[Federal Register Volume 62, Number 49 (Thursday, March 13, 1997)]
[Rules and Regulations]
[Pages 11763-11764]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-6256]


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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 92-CE-25-AD; Amendment 39-9962; AD 97-06-05]
RIN 2120-AA64


Airworthiness Directives; Avions Pierre Robin Model R2160 
Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD) that 
applies to Avions Pierre Robin Model R2160 airplanes. This action 
requires repetitively inspecting the weld area between the strut and 
the lower plate of the nose landing gear leg for cracks, and replacing 
the strut when cracks are found. The AD is the result of several 
reports of cracks in the weld securing the nose wheel steering bottom 
bracket to the nose landing gear leg on the affected airplanes. The 
actions specified by this AD are intended to prevent nose landing gear 
failure caused by cracks in the weld area between the strut and the 
lower plate of the nose landing gear leg, which could result in loss of 
control of the airplane during landing operations.

DATES: Effective May 16, 1997.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of May 16, 1997.

ADDRESSES: Service information that applies to this AD may be obtained 
from Avions Pierre Robin, 1, Route de Troyes, 21121 Darois France; 
telephone: 80 35 61 01; facsimile: 80 35 60 80. This information may 
also be examined at the Federal Aviation Administration (FAA), Central 
Region, Office of the Assistant Chief Counsel, Attention: Rules Docket 
No. 92-CE-25-AD, Room 1558, 601 E. 12th Street, Kansas City, Missouri 
64106; or at the Office of the Federal Register, 800 North Capitol 
Street, NW., suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Mr. Greg Holt, Program Manager, 
Brussels Aircraft Certification Division, FAA, Europe, Africa, and 
Middle East Office, c/o American Embassy, B-1000 Brussels, Belgium; 
telephone (32 2) 513.2692; facsimile (32 2) 230.6899; or Mr. Roman T. 
Gabrys, Project Officer, Small Airplane Directorate, Aircraft 
Certification Office, FAA, 1201 Walnut, suite 900, Kansas City, 
Missouri 64106; telephone (816) 426-6934; facsimile (816) 426-2169.

SUPPLEMENTARY INFORMATION:

Events Leading to the Issuance of This AD

    A proposal to amend part 39 of the Federal Aviation Regulations (14 
CFR part 39) to include an AD that would apply to Avions Pierre Robin 
Model R2160 airplanes was published in the Federal Register as a notice 
of proposed rulemaking (NPRM) on November 13, 1996 (61 FR 58145). The 
NPRM proposed to require repetitively inspecting the weld area between 
the strut and the lower plate of the nose landing gear leg for cracks, 
and replacing the strut when cracks are found. Accomplishment of the 
proposed inspections as specified in the NPRM would be in accordance 
with Avions Pierre Robin Service Bulletin (SB) No. 101, Revision 3, 
dated March 5, 1992.
    The NPRM resulted from several reports of cracks in the weld 
securing the nose wheel steering bottom bracket to the nose landing 
gear leg on the affected airplanes.
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. No comments were received on the 
proposed AD or the FAA's determination of the cost to the public.

The FAA's Determination

    After careful review of all available information related to the 
subject presented above, the FAA has determined that air safety and the 
public interest require the adoption of the rule as proposed except for 
minor editorial corrections. The FAA has determined that these minor 
corrections will not change the meaning of the AD and will not add any 
additional burden upon the public than was already proposed.

Differences Between This AD, Service Bulletin, and DGAC AD

    Both Avions Pierre Robin SB No. 101, Revision 3, dated March 5, 
1992, and DGAC AD 83-206(A)R3, dated March 18, 1992, specify repetitive 
inspection intervals of 25 hours time-in-service if a crack in the weld 
area is found that is within a certain limit. The limit is ``if the 
crack runs along the circumference and is less than 15 mm long max. or/
and radial crack is less than 8 mm max.'' This AD does not allow 
continued flight if any crack is found. FAA policy is to disallow 
airplane operation when known cracks exist in primary structure, unless 
the abililty to sustain ultimate load with these cracks is proven. The 
nose landing gear leg is considered primary structure, and the FAA has 
not received any analysis to prove that ultimate load can be sustained 
with cracks in this area.

Cost Impact

    The FAA estimates that 10 airplanes in the U.S. registry will be 
affected by this AD, that it will take approximately 1 workhour per 
airplane to accomplish the initial inspection, and that the average 
labor rate is approximately $60 an hour. Based on these figures, the 
total cost impact of the AD on U.S. operators is estimated to be $600. 
This figure does not take into account the number of repetitive 
inspections each airplane owner/operator will incur over the life of 
the airplane, or the number of airplanes that could have cracked weld 
areas and would need the strut replaced. The FAA has no way of 
determining the number of repetitive inspections each owner/operator 
would incur over the life of the airplane or the number of nose landing 
gear leg struts that could need to be replaced because of cracks in the 
weld area.

Regulatory Impact

    The regulations adopted herein will not have substantial direct 
effects on the States, on the relationship between the

[[Page 11764]]

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 final 
rule does 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) 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 final evaluation prepared for this 
action is contained 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, Incorporation by 
reference, Safety.

Adoption of the Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration amends 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.


Sec. 39.13  [Amended]

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

97-06-05  Avions Pierre Robin: Amendment 39-9962; Docket No. 92-CE-
25-AD.

    Applicability: Model R2160 airplanes (all serial numbers), 
certificated in any category.

    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 (d) 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 initially within the next 100 hours time-
in-service (TIS) after the effective date of this AD, unless already 
accomplished, and thereafter as follows, as applicable:
    1. If the width of the lower plate of the bottom bracket of the 
nose landing gear leg is 84 millimeters: at intervals not to exceed 
500 hours TIS; or
    2. If the width of the lower plate of the bottom bracket of the 
nose landing gear leg is less than 84 millimeters: at intervals not 
to exceed 100 hours TIS.
    To prevent nose landing gear failure caused by cracks in the 
weld area between the strut and the lower plate of the nose landing 
gear leg, which could result in loss of control of the airplane 
during landing operations, accomplish the following:
    (a) Inspect, using dye penetrant methods, the weld area between 
the strut and the lower plate of the nose landing gear leg for 
cracks in accordance with Avions Pierre Robin Service Bulletin (SB) 
No. 101, Revision 3, dated March 5, 1992.
    (b) If any crack is found during any inspection required by this 
AD, prior to further flight, replace the strut with a new or 
serviceable strut.
    (1) If the replacement strut is not new, prior to further flight 
after installing the strut, accomplish the inspection specified in 
paragraph (a) of this AD.
    (2) Replacing the strut with a new or serviceable strut does not 
eliminate the repetitive inspection requirement of this AD.
    (c) 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.
    (d) An alternative method of compliance or adjustment of the 
initial or repetitive compliance times that provides an equivalent 
level of safety may be approved by the Manager, Brussels Aircraft 
Certification Division, FAA, Europe, Africa, and Middle East Office, 
c/o American Embassy, B-1000 Brussels, Belgium. The request shall be 
forwarded through an appropriate FAA Maintenance Inspector, who may 
add comments and then send it to the Manager, Brussels Aircraft 
Certification Division.

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Brussels Aircraft Certification Division.

    (e) The inspection required by this AD shall be done in 
accordance with Avions Pierre Robin Service Bulletin No. 101, 
Revision 3, dated March 5, 1992. This incorporation by reference was 
approved by the Director of the Federal Register in accordance with 
5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from 
Avions Pierre Robin, 1, Route de Troyes, 21121 Darois France. Copies 
may be inspected at the FAA, Central Region, Office of the Assistant 
Chief Counsel, Room 1558, 601 E. 12th Street, Kansas City, Missouri, 
or at the Office of the Federal Register, 800 North Capitol Street, 
NW., suite 700, Washington, DC.
    (f) This amendment (39-9962) becomes effective on May 16, 1997.

    Issued in Kansas City, Missouri, on March 6, 1997.
Michael Gallagher,
Manager, Small Airplane Directorate, Aircraft Certification Service.
[FR Doc. 97-6256 Filed 3-12-97; 8:45 am]
BILLING CODE 4910-13-P