[Federal Register Volume 62, Number 112 (Wednesday, June 11, 1997)]
[Proposed Rules]
[Pages 31766-31769]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-15174]


=======================================================================
-----------------------------------------------------------------------

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 96-CE-58-AD]
RIN 2120-AA64


Airworthiness Directives; Fairchild Aircraft Incorporated Models 
SA226-TC, SA226-T, SA226-T(B), and SA226-AT Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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

SUMMARY: This document proposes to adopt a new airworthiness directive 
(AD) that would apply to certain Fairchild Aircraft Incorporated 
(Fairchild) Models SA226-TC, SA226-T, SA226-T(B), and SA226-AT 
airplanes. The proposed AD would require inspecting the center flap 
hinge and wing trailing edge ribs at the flap actuator attach brackets 
for cracks and if no cracks are found, installing a doubler on the rib, 
or replacing a cracked rib with a new rib assembly that is reinforced 
with a doubler. Fatigue cracks at the center flap hinge and the support 
link has resulted in concentrated stress on the wing trailing edge ribs 
which prompted the proposed action. The actions specified by the 
proposed AD are intended to prevent asymmetrical flap deflection 
forcing the airplane into an uncommanded roll and

[[Page 31767]]

could cause loss of control of the airplane.

DATES: Comments must be received on or before August 11, 1997.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Central Region, Office of the Assistant Chief 
Counsel, Attention: Rules Docket No. 96-CE-58-AD, Room 1558, 601 E. 
12th Street, Kansas City, Missouri 64106. Comments may be inspected at 
this location between 8 a.m. and 4 p.m., Monday through Friday, 
holidays excepted.
    Service information that applies to the proposed AD may be obtained 
from Fairchild Aircraft Inc., P.O. Box 32486, San Antonio, Texas, 
78284; telephone (210) 824-9421. This information also may be examined 
at the Rules Docket at the address above.

FOR FURTHER INFORMATION CONTACT: Mr. Hung Viet Nguyen, Aerospace 
Engineer, FAA, Fort Worth Airplane Certification Office, 2601 Meacham 
Boulevard, Fort Worth, Texas 76193-0150; telephone (817) 222-5155; 
facsimile (817) 222-5960.

SUPPLEMENTARY INFORMATION:

Comments Invited

    Interested persons are invited to participate in the making of the 
proposed rule by submitting such written data, views, or arguments as 
they may desire. Communications should identify the Rules Docket number 
and be submitted in triplicate to the address specified above. All 
communications received on or before the closing date for comments, 
specified above, will be considered before taking action on the 
proposed rule. The proposals contained in this notice may be changed in 
light of the comments received.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the proposed rule. All 
comments submitted will be available, both before and after the closing 
date for comments, in the Rules Docket for examination by interested 
persons. A report that summarizes each FAA-public contact concerned 
with the substance of this proposal will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this notice must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket No. 96-CE-58-AD.'' The postcard will be date stamped and 
returned to the commenter.

Availability of NPRMs

    Any person may obtain a copy of this NPRM by submitting a request 
to the FAA, Central Region, Office of the Assistant Chief Counsel, 
Attention: Rules Docket No. 96-CE-58-AD, Room 1558, 601 E. 12th Street, 
Kansas City, Missouri 64106.

Events Leading to the Proposed AD

    The FAA has received reports of three incidents on certain 
Fairchild SA226 series airplanes with fatigue cracks in the wing 
trailing edge rib at the center flap hinge. Further investigation shows 
that the cracking is relieving the stress load at the support link. 
This prevents the flaps from extending to full deflection, which could 
result in asymmetrical flap deflection and cause the airplane to go 
into an uncommanded roll.

Related Service Information

    Fairchild has issued Service Bulletin (SB) SB 57-016, Issued: June 
25, 1981; Revised: December 9, 1981, that specifies procedures for 
inspecting the wing trailing edge ribs for cracks, if no cracks are 
found, installing reinforcement doublers on the ribs, and replacing 
ribs that have cracks with new rib assemblies.

(Note: The compliance time in this AD takes precedence over the 
compliance time in the Fairchild Service Bulletin referenced above.)

FAA's Determination

    After examining the circumstances and reviewing all available 
information related to the incidents and service information described 
above, the FAA has determined that AD action should be taken to prevent 
asymmetrical flap deflection forcing the airplane into an uncommanded 
roll and could cause loss of control of the airplane.

Explanation of the Provisions of the Proposed AD

    Since an unsafe condition has been identified that is likely to 
exist or develop in other Fairchild Models SA226-TC, SA226-T, SA226-
T(B), and SA226A-T airplanes of the same type design, the proposed AD 
would require:

--Inspecting wing trailing edge ribs at wing stations (WS) 98.385 and 
100.635 for cracks,
--Replacing any cracked rib with a new rib assembly (part number (P/N) 
27-31085-1/2 or 27-31086-1/2 or FAA equivalent), and
--Installing a reinforcement doubler (P/N 27K36075-7 or FAA 
equivalent), whether or not cracks are found.

Cost Impact

    The FAA estimates that 240 airplanes in the U.S. registry would be 
affected by the proposed AD, that it would take approximately 100 
workhours per airplane to accomplish the proposed installation of the 
doubler and 180 workhours per airplane to accomplish the proposed 
installation of the new rib assembly and doubler, and that the average 
labor rate is approximately $60 an hour. Parts cost approximately $133 
for both wing rib assemblies per airplane. The doubler can be 
manufactured from local materials. Based on these figures, the total 
cost impact of the proposed AD on U.S. operators is estimated to be 
$2,623,920 for the U.S. fleet or $10,933 per airplane for the rib 
assembly and doubler installations. The labor cost for the doubler 
installation is $6,000 per airplane and the doubler can be manufactured 
from local materials.

Regulatory Flexibility Determination and Analysis

    The Regulatory Flexibility Act of 1980 (RFA) was enacted by 
Congress to ensure that small entities are not unnecessarily or 
disproportionately burdened by government regulations. The RFA requires 
government agencies to determine whether rules would have a 
``significant economic impact on a substantial number of small 
entities,'' and, in cases where the rule would have an economic impact, 
the agency making the rule is obligated to conduct a Regulatory 
Flexibility Analysis in which alternatives to the rule are considered. 
FAA Order 2100.14A, Regulatory Flexibility Criteria and Guidance, 
outlines FAA procedures and criteria for complying with the RFA. Small 
entities are defined as small businesses, small not-for-profit 
organizations that are independently owned and operated, or airports 
operated by small governmental jurisdictions. A ``substantial number'' 
is defined as a number that is not less than 11 and that is more than 
one-third of the small entities subject to a proposed rule, or any 
number of small entities judged to be substantial by the rulemaking 
official. A ``significant economic impact'' is defined by an annualized 
net compliance cost, adjusted for inflation, which is greater than a 
threshold cost level for defined entity types.
    There are an estimated 240 Fairchild SA226 series airplanes in the 
U.S. registry that could be affected by the proposed action. For many 
of these airplanes, it is believed that the actions that are proposed 
have already been completed. The entities affected by the proposed AD 
are largely grouped in the

[[Page 31768]]

Standard Industrial Classification (SIC) 4512, Operators of Aircraft 
for Hire, classified as ``Unscheduled.'' FAA Order 2100.14A, Regulatory 
Flexibility Criteria and Guidance, defines a small entity in this 
classification as one that owns or operates nine or fewer aircraft.
    In order to experience a significant economic impact under Order 
2100.14A, an operator of aircraft for hire, unscheduled, would have to 
incur annualized costs of $4975 (1996 dollars) or more. Costs are 
estimated to be approximately $6,000 per airplane if only the doubler 
plates are installed, or as much as $10,933 per airplane if any ribs 
are found cracked and a rib assembly replacement is required, in 
addition to installing the doubler plate. Annualized costs are 
dependent on the required work, the cost of capital for airplane 
owners/operators, and the expected length of time that the required 
changes are expected to be in use. Since the changes are assumed to be 
permanent, the service life of the changes is the remaining life of the 
airplane. The cost of capital for the airplane owners/operators is 
assumed to be 15 percent. Under these conditions, no owner/operator of 
a single airplane would be subject to significant costs if the expected 
remaining service life of the aircraft were more than:
    (a) 1.43 years (approximately 17 months), if the doubler plate 
installation is required; or
    (b) 2.9 years (approximately 35 months) if both the doubler plate 
installation and rib replacement is required.
    Ownership of the new SA226 series airplanes (i.e.: the airplanes 
other than the older Model SA226TC) is very widely dispersed. There are 
five separate entities (excluding Swearingen) that show ownership of 
newer SA226 series airplanes in the U.S. Registry, each of which owns 
two SA226 series airplanes. According to the manufacturer, these 
airplanes are relatively new with typically less than 10,000 hours 
total time-in-service (TIS), and are employed primarily as corporate 
aircraft with usage rates at approximately 400 hours TIS per year. 
Allocating a nominal remaining service life of 25,000 hours total TIS 
(out of a total service life of 35,000 hours) at the rate of 500 hours 
TIS per year, suggests remaining lives on the order of 50 years. Even 
with a remaining service life of half of this, or 25 years, annualized 
costs for both doubler plate installation and rib replacement would be 
on the order of $1,715. Thus, an owner of two such airplanes would 
experience annualized costs for the proposed AD of approximately 
$3,430, which is a figure less than 70 percent of threshold value for 
significant cost.
    The manufacturer indicates that most of the older Fairchild Model 
SA226-TC airplanes (80 of which were listed in the U.S. Registry 
records), have probably been modified under the 1981 service bulletin 
that will be made mandatory by the AD. Fairchild Model SA226-TC 
airplanes in service have average cumulative usage of approximately 
25,000 to 30,000 hours total TIS, with a likely average annual usage in 
cargo service of 1,000 to 1,500 hours TIS, and an economic life of 
35,000 hours total TIS. This suggests that most Fairchild Model SA226-
TC airplanes have remaining lives of about five years (even without 
prospective modifications that are likely to extend the life of the 
aircraft). A five-year life for an airplane that would be required to 
carry out both modifications implies that annualized costs would be 
approximately $3,300. Thus, an owner of a single aging unmodified 
Fairchild Model SA226-TC airplane would not experience a significant 
economic impact.
    According to U.S. Registry records, there are 12 entities 
(excluding Sweringen) that own 2 or more Fairchild Model SA226-TC 
airplanes, accounting for a total of 49 airplanes. Because of the age 
of the aircraft and the likelihood of compliance with the original 
service bulletin (dated 1981), the FAA believes that significant 
impacts will not be felt by most owners of the these airplanes. In 
addition, the eight owners of two or more of these airplanes account 
for less than one-tenth of the affected entities. For these reasons, 
the FAA has determined that the proposed AD would not have a 
significant economic impact on a substantial number of small aircraft 
operators. The FAA solicits comments concerning the impact of this 
proposed AD on small entity owners of affected airplanes. Based on the 
possibility that this proposed AD could have a significant impact on a 
substantial number of small entities, the FAA conducted a regulatory 
flexibility analysis.
    A copy of the full Cost Analysis and Regulatory Flexibility 
Determination for the proposed action may be examined at the FAA, 
Central Region, Office of the Assistant Chief Counsel, Attention: Rules 
Docket No. 96-CE-58-AD, Room 1558, 601 E. 12th Street, Kansas City, 
Missouri.

FAA's Aging Commuter Aircraft Policy

    This action is consistent with the FAA's aging commuter airplane 
policy. This policy simply states that reliance on repetitive 
inspections of critical areas on airplanes utilized in commuter service 
carries an unnecessary safety risk when a design change exists that 
could eliminate or, in certain instances, reduce the number of those 
critical inspections. The alternative to installing the doubler or the 
new rib assembly would be relying on repetitive inspections to detect 
damaged wing ribs.

Regulatory Impact

    The regulations proposed herein would not have substantial direct 
effects on the States, on the relationship between the national 
government and the States, or on the distribution of power and 
responsibilities among the various levels of government. Therefore, in 
accordance with Executive Order 12612, it is determined that this 
proposal would not have sufficient federalism implications to warrant 
the preparation of a Federalism Assessment.
    For the reasons discussed above, I certify that this action (1) is 
not a ``significant regulatory action'' under Executive Order 12866; 
(2) is not a ``significant rule'' under DOT Regulatory Policies and 
Procedures (44 FR 11034, February 26, 1979); and (3) if promulgated, 
will not have a significant economic impact, positive or negative, on a 
substantial number of small entities under the criteria of the 
Regulatory Flexibility Act. A copy of the draft regulatory evaluation 
prepared for this action has been placed in the Rules Docket. A copy of 
it may be obtained by contacting the Rules Docket at the location 
provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration proposes to amend 
part 39 of the Federal Aviation Regulations (14 CFR part 39) as 
follows:

PART 39--AIRWORTHINESS DIRECTIVES

    1. The authority citation for part 39 continues to read as follows:

    Authority: 49 USC 106(g), 40113, 44701.

[[Page 31769]]

Sec. 39.13  [Amended]

    2. Section 39.13 is amended by adding a new airworthiness directive 
(AD) to read as follows:

Fairchild Aircraft Inc.: Docket No. 96-CE-58-AD.

    Applicability: The following Models and serial numbered 
airplanes, certificated in any category.

------------------------------------------------------------------------
                Models                             Serial Nos.          
------------------------------------------------------------------------
SA226-TC..............................  TC201 through TC379.            
SA226-T...............................  T201 through T275, and T277     
                                         through T291.                  
SA226-T(B)............................  T(B)275, and T(B)292 through    
                                         T(B)378.                       
SA226-AT..............................  AT001 through AT069.            
------------------------------------------------------------------------

    Note 1: This AD applies to each airplane identified in the 
preceding applicability provision, regardless of whether it has been 
modified, altered, or repaired in the area subject to the 
requirements of this AD. For airplanes that have been modified, 
altered, or repaired so that the performance of the requirements of 
this AD is affected, the owner/operator must request approval for an 
alternative method of compliance in accordance with paragraph (c) of 
this AD. The request should include an assessment of the effect of 
the modification, alteration, or repair on the unsafe condition 
addressed by this AD; and, if the unsafe condition has not been 
eliminated, the request should include specific proposed actions to 
address it.
    Compliance: Required within the next 500 hours time-in-service 
(TIS) after the effective date of this AD, unless already 
accomplished.

    Note 2: The compliance time of this AD takes precedence over the 
compliance time in the Fairchild Service Bulletin referenced below.

    To prevent asymmetrical flap deflection forcing the airplane 
into an uncommanded roll and cause loss of control of the airplane, 
accomplish the following:
    (a) Inspect both wing trailing edge ribs at the center flap 
actuator attach brackets, wing stations (WS) 98.385 and 100.635, for 
cracks in accordance with the Accomplishment Instructions section, 
Part A, of Fairchild Service Bulletin (SB) 57-016, Issued: June 25, 
1981; Revised: December 9, 1981.
    (1) If no cracks are found, prior to further flight, install the 
reinforcement doubler, part number (P/N) 27K36075-7 or an FAA 
approved, in accordance with the Accomplishment Instructions 
section, Part B of Fairchild SB 57-016, Issued: June 25, 1981; 
Revised: December 9, 1981.
    (2) If any cracks are found, prior to further flight, replace 
any cracked rib with a new rib assembly (P/N 27-31085-1/2 or 27-
31086-1/2 or an FAA-approved) and install the new reinforcement 
doubler (P/N 27K36075-7 or an FAA equivalent) in accordance with the 
Accomplishment Instructions section, Part B and Part C of Fairchild 
SB 57-016, Issued: June 25, 1981; Revised: December 9, 1981.
    (b) Special flight permits may be issued in accordance with 
sections 21.197 and 21.199 of the Federal Aviation Regulations (14 
CFR 21.197 and 21.199) to operate the airplane to a location where 
the requirements of this AD can be accomplished.
    (c) An alternative method of compliance or adjustment of 
compliance time that provides an equivalent level of safety may be 
approved by the Manager, Fort Worth Airplane Certification Office, 
2601 Meacham Boulevard, Fort Worth, Texas 76193-0150. The request 
shall be forwarded through an appropriate FAA Maintenance Inspector, 
who may add comments and then send it to the Manager, Fort Worth 
Airplane Certification Office.

    Note 3: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Fort Worth Airplane Certification Office.

    (d) All persons affected by this directive may obtain copies of 
the document referred to herein upon request to Fairchild Aircraft, 
Inc., P. O. Box 32486, San Antonio, Texas, 78284; or may examine 
this document at the FAA, Central Region, Office of the Assistant 
Chief Counsel, Room 1558, 601 E. 12th Street, Kansas City, Missouri 
64106.

    Issued in Kansas City, Missouri, on June 4, 1997.
John R. Colomy,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 97-15174 Filed 6-10-97; 8:45 am]
BILLING CODE 4910-13-U