[Federal Register Volume 71, Number 230 (Thursday, November 30, 2006)]
[Rules and Regulations]
[Pages 69186-69190]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E6-20277]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 25

[Docket No. NM354; Special Conditions No. 25-336-SC]


Special Conditions: Boeing Commercial Airplane Group, Boeing 
Model 777 Series Airplane; Overhead Cross Aisle Stowage Compartments

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final special conditions.

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SUMMARY: These special conditions are issued for the Boeing Model 777 
series airplanes. This airplane will have novel or unusual design 
features associated with overhead cross aisle stowage compartments. The 
applicable airworthiness regulations do not contain adequate or 
appropriate safety standards for these design features. These special 
conditions contain the additional safety standards the Administrator 
considers necessary to establish a level of safety equivalent to that 
established by the existing airworthiness standards.

EFFECTIVE DATE: November 15, 2006.

FOR FURTHER INFORMATION CONTACT: Jayson Claar, FAA, Airframe/Cabin 
Branch, ANM-115, Transport Airplane Directorate, Aircraft Certification 
Service, 1601 Lind Avenue SW., Renton, Washington, 98057-3356; 
telephone (425) 227-2194; facsimile (425) 227-1232.

SUPPLEMENTARY INFORMATION:

Background

    On April 20, 2005, Boeing Commercial Airplane Group, Seattle, 
Washington, applied for a supplemental type certificate to permit 
installation of overhead cross aisle stowage compartments in Boeing 777 
series airplanes. The Boeing Model 777 series airplanes are large twin 
engine airplanes with four or five pairs of Type A exits. The Boeing 
777 airplanes can be configured with various passenger capacities and 
ranges.
    The regulations do not address the novel and unusual design 
features associated with the installation of overhead cross aisle 
stowage compartments installed on the Boeing Model 777, making these 
special conditions necessary. Generally, the requirements for overhead 
stowage compartments are similar to stowage compartments in remote crew 
rest compartments (i.e., located on lower lobe, main deck or overhead) 
already in use on Boeing Model 777 and 747 series

[[Page 69187]]

airplanes. Remote crew rest compartments have been previously installed 
and certified in the main passenger cabin area, above the main 
passenger area, and below the passenger cabin area adjacent to the 
cargo compartment of the Boeing Model 777-200, and -300 series 
airplanes.

Type Certification Basis

    Under the provisions of Sec.  21.101, Boeing Commercial Airplane 
Group must show that the Boeing Model 777, as changed, continues to 
meet the applicable provisions of the regulations incorporated by 
reference in Type Certificate No. T00001SE or the applicable 
regulations in effect on the date of application for the change. The 
regulations incorporated by reference in the type certificate are 
commonly referred to as the ``original type certification basis.'' The 
regulations incorporated by reference in Type Certificate No. T00001SE 
for the Boeing Model 777 series airplanes include Title 14 Code of 
Federal Regulations (CFR), part 25, as amended by Amendments 25-1 
through 25-100, with exceptions, for various models. Refer to Type 
Certificate No. T00001SE, as applicable, for a complete description of 
the certification basis for this model, including certain special 
conditions that are not relevant to these special conditions.
    If the Administrator finds the applicable airworthiness regulations 
(part 25 as amended) do not contain adequate or appropriate safety 
standards for the Boeing Model 777 because of a novel or unusual design 
feature, special conditions are prescribed under the provisions of 
Sec.  21.16.
    In addition to the applicable airworthiness regulations and special 
conditions, the Boeing Model 777 must comply with the fuel vent and 
exhaust emission requirements of 14 CFR part 34 and the noise 
certification requirements of 14 CFR part 36.
    The FAA issues special conditions, as defined in Sec.  11.19, under 
Sec.  11.38, and they become part of the type certification basis under 
Sec.  21.101.
    Special conditions are initially applicable to the model for which 
they are issued. Should the applicant apply for a change to modify any 
other model included on the same type certificate to incorporate the 
same or similar novel or unusual design feature, the special conditions 
would also apply to the other model under Sec.  21.101.

Novel or Unusual Design Features

    The Boeing Model 777 will incorporate the following novel or 
unusual design features: the installation of powered lift-enabled 
stowage compartments that rise into the overhead area and lower into 
the cabin.
    The overhead cross aisle stowage compartments are configured to 
allow stowage of galley type standard containers as well as coats, 
bags, and other items typically stowed in closets or bins. These 
stowage compartments may be located above the emergency exit cross 
aisles of Boeing Model 777 series airplanes. Because the compartment is 
lowered into the main cabin, it could affect egress if it cannot be 
raised again. The overhead compartment may lower into a cross aisle as 
defined in Sec.  25.813, but it may also lower into other potential 
egress paths. For the purposes of these special conditions, the same 
criteria apply, whether or not the egress path is required by Sec.  
25.813. Therefore, as used in these special conditions, the term 
``overhead cross aisle stowage compartment'' addresses all such 
compartments.
    Each stowage compartment is accessed from the main deck by a 
powered lift that lowers and raises the stowage compartment between the 
overhead and the main deck. In addition, the lift can be hand cranked 
down and up in the event of a power or lift motor failure. A smoke 
detection system will be provided in the overhead cross aisle stowage 
compartments.

Discussion of the Special Conditions

    In general, the requirements listed in these special conditions for 
overhead cross aisle stowage compartments are similar to those 
previously approved for overhead crew rest compartments in earlier 
certification programs, such as for the Boeing Model 777 and Model 747 
series airplanes. These special conditions establish compartment 
access, power lift, electrical power, smoke/fire detection, fire 
extinguisher, fire containment, smoke penetration, and compartment 
design criteria for the overhead cross aisle stowage compartments. The 
overhead stowage compartments are not a direct analogy to stowage 
compartments in remote crew rest compartments installed and certified 
for Boeing Model 777 series airplanes, but the safety issues raised are 
similar. Features similar to those considered in the development of 
previous special conditions for fire protection will be included here 
also. The requirements provide an equivalent level of safety to that 
provided by other Boeing Model 777 series airplanes with similar 
overhead compartments.

Operational Evaluations and Approval

    The FAA's Aircraft Certification Service will administer these 
special conditions, which specify requirements for design approvals 
(that is, type design changes and supplemental type certificates) of 
overhead cross aisle stowage compartments.
    The Aircraft Evaluation Group of the FAA's Flight Standards Service 
must evaluate and approve the operational use of overhead cross aisle 
stowage compartments prior to use. The Aircraft Evaluation Group must 
receive all instructions for continued airworthiness, including service 
bulletins, prior to the FAA accepting and issuing approval of the 
modification.

Special Condition No. 1, Compartment Access and Placards

    Appropriate placards, or other means, are required to address door 
access and locking to prohibit or prevent passenger access, and 
operation of the overhead storage compartment. There must also be a 
means to preclude anyone from being trapped inside the stowage 
compartment, if it is large enough for a person to enter. If there is 
more than one door providing access, each door must be equipped with 
these means.

Special Condition No. 2, Power Lift

    The power lift must be designed so the overhead stowage compartment 
will not jam in the down position, even if lowered on top of a hard 
structure. The lift must operate at a speed, and stop above the floor 
at such a height, that allows anyone underneath the compartment to move 
clear without injury. The lift controls must be placed clear of the 
compartment door and must be pressed continuously for lift operation. 
Training on power lift operation procedures must be added to 
appropriate manuals.

Special Condition No. 3, Manual Operation

    There must be a means to manually operate the lift that is 
independent of the electrical drive system. The lift must be operable 
by a range of occupants, including a fifth percentile female. The 
manual means must be capable of lowering the overhead stowage 
compartment quickly to the main deck to fight a fire. The manual system 
must be capable of raising the compartment quickly so the cross aisle 
or other egress path (if applicable) is not blocked in an emergency. If 
electrical or manual power is removed, there must be a means, such as a 
brake, to prevent the compartment from unrestricted movement, i.e., 
falling. Training on

[[Page 69188]]

manual operation procedures must be added to appropriate manuals.

Special Condition No. 4, Handheld Fire Extinguisher

    For compartments larger than 25 cubic feet, a handheld fire 
extinguisher appropriate to fight the kinds of fire likely to occur in 
the overhead stowage compartment must be provided. This handheld fire 
extinguisher must be adjacent to the overhead compartment. This 
extinguisher must be in addition to those required for the passenger 
cabin.

Special Condition No. 5, Fire Containment

    This special condition requires either the installation of a 
manually activated fire extinguishing system that is accessible from 
outside the overhead stowage compartment, or a demonstration that the 
crew could satisfactorily perform the function of extinguishing a fire 
under the prescribed conditions. A manually activated built-in fire 
extinguishing system would be required only if a crewmember could not 
successfully locate and get access to the fire during a demonstration 
where the crewmember is responding to the alarm. For the duration of 
the flight, the system must have adequate capacity to suppress any fire 
occurring in the stowage compartment considering the fire threat, 
volume of the compartment, and the ventilation rate.

Special Condition No. 6, Smoke Penetration

    The design of the compartment must provide means to exclude 
hazardous quantities of smoke or extinguishing agent originating in the 
compartment from entering other occupied areas. The means must take 
into account the time period during which the compartment may be 
accessed to manually fight a fire, if applicable.
    Smoke entering any other compartment occupied by crewmembers or 
passengers, when access to the stowage compartment is opened to 
manually fight a fire, must dissipate within five minutes after the 
access to the stowage compartment is closed.
    During the one-minute smoke detection time (see Special Condition 
No. 7), penetration of a small quantity of smoke (one that would 
dissipate within 3 minutes under normal ventilation conditions) from 
this overhead stowage compartment into an occupied area on this 
airplane configuration would be acceptable based on the limitations 
placed in this and other associated special conditions. These special 
conditions place sufficient restrictions in the quantity and type of 
material allowed in the overhead stowage compartment that threat from a 
fire in this remote area would be equivalent to that experienced on the 
main cabin.
    If a built-in fire extinguishing system is used in lieu of manual 
fire fighting, then the fire extinguishing system must be designed so 
that no hazardous quantities of extinguishing agent will enter other 
compartments occupied by passengers or crew.

Special Condition No. 7, Compartment Design Criteria

    The material used to construct the overhead stowage compartment 
must meet the flammability requirements for compartment interiors in 
Sec.  25.853 and be fire resistant. Depending on the size of the 
compartment, certain fire protection features of Class B cargo 
compartments are also required. Enclosed stowage compartments equal to 
or exceeding 25 ft\3\ in interior volume must be provided with a smoke 
or fire detection system to ensure that a fire can be detected within a 
one-minute detection time. This is the same requirement as has been 
applied to remote crew rest compartments.
    Enclosed stowage compartments equal to or greater than 57 ft\3\ in 
interior volume but less than or equal to 200 ft\3\, must have a liner 
that meets the requirements of Sec.  25.855 for a Class B cargo 
compartment. The overhead stowage compartment may not be greater than 
200 ft\3\ in interior volume. The in-flight accessibility of very large 
enclosed stowage compartments and the subsequent impact on the 
crewmember's ability to effectively reach any part of the compartment 
with the contents of a handheld fire extinguisher would require 
additional fire protection considerations similar to those required for 
inaccessible compartments such as Class C cargo compartments.
    The overhead stowage compartment smoke or fire detection and fire 
suppression systems (including airflow management features which 
prevent hazardous quantities of smoke or fire extinguishing agent from 
entering any other compartment occupied by crewmembers or passengers) 
is considered complex in terms of paragraph 6d of Advisory Circular 
(AC) 25.1309-1A, ``System Design and Analysis.'' The FAA considers 
failure of the overhead stowage compartment fire protection system 
(that is, smoke or fire detection and fire suppression systems) in 
conjunction with an overhead stowage fire to be a catastrophic event. 
Based on the ``Depth of Analysis Flowchart'' shown in Figure 2 of AC 
25.1309-1A, the depth of analysis should include both qualitative and 
quantitative assessments (reference paragraphs 8d, 9, and 10 of AC 
25.1309-1A).
    The requirements to enable crewmember(s) quick access to the 
overhead stowage compartment and to locate a fire source inherently 
places limits on the amount of baggage stowed and the size of the 
overhead stowage compartment. The overhead stowage compartment is 
limited to stowage of galley type standard containers as well as coats, 
bags, and other items typically stowed in closets or bins. It is not 
intended to be used for the stowage of other items. The design of such 
a system to include other items may require additional special 
conditions to ensure safe operation.

Discussion of Comments

    Notice of proposed special conditions No. 25-06-09-SC for the 
Boeing Model 777-200 series airplanes was published in the Federal 
Register on October 18, 2006 (71 FR 61432). An amended proposed notice 
of special conditions No. SC-06-29A-SC for the Boeing Model 777 series 
airplanes was published in the Federal Register on November 2, 2006 (71 
FR 64478). No comments were received, and the special conditions are 
adopted as proposed, except for clarifying changes.

Applicability

    These special conditions are applicable to the Boeing Model 777 
series airplanes with overhead cross aisle stowage compartments. Should 
Boeing Commercial Airplane Group apply later for a change to Type 
Certificate No. T00001SE to include another model on the same type 
certificate incorporating the same novel or unusual design feature, the 
special conditions would apply to that model as well.
    Under standard practice, the effective date of final special 
conditions would be 30 days after the date of publication in the 
Federal Register, however, as the certification date for the Boeing 777 
series is imminent, the FAA finds that good cause exists for make these 
special conditions effective upon issuance.

Conclusion

    This action affects only certain novel or unusual design features 
on the Boeing Model 777 series airplanes. It is not a rule of general 
applicability and affects only the applicant who applied to the FAA for 
approval of these features on the airplane.

[[Page 69189]]

List of Subjects in 14 CFR Part 25

    Aircraft, Aviation safety, Reporting and recordkeeping 
requirements.

    The authority citation for these special conditions is as follows:

    Authority: 49 U.S.C. 106(g), 40113, 44701, 44702, 44704.

The Special Conditions

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the following special conditions are issued as part of 
the type certification basis for Boeing Model 777 series airplanes. 
Each overhead cross aisle stowage compartment and the adjacent area, 
including the structural frame, mechanical system and drive motor, must 
meet the following requirements:
    1. Compartment Access and Placards. There must be a means to 
prohibit or prevent passengers from entering or operating the overhead 
cross aisle stowage compartment. Placards prohibiting access are 
acceptable. If a compartment is large enough for a person to enter, 
there must be a means to preclude anyone from being trapped inside the 
stowage compartment. If a latching/locking mechanism is installed, the 
door must be capable of being opened from the outside without the aid 
of special tools. The mechanism must not prevent opening from the 
inside of the stowage at any time.
    2. Power Lift. There must be a means such as a load or force 
limiter to protect the overhead cross aisle stowage compartment power 
lift from failure or jamming in the down position in the event it is 
lowered on top of a hard structure such as a galley cart.
    (a) The lift controls must be placed so the operator is clear of 
the lift and designed such that the controls must be pressed 
continuously for lift operation.
    (b) The lift must raise and lower the stowage compartment at a slow 
enough rate, and stop above the floor at such a height, that anyone 
underneath can easily move clear without injury.
    (c) Stowage compartment operation training procedures must be added 
to the appropriate flight attendant manuals.
    3. Manual Lift. There must be a means in the event of failure of 
the aircraft's main power system, or of the powered overhead cross 
aisle stowage compartment lift system, for manually activating the lift 
system.
    (a) This manual means must be independent of the electrical drive 
system
    (b) The manual means must be accessible and operable by a range of 
occupants, including a fifth percentile female.
    (c) The manual means must be capable of lowering the stowage 
compartment to the main deck quickly enough to fight a fire in the 
stowage compartment before overhead cross aisle stowage compartment 
fire containment is compromised.
    (d) The manual means must be capable of quickly raising the stowage 
compartment such that the cross aisle, or other egress path is not 
blocked in the event of an emergency.
    (e) Stowage compartment firefighting training procedures must be 
added to the appropriate manuals.
    (f) The lift system must include a means, such as a brake, to 
retain the overhead cross aisle stowage compartment in any position of 
travel when the manual or electric drive force is removed.
    4. Fire Extinguisher. The means to manually fight a fire in the 
overhead cross aisle stowage compartment must consider the additional 
stowage volume and time required to manually lower the compartment 
after indication. For compartments larger than 25 ft\3\ the following 
equipment must be provided directly adjacent to each overhead cross 
aisle stowage compartment: at least one approved handheld fire 
extinguisher, in addition to the fire extinguisher requirements of 
Sec.  25.851 and Sec.  121.309, appropriate for the kinds of fires 
likely to occur within the overhead stowage compartment.
    5. Fire Containment. Fires originating within the overhead cross 
aisle stowage compartment must be controlled for the duration of the 
flight without a crewmember having to access the compartment. 
Alternatively, the design of the access provisions must allow 
crewmembers equipped for firefighting to have unrestricted access to 
the compartment. If the latter approach is elected it must be 
demonstrated that a crewmember has sufficient access to enable them to 
extinguish a fire. The time for a crewmember on the main deck to react 
to the fire alarm, (and, if applicable, to don the firefighting 
equipment and to open the compartment) must not exceed the flammability 
and fire containment capabilities of the stowage compartment.
    6. Smoke Penetration. There must be a means provided to exclude 
hazardous quantities of smoke or extinguishing agent originating in the 
overhead cross aisle stowage compartment from entering any other 
compartment occupied by crewmembers or passengers. If access is 
required to comply with Special Condition No. 5, this means must 
include the time period when accessing the stowage compartment to 
manually fight a fire. Smoke entering any other compartment occupied by 
crewmembers or passengers, when access to the stowage compartment is 
opened to manually fight a fire, must dissipate within five minutes 
after the access to the stowage compartment is closed. Prior to the one 
minute smoke detection time (reference note 2 in paragraph (7)) 
penetration of a small quantity of smoke (one that would dissipate 
within 3 minutes under normal ventilation conditions) from the stowage 
compartment into an occupied area is acceptable. Flight tests must be 
conducted to show compliance with this requirement.
    7. Compartment Design Criteria. The overhead cross aisle stowage 
compartment must be designed to minimize the hazards to the airplane in 
the event of a fire originating in the stowage compartment.
    (a) Fire Extinguishing System. If a built-in fire extinguishing 
system is used in lieu of manual firefighting, then the fire 
extinguishing system must be designed so no hazardous quantities of 
extinguishing agent will enter other compartments occupied by 
passengers or crew. The system must have adequate capacity to suppress 
any fire occurring in the stowage compartment, considering the fire 
threat, volume of the compartment, and the ventilation rate.
    (b) Compartment Size. All overhead cross aisle stowage compartments 
must meet the design criteria given in the table below. As indicated by 
the table below, enclosed stowage compartments greater than 200 ft\3\ 
in interior volume are not addressed by this special condition.

                                      Stowage Compartment Interior Volumes
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  Fire protection features        Less than 25 ft\3\         25 ft\3\ to 57 ft\3\        57 ft\3\ to 200 ft\3\
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Materials of Construction     Yes.......................  Yes.......................  Yes.
 \1\.
Detectors \2\...............  No........................  Yes.......................  Yes.

[[Page 69190]]

 
Liner \3\...................  No........................  Yes.......................  Yes.
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\1\ Material
 The material used to construct each enclosed stowage compartment must be at least fire resistant and must meet
  the flammability standards established for interior components (that is, 14 CFR Part 25 Appendix F, Parts I,
  IV, and V) per the requirements of Sec.   25.853. For compartments less than 25 ft\3\ in total interior
  volume, the design must ensure the ability to contain a fire likely to occur within the compartment under
  normal use.
\2\ Detectors
 Enclosed stowage compartments equal to or exceeding 25 ft\3\ in total interior volume must be provided with a
  smoke or fire detection system to ensure that a fire can be detected within one minute. Flight tests must be
  conducted to show compliance with this requirement. Each system (or systems) must provide:
 (a) A visual indication in the flight deck within one minute after the start of a fire;
 (b) A warning in the main passenger cabin. This warning must be readily detectable by a flight attendant,
  taking into consideration the positioning of flight attendants throughout the main passenger compartment
  during various phases of flight.
\3\ Liner
 If it can be shown the material used to construct the stowage compartment meets the flammability requirements
  of a liner for a Class B cargo compartment (that is, Sec.   25.855 at Amendment 25-93 and Appendix F, part I,
  paragraph (a)(2)(ii)), in addition to the above \1\ Material requirement, then no liner would be required for
  enclosed stowage compartments equal to or greater than 25 ft\3\ in total interior volume but less than 57
  ft\3\ in total interior volume. For all enclosed stowage compartments equal to or greater than 57 ft\3\ in
  total interior volume but less than or equal to 200 ft\3\, a liner must be provided that meets the
  requirements of Sec.   25.855 for a Class B cargo compartment.


    Issued in Renton, Washington, on November 15, 2006.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
 [FR Doc. E6-20277 Filed 11-29-06; 8:45 am]
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