AD 98-09-24

This amendment adopts a new airworthiness directive (AD) that applies to certain Diamond Aircraft Industries (Diamond) Models H-36 "Dimona" ; and HK 36 R "Super Dimona" sailplanes. This AD requires: inspecting the elevator rib area for damage on certain Models H-36 " Dimona" and HK 36 R "Super Dimona" sailplanes, and either immediately or eventually replacing the elevator ribs depending on the results of the inspection; replacing the M6 screws that attach the wheel axle to steel support with M8 screws on certain Models HK 36 R "Super Dimona" sailplanes; and inspecting the shoulder harness fittings for improper bonding on certain Diamond Model H-36 "Dimona" sailplanes, and repairing any harness with an improper bond. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Austria. The actions specified by this AD are intended to prevent failure of either the shoulder harness fittings, elevator rib, or the wheel axle to steel support attachment, which could result in passenger injury caused by an inadequate restraint system; reduced sailplane controllability caused by structural damage to the elevator; and/or reduced sailplane controllability during takeoff, landing, and ground operations caused by the installation of incorrect wheel axle screws.

Final rule

98-09-24 DIAMOND AIRCRAFT INDUSTRIES: Amendment 39-10505; Docket No. 97-CE-134-AD.
Applicability: The following sailplane models and serial numbers, certificated in any category:

Model H-36 "Dimona" sailplanes, all serial numbers; and
Model H 36 R "Super Dimona" sailplanes, serial numbers 36301 through 36414.

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 (e) 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 this AD, unless already accomplished.

To prevent failure of either the shoulder harness fittings, elevator rib, or the wheel axle to steel support attachment, which could result in passenger injury caused by an inadequate restraint system; reduced sailplane controllability caused by structural damage to the elevator; and/or reduced sailplane controllability during takeoff, landing, and ground operations caused by the installation of incorrect wheel axle screws, accomplish the following:

(a) Within the next 3 calendar months after the effective date of this AD, accomplish the following:

(1) For the Model H-36 "Dimona" sailplanes, all serial numbers; and the Model HK 36 R "Super Dimona" sailplanes, serial numbers 36301 through 36414, inspect the elevator rib area for damage. Accomplish this inspection in accordance with Diamond Work Instruction No.21, dated March 20, 1996, as referenced in Diamond Service Bulletin No. 51, dated March 30, 1996.

(2) For the Model HK 36 R "Super Dimona" sailplanes, serial numbers 36301 through 36327, replace the M6 screws that attach the wheel axle to steel support with M8 screws. Accomplish this replacement in accordance with Hoffman Work Instruction No. 10, dated May 29, 1991, as referenced in Hoffman Service Bulletin No. 27, dated May 31, 1991.

(3) For the Model H-36 "Dimona" sailplanes, serial numbers 3501 through 3539 and 3601 through 36143, inspect the shoulder harness fittings for improper bonding. Accomplish this inspection in accordance with Hoffman Service Bulletin 17, dated January 20, 1987.

(b) Prior to further flight after the inspections required by paragraphs (a)(1) and (a)(3) of this AD, accomplish the following:

(1) If any damage is found in the elevator rib area on any sailplane affected by paragraph (a)(1) of this AD, replace the elevator ribs in accordance with Diamond Work Instruction No. 21, dated March 20, 1996, as referenced in Diamond Service Bulletin No. 51, dated March 30, 1996.

(2) If an improper bonding is found on the shoulder harness fittings on any sailplane affected by paragraph (a)(3) of this AD, repair the shoulder harness fittings in accordance with Hoffman Service Bulletin 17, dated January 20, 1987.

(c) For the Model H-36 "Dimona" sailplanes, all serial numbers; and the Model HK 36 R "Super Dimona" sailplanes, serial numbers 36301 through 36414, within the next 3,000 hours time-in-service (TIS) after the effective date of this AD, replace the elevator ribs, unless already accomplished as required by paragraph (b)(1) of this AD. Accomplish this replacement in accordance with Diamond Work Instruction No. 21, dated March 20, 1996, as referenced in Diamond Service Bulletin No. 51, dated March 30, 1996.

(d) 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.

(e) An alternative method of compliance or adjustment of the 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 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Small Airplane Directorate.

(f) Questions or technical information related to the service information referenced in this AD should be
directed to Diamond Aircraft Industries, G.m.b.H., N.A. Otto-Strabe 5, A-2700, Wiener Neustadt, Austria. 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.

(g) The inspections, replacements, and repair required by this AD shall be done in accordance with Diamond Work Instruction No. 21, dated March 20, 1996, as referenced in Diamond Service Bulletin No. 51, dated March 30, 1996; Hoffman Work Instruction No. 10, dated May 29, 1991, as referenced in Hoffman Service Bulletin No. 27, dated May 31, 1991; and Hoffman Service Bulletin 17, dated January 20, 1987. 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 Diamond Aircraft Industries, G.m.b.H., N.A. Otto- Strabe 5, A-2700, Wiener Neustadt, Austria. 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 3: The subject of this AD is addressed in Austrian AD No. 85, dated May 29, 1996, for the elevator condition; Austrian AD No. 63, not dated, for the wheel axle screws condition; and Austrian AD No. 54, not dated, for the shoulder harness fittings condition.

(h) This amendment becomes effective on June 15, 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 Diamond Models H-36 " Dimona", and HK 36 R "Super Dimona" sailplanes was published in the Federal Register as a notice of proposed rulemaking (NPRM) on February 13, 1998 (63 FR 7324). The NPRM proposed to require inspecting the elevator rib area for damage on certain Models H-36 "Dimona" and HK 36 R "Super Dimona" sailplanes, and either immediately or eventually replacing the elevator ribs depending on the results of the inspection; replacing the M6 screws that attach the wheel axle to steel support with M8 screws on all of the affected airplanes; and inspecting the shoulder harness fittings for improper bonding on certain Diamond Model H-36 "Dimona" sailplanes, and repairing any harness with an improper bond. Accomplishment of the proposed actions as specified in the NPRM would be in accordance with Diamond Work Instruction No. 21, dated March 20, 1996, as referenced in Diamond Service Bulletin No. 51, dated March 30, 1996; Hoffman Work Instruction No. 10, dated May 29, 1991, as referenced in Hoffman Service Bulletin No. 27, dated May 31, 1991; and Hoffman Service Bulletin 17, dated January 20, 1987.

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

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 inadvertently included the Model H-36 "Dimona" sailplanes in the wheel to axle support screw replacement requirement of the NPRM. This requirement should only apply to certain Model HK 36 R "Super Dimona" airplanes. The final rule has been changed accordingly.

The FAA's DeterminationAfter 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 the applicability change in the wheel to axle support screw replacement requirement and minor editorial corrections. The FAA has determined that this change and the minor corrections will not add any additional burden upon the public than was already proposed.

Cost Impact
The FAA estimates that 15 sailplanes in the U.S. registry will be affected by the elevator portion of this AD, that it will take approximately 10 workhours per sailplane to accomplish the elevator portion of this AD, and that the average labor rate is approximately $60 an hour. Kits cost approximately $100 per sailplane. Based on these figures, the total cost impact of the elevator portion of this AD on U.S. operators is estimated to be $10,500, or $700 per sailplane.

The FAA estimates that 2 sailplanes in the U.S. registry will be affected by the wheel axle screws portion of this AD, that it will take approximately 6 workhours per sailplane to accomplish the wheel axle screws portion of this AD, and that the average labor rate is approximately $60 an hour. Kits cost approximately $165 per sailplane. Based on these figures, the total cost impact of the wheel axle screws portion of this AD on U.S. operators is estimated to be $1,050, or $525 per sailplane.

The FAA estimates that 8 sailplanes in the U.S. registry will be affected by the shoulder harness fittings portion of this AD, that it will take approximately 6 workhours per sailplane to accomplish the shoulder harness fittings portion of this action, and that the average labor rate is approximately $60 an hour. Parts cost approximately $10 per sailplane. Based on these figures, the total cost impact of the shoulder harness fittings portion of this AD on U.S. operators is estimated to be $2,960, or$370 per sailplane.

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: