AD 98-18-13

This amendment adopts a new airworthiness directive (AD) that applies to certain SOCATA-Groupe AEROSPATIALE (Socata) Models TB20 and TB21 airplanes. This AD requires repetitively inspecting the main landing gear (MLG) attachment bearing (using a dye penetrant method) for cracks, and if cracks are found, replacing the bearing. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for France. The actions specified by this AD are intended to detect and correct cracks in the MLG attachment bearing, which could result in collapse of the main landing gear during taxi and landing operations.

Final rule.

98-18-13 SOCATA - GROUPE AEROSPATIALE: Amendment 39-10729; Docket No. 95-CE-64-AD.

Applicability: Models TB20 and TB21 airplanes, serial numbers 1 through 9999, 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 (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 as indicated in the body of thisAD, unless already accomplished.

To detect and correct cracks in the main landing gear (MLG) attachment bearing, which could result in collapse of the MLG during taxi and landing operations, accomplish the following:

NOTE 2: The compliance times of this AD are presented in landings instead of hours time-in-service (TIS). If the number of landings is unknown, hours TIS may be used by multiplying the number of hours TIS by 1.5.

(a) Upon the accumulation of 6,000 landings, upon the accumulation of 4,000 hours total TIS, or within the next 100 hours TIS after the effective date of this AD, whichever occurs later, inspect (with a dye penetrant method) the main landing gear (MLG) attachment bearing for cracks in accordance with the Accomplishment Instructions in SOCATA Service Bulletin (SB) No. SB 10-080 57, Amdt. 2, dated November 1995;

(1) If no cracks are found, continue to inspect the MLG attachment bearing for cracks at intervals not to exceed 1,500 landings or 1,000 hours TIS, whichever occurs later, until cracks are found, in accordance with the Accomplishment Instructions in the SOCATA SB No. SB 10-080 57, Amdt. 2, dated November 1995;

(2) If cracks are found in the MLG attachment bearing during any inspection required by this AD, prior to further flight, replace the MLG attachment bearing in accordance with the Accomplishment Instructions in the SOCATA SB No. SB 10-080 57, Amdt. 2, dated November 1995; and,

(3) Upon the accumulation of 6,000 landings or 4,000 hours TIS after the date of any MLG attachment bearing replacement, whichever occurs later, and thereafter at intervals not to exceed 1,500 landings or 1,000 hours TIS, inspect the MLG attachment bearing for cracks as specified in paragraph (a) of this AD.

(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 the initial or repetitive compliance times that provides an equivalent level of safety may be approved by the Manager, Small Airplane Directorate, FAA, 1201 Walnut, suite 900, Kansas City, Missouri 64106. The request shall be forwarded through an appropriate FAA Maintenance Inspector, who may add comments and then send it to the Manager, Small Airplane Directorate.

NOTE 3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Small Airplane Directorate.

(d) Questions or technical information related to Socata Service Bulletin No. SB 10-080 57, Amdt. 2, dated November 1995, should be directed the SOCATA - Groupe AEROSPATIALE, Socata Product Support, Aerodrome Tarbes-Ossun-Lourdes, B P 930-F65009 Tarbes Cedex, France; telephone: 33.5.62.41.76.52; facsimile: 33.5.62.41.76.54; or the Product Support Manager, SOCATA- Groupe AEROSPATIALE, North Perry Airport, 7501 Pembroke Road, Pembroke Pines, Florida 33023; telephone: (954) 893-1160; facsimile: (954) 964-4141. This service information may be examined at the FAA, Central Region, Office of the Regional Counsel, Room 1558, 601 E. 12th Street, Kansas City, Missouri 64106.

(e) The inspections and replacement required by this AD shall be done in accordance with Socata Service Bulletin No. SB 10-080 57, Amdt. 2, dated November 1995. 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 SOCATA-Groupe AEROSPATIALE, Tarbes-Ossun-Lourdes, B P 930, 65009 Tarbes Cedex, France, or the Product Support Manager, SOCATA-Groupe AEROSPATIALE, North Perry Airport, 7501 Pembroke Road, Pembroke Pines, Florida 33023. Copies may be inspected at the FAA, Central Region, Office of the Regional 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.

NOTE 4: The subject of this AD is addressed in French AD 94-266(A)R2, dated December 6, 1995.

(f) This amendment becomes effective on October 24, 1998.

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 certain Socata Models TB20 and TB21 airplanes was published in the Federal Register as a notice of proposed rulemaking (NPRM) on June 26, 1998 (63 FR 34830). The NPRM proposed to require repetitively inspecting (using a dye penetrant method) for cracks on the MLG attachment bearing. If cracks are found, the NPRM proposed to require replacing the cracked attachment bearing. Accomplishment of the proposed actions as specified in the NPRM would be in accordance with Socata Service Bulletin No. SB 10-080 57, Amdt. 2, dated November 1995.

The NPRM was the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for France.

Interested persons have been afforded an opportunity to participate in the making of this amendment. No comments were received on the proposed rule 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.

Cost Impact
The FAA estimates that 199 airplanes in the U.S. registry will be affected by this AD.

Accomplishing the inspection will take approximately 4 workhours per airplane, and the average labor rate is approximately $60 an hour. Based on these figures, the total cost impact of the inspection on U.S. operators is estimated to be $47,760, or $240 per airplane.

The replacement will take approximately 1 workhour to replace the bearing, if necessary, at anaverage labor rate of $60 per hour. Parts cost approximately $800 per airplane. Based on these figures, the total cost impact of the modification on U.S. operators is estimated to be $171,140, or $860 per airplane.

The FAA has no way to determine the number of repetitive inspections that will be incurred over the life of the airplane.

Regulatory Impact
The regulations adopted herein will 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 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 U.S.C. 106(g), 40113, 44701.

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