AD 97-24-09

This amendment adopts a new airworthiness directive (AD) that applies to Burkhart Grob, Luft-und Raumfahrt (Grob), Model G 103 C Twin III SL sailplanes. This action requires repetitively inspecting the propeller bearing and upper pulley wheel for increased play and, if increased play is found, modifying the propeller bearing and pulley wheel with a part of improved design. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Germany. The actions specified by this AD are intended to prevent the loss of the sailplane engine propeller and possible loss of the sailplane.

Final rule

97-24-09 BURKHART GROB, LUFT-UND RAUMFAHRT: Amendment 39-10216; Docket No. 96-CE-37-AD.

Applicability: Model G 103 C Twin III SL Sailplanes (serial numbers 35002 through 35051), certificated in any category.

NOTE 1: This AD applies to each sailplane 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 sailplanes 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.

NOTE 2: The paragraph structure of this AD is as follows:

Level 1: (a), (b), (c), etc.
Level 2: (1), (2), (3), etc.
Level 3: (i), (ii), (iii), etc.

Level 2 and Level 3 structures are designations of the Level 1 paragraph they immediately follow.

Compliance: Required as indicated in the body of this AD, unless already accomplished.

To prevent the loss of the sailplane engine propeller and possible loss of the sailplane, accomplish the following:

(a) Within the next 5 engine operating hours after the effective date of this AD, do one of the following:

(1) Modify the propeller bearing and upper pulley wheel by installing parts of improved design in accordance with the "Actions: 2." and the "Installation Instructions" sections of Grob service bulletin (SB) 869-18, dated March 7, 1996, and Grob SB 869-18/2, dated July 8, 1996; or,

(2) Inspect the propeller bearing and upper pulley wheel for increased play (movement that exceeds or is equal to 0.4 mm) in accordance with the"Actions" section of Grob service bulletin (SB) 869-18, dated March 7, 1996.

(i) If increased play is found, prior to further flight, accomplish the modification in paragraph (a)(1) of this AD or,

(ii) If no increased play is found, continue to repetitively inspect for increased play in the propeller bearing and upper pulley wheel every 5 engine operating hours in accordance with the "Actions: 1." section in Grob SB 869-18, dated March 7, 1996, and Grob SB 869-18/2, dated July 8, 1996. If increased play is found during any inspection, then, prior to further flight, accomplish the modification in paragraph (a)(1) of this AD.

(b) Accomplishing the modification in paragraph (a)(1) of this AD is a terminating action to the repetitive inspection required in paragraph (a)(2)(ii) of this AD. This modification may be accomplished at any time, but must be accomplished if increased play is found.

(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 sailplane 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, Small Airplane Directorate, Airplane Certification Service, 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.

(e) The inspections and modifications required by this AD shall be done in accordance with Burkhart Grob, Luft-und Raumfahrt Service Bulletin 869-18, dated March 7, 1996, and Burkhart Grob, Luft-und Raumfahrt Service Bulletin 869-18/2, dated July 8, 1996, which is a revised page six of the Burkhart Grob, Luft-und Raumfahrt Service Bulletin 869-18, dated March 7, 1996. 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 Burkhart Grob Luft-und Raumfahrt, D-86874 Mattsies, Germany. 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 addresses German AD 96-206, April 4, 1996.

(f) This amendment (39-10216 ) becomes effective on January 5, 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 Grob Model G 103 C Twin III SL sailplanes was published in the Federal Register on January 29, 1997 (62 FR 4205). The action proposed to require inspecting the propeller bearing and pulley wheel for increased play, if there is no increased play in the propeller bearing and pulley wheel, continuing to inspect, and if increased play is found, modifying the propeller bearing and upper pulley wheel by installing a part of improved design. The modification would be considered a terminating action to the repetitive inspections. Accomplishment of this action would be in accordance with Grob Service Bulletin (SB) 869-18, dated March 7, 1996, and Grob SB 869-18/2, dated July 8, 1996, which is a revised page 6 of the Grob SB 869-18, dated March 7, 1996.

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 8 sailplanes in the U.S. registry will be affected by this AD, that it will take approximately 1 workhour per sailplane 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 $480 or $60 per sailplane.
Grob has informed the FAA that parts have been distributed to equip 7 of the 8 sailplanes in the United States, which would reduce the estimated impact on U.S. operators from $480 to $60.

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 ornegative, 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.

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