Airworthiness Directives; DG Flugzeugbau GmbH, Model DG-500MB Sailplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Final rule.

SUMMARY:

The FAA adopts a new airworthiness directive (AD) for certain DG Flugzeugbau GmbH Model DG-500MB sailplanes. This AD requires you to replace the engine pylon extension/retraction Warner LA10 spindle drive with an improved designed Stross BSA 10 spindle drive and to modify the electrical system following applicable service information. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Germany. We are issuing this AD to prevent failure of the Warner LA10 spindle drive, which could result in failure of the engine pylon extension/retraction mechanism. This condition could cause an unstable engine pylon assembly during flight with loss of control of the sailplane.

DATES:

This AD becomes effective on October 22, 2004.

As of October 22, 2004, the Director of the Federal Register approved the incorporation by reference of certain publications listed in the regulation.

ADDRESSES:

You may get the service information identified in this AD from DG Flugzeugbau, Postbox 41 20, 76625 Bruchsal, Germany; telephone: 49 7257 890; facsimile: 49 7257 8922.

You may view the AD docket at FAA, Central Region, Office of the Regional Counsel, Attention: Rules Docket No. 2004-CE-06-AD, 901 Locust, Room 506, Kansas City, Missouri 64106. Office hours are 8 a.m. to 4 p.m., Monday through Friday, except Federal holidays.

FOR FURTHER INFORMATION CONTACT:

Gregory Davison, Aerospace Engineer, FAA, Small Airplane Directorate, ACE-112, Room 301, 901 Locust, Kansas City, Missouri 64106; telephone: 816-329-4130; facsimile: 816-329-4090.

SUPPLEMENTARY INFORMATION:

Discussion

What events have caused this AD? The Luftfahrt-Bundesamt (LBA), which is the airworthiness authority for Germany, recently notified FAA that an unsafe condition may exist on certain DG Flugzeugbau GmbH Model DG-500MB sailplanes, all serial numbers up to and including 5E220B15. The LBA reports two separate fatigue failures of the Warner LA10 spindle drive.

What is the potential impact if FAA took no action? Failure of the Warner LA10 spindle drive could result in the engine pylon not rising or lowering, which could cause an unstable engine pylon assembly during flight. Failure of the engine pylon assembly during flight could result in loss of control of the sailplane.

Has FAA taken any action to this point? We issued a proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an AD that would apply to certain DG Flugzeugbau GmbH Model DG-500MB sailplanes. This proposal was published in the Federal Register as a notice of proposed rulemaking (NPRM) on May 20, 2004 (69 FR 29106). The NPRM proposed to require you to replace the Warner LA10 spindle drive with the Stross BSA 10 spindle drive and to modify the electrical system following Technical Note No. 843/18, issue 2, dated June 25, 2003.

Comments

Was the public invited to comment? We provided the public the opportunity to participate in developing this AD. We received no comments on the proposal or on the determination of the cost to the public.

Conclusion

What is FAA's final determination on this issue? We have carefully reviewed the available data and determined that air safety and the public interest require adopting the AD as proposed except for minor editorial corrections. We have determined that these minor corrections:

—Are consistent with the intent that was proposed in the NPRM for correcting the unsafe condition; and

—Do not add any additional burden upon the public than was already proposed in the NPRM.

Changes to 14 CFR Part 39—Effect on the AD

How does the revision to 14 CFR part 39 affect this AD? On July 10, 2002, the FAA published a new version of 14 CFR part 39 (67 FR 47997, July 22, 2002), which governs the FAA's AD system. This regulation now includes material that relates to altered products, special flight permits, and alternative methods of compliance. This material previously was included in each individual AD. Since this material is included in 14 CFR part 39, we will not include it in future AD actions.

Costs of Compliance

How many sailplanes does this AD impact? We estimate that this AD affects 4 sailplanes in the U.S. registry.

What is the cost impact of this AD on owners/operators of the affected sailplanes? We estimate the following costs to accomplish the replacement and modification:

Regulatory Findings

Will this AD impact various entities? We have determined that this AD will not have federalism implications under Executive Order 13132. This AD will not have a substantial direct effect 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.

Will this AD involve a significant rule or regulatory action? For the reasons discussed above, I certify that this AD:

1. Is not a “significant regulatory action” under Executive Order 12866;

2. Is not a “significant rule” under the 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.

We prepared a summary of the costs to comply with this AD and placed it in the AD Docket. You may get a copy of this summary by sending a request to us at the address listed under ADDRESSES. Include “AD Docket No. 2004-CE-06-AD” in your request.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Incorporation by reference
• Safety

Adoption of the Amendment

Accordingly, under 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.

2. FAA amends § 39.13 by adding a new AD to read as follows:

2004-18-12 DG Flugzeugbau GmbH: Amendment 39-13790; Docket No. 2004-CE-06-AD.

When Does This AD Become Effective?

(a) This AD becomes effective on October 22, 2004.

What Other ADs Are Affected by This Action?

(b) None.

What Sailplanes Are Affected by This AD?

(c) This AD affects the following sailplane models and serial numbers that are certificated in any category: DG Flugzeugbau Model DG-500MB, all serial numbers up to and including 5E220B15.

What Is the Unsafe Condition Presented in This AD?

(d) This AD is the result of Warner LA10 spindle drive failure. The actions specified in this AD are intended to prevent failure of the Warner LA10 spindle drive, which could result in failure of the engine pylon extension/retraction mechanism. This condition could cause an unstable engine pylon assembly during flight with consequent loss of control of the sailplane.

What Must I Do To Address This Problem?

(e) To address this problem, you must do the following:

May I Request an Alternative Method of Compliance?

(f) You may request a different method of compliance or a different compliance time for this AD by following the procedures in 14 CFR 39.19. Unless FAA authorizes otherwise, send your request to your principal inspector. The principal inspector may add comments and will send your request to the Manager, Standards Office, Small Airplane Directorate, FAA. For information on any already approved alternative methods of compliance, contact Gregory Davison, Aerospace Engineer, FAA, Small Airplane Directorate, ACE-112, Room 301, 901 Locust, Kansas City, Missouri 64106; telephone: 816-329-4130; facsimile: 816-329-4090.

Does This AD Incorporate Any Material by Reference?

(g) You must do the actions required by this AD following the instructions in DG Flugzeugbau GmbH Technical Note No. 843/18 issue 2, dated June 25, 2003. The Director of the Federal Register approved the incorporation by reference of this service bulletin in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. You may get a copy from DG Flugzeugbau, Postbox 41 20, 76625 Bruchsal, Germany. You may review copies at FAA, Central Region, Office of the Regional Counsel, 901 Locust, Room 506, Kansas City, Missouri 64106; or at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call (202) 741-6030, or go to: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.

Is There Other Information That Relates to This Subject?

(h) LBA airworthiness directive 2003-409, dated December 9, 2003, and Technical Note No. 843/18, issue 2, dated June 25, 2003, also address the subject of this AD.