
    4. Certificated weight and CG limits. Weight and center of 
gravity (CG) limits are established at the time of aircraft 
certification. They are specified in the applicable aircraft flight 
manual (AFM).
    5. Checked bags. Checked bags are those bags placed in the cargo 
compartment of the aircraft. This includes bags that are too large 
to be placed in the cabin of the aircraft or those bags that are 
required to be carried in the cargo compartment by regulation, 
security program, or company policy. For bags checked plane-side, 
see the definition for plane-side loaded bags.
    6. Curtailment. Creating an operational loading envelope that is 
more restrictive than the manufacturers' CG envelope, to assure the 
aircraft will be operated within limits during all phases of flight. 
Curtailment typically accounts for, but is not limited to, in-flight 
movement, gear and flap movement, cargo variation, fuel density, 
fuel burn-off, and seating variation.
    7. Fleet empty weight. Average operational empty weight (OEW) 
used for a fleet or group of aircraft of the same model and 
configuration.
    8. Freight. Cargo carried for hire in the cargo compartment that 
is not mail or passenger bags.
    9. Heavy bags. For this AC, heavy bags are considered any bag 
that weighs more than 50 pounds but less than 100 pounds. Bags that 
are 100 pounds or more are considered freight.
    10. Large cabin aircraft. Aircraft with a maximum type-
certificated seating capacity of 71 or more passenger seats.
    11. Loading envelope. Weight and CG envelope used in a loading 
schedule. Loading the aircraft within the loading envelope will 
maintain the aircraft weight and CG within the manufacturer's type-
certificated limits throughout the flight.
    12. Loading schedule. Method for calculating and documenting 
aircraft weight and balance prior to taxiing, to ensure the aircraft 
will remain within all required weight and balance limitations 
throughout the flight.
    13. Manufacturer's empty weight. Weight of structure, 
powerplant, furnishings, systems, and other items of equipment that 
are an integral part of a particular aircraft configuration. (It is 
essentially a ``dry'' weight, including only those fluids contained 
in closed systems.)
    14. Maximum landing weight. The maximum weight at which the 
aircraft may normally be landed.
    15. Maximum takeoff weight. The maximum allowable aircraft 
weight at the start of the takeoff run.
    16. Maximum taxi weight. The maximum allowable aircraft weight 
for taxiing.
    17. Maximum zero-fuel weight. The maximum permissible weight of 
an aircraft with no disposable fuel and oil.
    18. Medium cabin aircraft. Aircraft with a maximum type-
certificated seating capacity between 70 and 30 passenger seats, 
inclusive.
    19. Moment. A force that causes or tries to cause an object to 
rotate.
    20. Onboard weight and balance system. A system that weighs an 
aircraft and payload, then computes the CG using equipment onboard 
the aircraft.
    21. Operational empty weight (OEW). Basic empty weight or fleet 
empty weight plus operational items.
    22. Operational items. Personnel, equipment, and supplies 
necessary for a particular operation but not included in basic empty 
weight. These items may vary for a particular aircraft and may 
include, but are not limited to, the following:
    a. Crewmembers, supernumeraries, and bags;
    b. Manuals and navigation equipment;
    c. Passenger service equipment, including pillows, blankets, and 
magazines;
    d. Removable service equipment for cabin, galley, and bar;

[[Page 51523]]

    e. Food and beverage, including liquor;
    f. Usable fluids, other than those in useful load;
    g. Required emergency equipment for all flights;
    h. Life rafts, life vests, and emergency transmitters;
    i. Aircraft unit load devices;
    j. Potable water;
    k. Drainable unusable fuel;
    l. Spare parts normally carried aboard and not accounted for as 
cargo; and
    m. All other equipment considered standard by the operator.
    23. Passenger assist/comfort animals and devices. These include, 
but are not limited to, canes, crutches, walkers, wheelchairs, 
medically-required animal comfort companions, or animals required to 
assist the vision impaired.
    24. Passenger weight. Passenger weight is the actual weight or 
the approved average weight of the passenger.
    a. An adult is defined as an individual 13 years or older.
    b. A child is defined as an individual aged 2 to less than 13 
years of age.
    c. Infants are children who have not yet reached their second 
birthday and are considered part of the adult standard average and 
segmented passenger weight.
    25. Personal item. Items the operator may allow a passenger to 
carry aboard, in addition to a carry-on bag. Typically, an operator 
may allow one personal item such as a purse, briefcase, computer and 
case, camera and case, diaper bag, or an item of similar size. Other 
items, such as coats, umbrellas, reading material, food for 
immediate consumption, infant restraining device, and passenger 
assist/comfort animals and devices, are allowed to be carried on the 
aircraft and are not counted against the personal item allowance.
    26. Plane-side loaded bag. Any bag or item that is placed at the 
door or steps of an aircraft and subsequently placed in the aircraft 
cargo compartment or cargo bin.
    27. Reference Balance Arm (BA). The horizontal distance from the 
reference datum to the CG of an item.
    28. Segmented Weights. Passenger weights derived by adding a 
portion of the standard deviation to an average weight to increase 
the confidence that the actual weight will not exceed the average 
weight.
    29. Small cabin aircraft. Aircraft with a maximum type-
certificated seating capacity between 5 and 29 passenger seats, 
inclusive.
    30. Standard basic empty weight. Manufacturer's empty weight 
plus standard items.
    31. Standard items. Equipment and fluids not considered an 
integral part of a particular aircraft and not a variation for the 
same type of aircraft. These items may include, but are not limited 
to, the following:
    a. Unusable fuel and other unusable fluids;
    b. Engine oil;
    c. Toilet fluid and chemical;
    d. Fire extinguishers, pyrotechnics, and emergency oxygen 
equipment;
    e. Structure in galley, buffet, and bar; and
    f. Supplementary electronic equipment.
    32. Useful Load. Difference between takeoff weight and OEW. It 
includes payload, usable fuel, and other usable fluids not included 
as operational items.

Appendix 2. Source of Standard Average Weights in This AC

    1. Standard average passenger weights.
    a. The Federal Aviation Administration (FAA) examined data from 
several large-scale, national health studies conducted by U.S. 
Government health agencies. The FAA found that the National Health 
and Nutrition Examination Survey (NHANES), conducted by the Centers 
for Disease Control (CDC), provided the most comprehensive and 
appropriate data. The data in NHANES cover a broad spectrum of the 
general population, are based on a large sample size, and are not 
restricted geographically to a particular area.
    b. The CDC collects NHANES data annually by conducting an actual 
scale weighing of approximately 9,000 subjects in a clinical 
setting. The standard deviation of the sample was 47 pounds. The CDC 
last published results from NHANES in 2000. Additional information 
on NHANES can be found at the following Web sites:
    (1) General information. http://www.cdc.gov/nchs/nhanes.htm.
    (2) Analytic and reporting guidelines. http://www.cdc.gov/nchs/data/nhanes/nhanes3/nh3gui.pdf.
    (3) Data files for 1999-2000 survey. http://www.cdc.gov/nchs/about/major/nhanes/NHANES99_00.htm.
    c. The FAA used most recent NHANES data set from surveys 
conducted in 1999 and 2000 to calculate the standard average 
passenger weights used in this advisory circular (AC). From this 
data set, the FAA separated out a separate data set of individuals 
who had not yet reached their 13th birthday to determine average 
child weight. From the remaining adult data set, the FAA removed all 
weight data that indicated the subject was clothed during the 
weighing and removed all data points more than two standard 
deviations from the mean. The FAA then calculated the average 
weights for males and females in the remaining data set.
    2. Standard average bag weights.
    To determine standard average weights for different types of 
bags, the FAA closely examined previous surveys conducted by 
operators, including several surveys conducted in response to FAA 
Notice 8400.40, Weight and Balance Control Programs for 10 to 19 
Seat Airplanes Operated Under 14 CFR 121. The results of those 
surveys are summarized in Table 2-1.
[GRAPHIC] [TIFF OMITTED] TN19AU04.008

Appendix 3. Sample Operational Loading Envelope

    1. Introduction.
    The following is an example of how to develop an operational 
loading envelope. For this example, a hypothetical 19-seat commuter 
category aircraft is used. Although this example uses inches to 
measure fuselage station, an operator may choose to use an index 
system for convenience.
    2. Assumptions for this example.
    a. Passenger weight. Because the aircraft is certificated under 
the commuter category of Title 14 of the Code of Federal Regulations 
(14 CFR) part 23 and because it is originally type-certificated for 
5 or more passenger seats, it would be appropriate to use the 
average weights listed in Chapter 3, Section 2. For this example, it 
is assumed that the operator does not have a carry-on bag program. 
Therefore, the operator should use a standard average passenger 
weight of 189 pounds in winter and 184 pounds in summer. For this 
example, a standard average passenger weight of 189 pounds is used. 
The operator also assumes that passengers are distributed throughout 
the cabin in accordance with the window-aisle-remaining method. Note 
that because this aircraft has only two window seats per row, the 
operator may reasonably assume that passengers begin seating 
themselves in the front of the cabin and select the most forward 
seat available.
    b. Bag weights. For this example, the operator assumes that a 
checked bag weighs 30 pounds and a plane-side loaded bag weighs 20 
pounds.
    c. Interior seating. For this example, consider a commuter 
category 19-seat aircraft with the interior seating diagram shown in 
Figure 3-1.

[[Page 51524]]

[GRAPHIC] [TIFF OMITTED] TN19AU04.009

    3. Curtailments for passenger seating variation.
    a. Establishing zones. The operator elects to separate the 
passenger cabin into three zones. Zone 1 will contain rows 1 to 3, 
zone 2 will contain rows 4 to 6, and zone 3 will contain rows 7 to 
9.
    b. Determining the centroid of each zone. When using cabin 
zones, an operator assumes that all passengers are sitting at the 
centroid of their zone. To find the centroid of each zone--
    (1) Multiply the number of seats in each row of the zone by the 
location of the row,
    (2) Add each number calculated in step 1, and
    (3) Divide the number in step 2 by the total number of seats in 
the zone.

    Note: For this sample aircraft, see Tables 3-1 through 3-3 
below.


[[Page 51525]]


[GRAPHIC] [TIFF OMITTED] TN19AU04.010

    c. Comparing loading assumptions. To determine the appropriate 
amount of curtailment, the operator should compare aircraft loading 
based on the window-aisle-remaining assumption with aircraft loaded 
based on the assumption that passengers are sitting at the centroid 
of their respective zones. An operator may determine the appropriate 
curtailment by comparing the moments resulting from these 
assumptions and identifying the loading scenarios that result in the 
most forward or aft center of gravity (CG) location. See Tables 3-4 
through 3-12 below.

[[Page 51526]]

    (1) Curtailment calculation for zone 1.
    [GRAPHIC] [TIFF OMITTED] TN19AU04.011
    

[[Page 51527]]


    (2) Curtailment calculation for zone 2.
    [GRAPHIC] [TIFF OMITTED] TN19AU04.012
    

[[Page 51528]]


    (3) Curtailment calculation for zone 3.
    [GRAPHIC] [TIFF OMITTED] TN19AU04.013
    
    (4) Determining the most adverse loading. It is important that 
an operator examine the above results for each zone and determine 
which loading scenario results in the greatest difference in 
moments. For zones 1 and 2, having two, three, or four passengers in 
the zone results in the largest difference between the moments. For 
zone 3, having four passengers in the zone results in the largest 
difference. In this case, the operator should curtail the 
manufacturer's loading envelope forward and aft by the sum of these 
moments, 36,666 inch-pounds, to account for the potential variation 
in passenger seating. In this example, the 36,666 inch-pounds is the 
sum of 11,340 from Table 3-6; 10,962 from Table 3-9; and 14,364 from 
Table 3-12.
    (5) Using actual seating location. Alternatively, an operator 
may reasonably avoid the above curtailment calculations by 
determining the actual seating location of

[[Page 51529]]

each passenger in the cabin. By eliminating potential variation in 
passenger seating, an operator would not need to make assumptions 
about passenger seating and would not need to curtail the loading 
envelope accordingly. An operator choosing to use actual seating 
location should have procedures in place to ensure that passengers 
sit in their assigned location.
    4. Other curtailments to the manufacturer's loading envelope.
    a. Variation in passenger weight. Because the operator in this 
example elects to use standard average weights on a small-cabin 
aircraft, an additional curtailment for potential variation in 
passenger weight is required. The operator should curtail the 
manufacturer's loading envelope by 23,791 inch-pounds forward and 
aft to account for the variation in passenger weight. A full 
explanation of this calculation is contained in Appendix 4.
    b. Variation in fuel density. Because the loading of fuel does 
not significantly change the CG of the aircraft, the operator would 
not need to provide a curtailment for variation in fuel density.
    c. Fuel movement in flight. For this sample aircraft, the 
manufacturer has considered the movement of fuel in flight. 
Therefore, the operator does not need to include additional 
curtailments in the operational loading envelope.
    d. Fluids. The sample aircraft does not have a lavatory or 
catering.
    e. Bags and freight. The sample aircraft has an aft bag 
compartment split into two sections. If the operator has procedures 
in place to restrict the movement of bags between the two sections, 
no additional curtailment to the envelope is required.
    f. In-flight movement of passengers and crewmembers. Because 
there are no flight attendants and the aircraft is not equipped with 
a lavatory, it is reasonable to assume that passengers or 
crewmembers will not move about the cabin in flight.
    g. Movement of flaps and landing gear. The manufacturer of the 
sample aircraft has considered the movement of flaps and landing 
gear in the development of its loading envelope. The operator does 
not need to include any additional curtailments in its operational 
loading envelope for the movement of those items.
    h. Fuel consumption. To ensure the sample aircraft remains 
within the manufacturer's CG limits as fuel is consumed, the 
operator should curtail the aft CG at weights less than the zero-
fuel weight by 8,900 inch-pounds. In this example, the 8,900 inch-
pounds is the fuel burn deviation that would bring the aircraft 
outside the aft CG limit during the course of flight.
    5. Operational loading envelope diagrams.
    a. Figure 3-2 below shows the operator's curtailments to the 
manufacturer's loading envelope, based on the assumptions made about 
variations in passenger seating and weight, as well as fuel 
consumption.
[GRAPHIC] [TIFF OMITTED] TN19AU04.014

    b. To expand the operational loading envelope, an operator could 
choose to use the actual seating location of passengers in the cabin 
and eliminate the curtailment for variations in passenger seating. 
Figure 3-3 below shows the expansion of the operational loading 
envelope.

[[Page 51530]]

[GRAPHIC] [TIFF OMITTED] TN19AU04.015

Appendix 4. Additional Curtailments to CG Envelopes To Account for 
Variations to Passenger Weights

    a. The use of average weights for small cabin aircraft requires 
consideration of an additional curtailment to the center of gravity 
(CG) envelope for passenger weight variations and male/female 
passenger ratio. This curtailment is in addition to the standard 
curtailments discussed in Chapter 2.
    (1) Passenger weight variation is determined by multiplying the 
standard deviation (from the source of the average passenger weight 
used) by the row factor from Table 4-1. The following table ensures 
a 95-percent confidence level of passenger weight variation, using 
the window-aisle-remaining seating method.

[[Page 51531]]

[GRAPHIC] [TIFF OMITTED] TN19AU04.016

    (2) Protect against the possibility of an all-male flight by 
subtracting the difference between the male and average passenger 
weight.
    (3) The sum of these two provides an additional weight to be 
used for CG curtailment, similar to the way in which passenger 
seating variation is calculated.
    b. If the operator chooses to use the passenger cabin zone 
concept (as described in Appendix 3) and apply this concept to 
account for variation in passenger weight, then the row factor in 
Table 4-1 corresponding to the number of rows in each zone should be 
used. For the purposes of this curtailment, the zone can be no 
smaller than two rows, if row count is used for passenger seating 
calculations. Therefore, if an operator chooses to use row count, 
the operator must use the row factor for two rows.
    c. Calculation of the curtailment passenger weight variation is 
decided by multiplying the standard deviation by the correction 
factor and adding the difference between male and female passenger 
weight. For example, assuming a 47 pound standard deviation, the 
difference between the average passenger weight and an all-male 
weight is 10 pounds (from 1999-2000 National Health and Nutrition 
Examination Survey (NHANES) data), and a sample aircraft with 9 rows 
in a 2-abreast configuration. The additional weight to be curtailed 
is determined as:

Weight for Additional Curtailment = (47 x 1.70) + (10) = 90 lbs

    d. For the example, the additional curtailment should be 
accomplished by assuming passenger loading at 90 pounds using the 
program method for passenger seating variation (e.g., window-aisle-
remaining). Using the window-aisle-remaining method, the additional 
curtailment in the example is determined to be 62,310 inch-pounds 
forward and aft. Table 4-2 displays the calculations used in this 
example.

    Note: The following definitions describe the parameters used in 
the sample:

     Seat Centroid: Location of passenger weight at seat.
     Seat Moment: Additional passenger weight x seat 
centroid.
     Total Weight: Sum of additional passenger weights 
(running total).
     Total Moment: Sum of additional passenger moments.
     Moment Deviation: Difference between total moment and 
moment generated by assuming additional passenger weight is located 
at the cabin centroid (323.8 in).

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Appendix 5. Options To Improve Accuracy

    A number of options are available that enable operators to 
deviate from standard assumed weights and may also provide relief 
from constraints required when assumed averages are used. These 
options include:
    (1) Surveys. Surveys may be accomplished for passenger weights 
(to include carry-on bags), checked baggage weights, male/female 
ratios and fuel densities. These surveys may be conducted for entire 
operator route systems, or by specific market or region. Surveys 
practices and data reduction must conform to the requirements 
defined in this advisory circular (AC). Use of surveys may allow an 
operator to use passenger and baggage weights less than the standard 
specified in this AC. Also, a survey may find that the assumed male/
female ratio is incorrect and appropriate adjustments must be made. 
For example, let's assume the following results from an approved 
passenger and baggage survey.

Male passenger weight (M) = 183.3 pounds
Female passenger weight (F) = 135.8 pounds
Difference between male and average passenger weights = 24.0 pounds
Standard deviation of total sample (Sigma) = 47.6 pounds
Male/female ratio (Pax Ratio) = 50.6 percent
Checked baggage weight = 29.2 pounds
Baggage checked plane-side = 21.3 pounds
Carry-on and personal items weight (CO Wt) = 10.4 pounds
Carry-on and personal items per passenger ratio (CO Ratio) = 0.82 
pounds
Survey conducted in summer months

    The resulting assumed passenger weight for loading is expressed 
as:

Passenger Weight = M x Pax Ratio + F x (1 - Pax Ratio) + CO Wt x CO 
Ratio

    And is determined as:

Summer Passenger Weight = 0.506 x 183.3 + (1 - 0.506) x 135.8 + 10.4 
x 0.82 = 169 lb
Winter Passenger Weight = 169 + 5 = 174 lb

    Survey results would also be used to determine the additional 
curtailment for variations to passenger weight. Assuming a 19-seat 
aircraft in 2-abreast configuration in our example, the additional 
weight to be curtailed would be:

Additional Weight for Curtailment = (47.6 x 1.70) + 24 = 104.9 lb

    Also in our example, the assumed checked baggage weight is 30 
pounds. Plane-side loaded bags would be assumed to weigh 20 pounds. 
(These weights are the standard average weights provided for a no-
carry-on baggage program as described in Chapter 3, Section 2).
    (2) Actual Weights. It is permissible to use actual weights in 
lieu of standard average, segmented, or survey-derived average 
weights (if applicable). Parameters that may use actual weights 
include passenger weights, checked baggage weights, carry-on bag 
weights, crew weights, and fuel density/weight.
    (3) Passenger Cabin Zones and Row Count. Passenger cabins may be 
split up into zones provided an acceptable procedure for 
determination of passenger seating is included (e.g., use of seat 
assignments or crew counts seated passengers by zone). If zones are 
used, it may be reasonable for the operator to reduce the center of 
gravity (CG) passenger seating curtailment suggested in this AC by 
accommodating variations within each individual zone separately and 
totaling the results. Passenger row count allows the operator to 
eliminate the seating variation by accounting for where the 
passenger is actually seated.
    An example of use of passenger zones follows.
    Assume an aircraft interior as displayed in Figure 5-1.

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    Assume that for weight and balance purposes, it is desirable to 
break the cabin up into three passenger zones. The passenger zones 
will be determined as zone 1 (rows 1-3), zone 2 (rows 4-6), and zone 
3 (rows 7-9). Use of the window-aisle-remaining method will be used 
in each zone to provide a total curtailment to the CG envelope. (For 
this sample aircraft, window-aisle-remaining method simply becomes 
forward and aft end loading). For each zone, a zone centroid must be 
calculated by counting the total number of seats and averaging their 
location.

Zone 1 centroid = (2 x 198.0 + 2 x 228.0 + 2 x 258.0) / (2 + 2 + 2) 
= 228.0 in.
Zone 2 centroid = (2 x 289.0 + 2 x 318.0 + 2 x 347.0) / (2 + 2 + 2) 
= 318.0 in.
Zone 3 centroid = (2 x 377.0 + 2 x 407.0 + 3 x 436.0) / (2 + 2 + 3) 
= 410.9 in.

    Assuming the standard winter passenger weight of 195 pounds is 
used for the curtailment, the calculation of total moment is 
required for comparison to moment assuming each passenger is seated 
at the centroid of each passenger zone. The total moment is found by 
summing the individual moments calculated at each occupied seat in 
the window-aisle-remaining progression.

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    The curtailment for passenger seating variation is determined by 
adding the largest delta moments from each of the passenger zones. 
In our example, the curtailment to the forward CG limit for 
passenger seating variation is -37,719 inch-pounds (-11,700 + -
11,310 + - 4,709). Similarly, curtailment to the aft limit of the CG 
envelope using window-aisle-remaining method loading from the most 
aft seat row moving forward (in each zone) would result in an 
adjustment of 37,719 inch-pounds. Figures 5-2 through 5-4 
graphically show the curtailments for each passenger zone through 
use of forward and aft end loading using our example.

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    (4) Actual M/F Counts. Loading systems may use separate male and 
female assumed passenger weights for each operation. If the 
operator's weight and balance program is approved for use of male/
female weights, then the operator must count the number of male 
passengers and female passengers separately. The male and female 
weights used may be from the development of standard passenger 
weight as described in this AC or they may be determined through an 
operator-developed survey as also described in this AC. Use of male/
female weights may be for entire operations or for a particular 
route and/or region of flying.
    An example of how male/female ratios can be applied to weight 
and balance systems follows.
    Assuming the operator is using the survey results as described 
in subparagraph (1) above, the assumed male and female passenger 
weights, including average carry-on baggage, are computed as:

Male passenger weight (summer) = 183.3 + 10.4 x 0.82 = 192 lb
Male passenger weight (winter) = 192 + 5 = 197 lb
Female passenger weight (summer) = 135.8 + 10.4 x 0.82 = 144 lb
Female passenger weight (winter) = 144 + 5 = 149 lb
The weight and balance manifest would provide for identification of 
male/female identification and the passenger weights would be summed 
accordingly. For instance, 7 male and 11 female passengers would 
result in a total passenger weight of (7 x 192) + (11 x 144) = 2,928 
pounds.
    (5) Adolescent (Child) Weights. In most circumstances, an 
operator may consider any passenger less than 13 years of age, who 
is occupying a seat, to weigh less than an adult passenger as 
described in this AC. The standard adolescent child weights can be 
found in Table 3-1 of Chapter 3.
    (6) Standard Weights With Approved No-Carry-on Baggage Program.

Summer Passenger Weight = 184 lb
Winter Passenger Weight = 189 lb
Checked Baggage Weight = 30 lb each
Baggage Checked Plane-side = 20 lb each

Inclusion in the no-carry-on baggage program does not preclude use 
of actual or surveyed weights for passengers, carry-on/personal 
items, checked baggage, or baggage checked plane-side.
    (7) Automation. Automation may also be used to provide a more 
accurate weight and balance program. Examples of automation include 
use of seat assignments for the determination of passenger moment 
and historical seating to determine passenger moment.

Appendix 6. Sample CG Envelope Development

    Outlined below is an example of the development of a center of 
gravity (CG) envelope construction for a 19-seat commuter category 
aircraft. The sample system uses a CG diagram displayed in inches. 
Operators' systems may use a variety of methods to display CG 
diagram, including an Index system detailed in Chapter 2, Section 2 
and in Appendix 3.

Sample Development of Weight and Balance System for 19-Seat Aircraft

    a. CG Envelope Construction. The certified CG envelope provided 
by the manufacturer must be examined for the following curtailments.
    (1) Variations to Passenger Seating (Outlined in Chapter 2). In 
this example, the window-aisle-remaining method was used considering 
a passenger weight of 189 pounds and using 3 passenger zones, where 
zone 1 is defined as rows 1-3, zone 2 is defined as rows 4-6, and 
zone 3 is defined as rows 7-9. (189 lb/pax is used since the 
operator will be using a no-carry-on baggage program as detailed 
later on in this sample exercise). The resulting curtailment for use 
of 3 passenger zones is 36,600 inch-pounds forward and aft.
    (2) Variations to Passenger Weight (Outlined in Appendix 4). 
Since the sample

[[Page 51538]]

aircraft falls into the group of aircraft requiring full evaluation 
of small cabin aircraft rules, application of a curtailment due to 
variations to passenger weight is required.
    (a) Use of Passenger Zone Concept for Curtailment. Considering 
three cabin zones with each zone containing three rows in a 2-
abreast configuration, the required row factor (see Appendix 4, 
Table 4-1) is 2.41. The row factor is multiplied by the standard 
deviation and the difference between average male and average female 
weights is added to provide the additional weight consideration. In 
our example, the standard deviation is calculated from the National 
Health and Nutrition Examination Survey (NHANES) data as 47 pounds, 
and the difference between average all-male and average passenger 
weights is 10 pounds. The resulting additional weight for 
curtailment is 47 x 2.41 + 10 = 123 pounds. This additional weight 
is applied per the window-aisle-remaining concept for each cabin 
zone independently and the results are summed to determine the 
amount of curtailment. In this case, the curtailment is found to be 
23,791 inch-pounds forward and aft.
    (b) Use of Row Count for Curtailment. When using row count, the 
required row factor is 2.96. The row factor is multiplied by the 
standard deviation and the difference between average male and 
average female weights is added to provide the additional weight 
consideration. In our example, the standard deviation is calculated 
from the NHANES data as 47 pounds, and the difference between 
average all-male and average passenger weights is 10 pounds. The 
resulting additional weight for curtailment is 47 x 2.96 + 10 = 149 
pounds. This additional weight is applied as if a 2-row passenger 
zone concept is used for passenger seating. The resulting 
curtailment is determined to be 16,657 inch-pounds forward and aft.
    (3) Variations to Fuel Density. Since the loading of fuel does 
not significantly shift the CG for the aircraft, it is not necessary 
to correct for variations in fuel density (i.e., the correction is 
negligible).
    (4) Fuel Movement in Flight. Fuel movement has been considered 
by the manufacturer in the development of the certified envelope, 
making an additional curtailment unnecessary.
    (5) Fluids. The sample aircraft does not have a lavatory and 
there is no catering.
    (6) Baggage and Freight. The sample aircraft provides a baggage 
web in the aft baggage compartment, splitting the compartment into 
forward and aft sections. In our example, we assume the operator is 
making full use of this web and the movement of baggage is 
restricted. No curtailment is necessary.
    (7) In Flight Movement of Passengers and Crew. Since there are 
no flight attendants and no lavatories on the sample aircraft, it is 
reasonable to assume that the passengers will remain in their seats 
for the duration of the flight. Therefore, it is not necessary to 
curtail the limits for passenger and crew in-flight movement.
    (8) Movement of Flaps and Landing Gear. In the case of the 
sample aircraft, the manufacturer has included consideration of flap 
and landing gear movement in the development of the certified 
envelope. No additional curtailment is necessary.
    (9) Fuel consumption. The fuel vector for the sample aircraft 
provides a small aft movement that requires a -8,900 inch-pounds 
curtailment to the aft zero fuel weight limits to ensure the 
aircraft does not exceed the aft limit as fuel is burned. This 
equates to a -0.8 inch curtailment at an estimated operational empty 
weight of 11,000 pounds with a linear transition to a -0.6 inch 
curtailment at MZFW of 16,155 pounds. In this example, the 8,900 
inch-pounds is the fuel burn deviation that would bring the aircraft 
outside the aft CG limit during the course of flight.
    b. Three operational curtailments to the sample aircraft CG 
envelope are required. These are for variations to passenger seating 
and passenger weight, and fuel burn-off. Figure 6-1 displays the 
operational CG envelope highlighting the required curtailments.
BILLING CODE 4910-13-P

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    c. Assuming the operator wishes to widen the envelope, use of 
actual passenger seating (row count) may be used to eliminate the 
curtailment required for variations to passenger seating. Figure 6-2 
displays a CG envelope that makes use of actual passenger seating.

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    d. No-Carry-On Baggage Program. This example assumes a no-carry-
on bag program. This allows consideration of reduced passenger 
weight to 184 pounds (summer) and 189 pounds (winter). Carry-on bags 
checked at the gate or ``plane-side loaded'' will be counted as 20 
pounds/bag. Bags checked at the ticket counter will remain at 30 
pounds/bag.

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[FR Doc. 04-18905 Filed 8-18-04; 8:45 am]
BILLING CODE 4910-13-C