AD 2004-08-12

The FAA adopts a new airworthiness directive (AD) for all Schempp-Hirth Flugzeugbau GmbH (Schempp-Hirth) Models Ventus-2a, Ventus-2b, Discus-2a, and Discus-2b sailplanes. This AD requires you to inspect and modify the elevator mass balance. For Models Discus-2a and Discus-2b sailplanes only, this AD also requires you to replace the elevator pushrod. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Germany. We are issuing this AD to detect and correct problems within the sailplane elevator control system before they lead to flutter and sailplane instability. This could eventually result in loss of sailplane control.

Final rule.

2004-08-12 Schempp-Hirth Flugzeugbau Gmbh: Amendment 39-13581; Docket No. 2003-CE-59-AD.

When Does This AD Become Effective?

(a) This AD becomes effective on June 4, 2004.

What Other ADs Are Affected by This Action?

(b) None.

What Sailplanes Are Affected by This AD?

(c) This AD affects the following model and serial number sailplanes that are certificated in any category:

Group
Models
Serial Nos.

(1) Group 1 Sailplanes
Discus-2a and Discus-2b sailplanes that do not have Shempp-Hirth Technical Note No. 360-16 incorporated.

13 through 22, 24, 27, 30 through 48, 50, 51, 53, 54, 55, 57 through 63, 65, 67, 68, 71 through 79, 81, and 82.

(2) Group 2 Sailplanes
Ventus-2a, Ventus-2b, Discus-2a, and Discus 2b sailplanes.
Ventus-2a and Ventus-2b: 1, 2, 31, 32, 48, 54, 71, 117, 124 through 151, and 153; and all serial numbers that incorporate Modification Bulletin 349-42 or are equipped with a new tail unit per Shempp-HirthTechnical Note No. 349-27. Discus-2a and Discus-2b:
1 through 185, 187, 188, and 189.

What Is the Unsafe Condition Presented in This AD?

(d) This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Germany. The actions of this AD are intended to detect and correct problems within the sailplane elevator control system before they lead to flutter and sailplane instability. This could eventually result in loss of sailplane control.

What Must I Do To Address This Problem?

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

Actions
Compliance
Procedures
(1) For Group 1 sailplanes: Add a mass balance to the elevators and install an elevator pushrod in the vertical fin.
Within the next 25 hours time-in-service (TIS) after June 4, 2004 (the effective date of this AD), unless already done.
Follow Schempp-Hirth Technical Note No. 360-19, dated December 20, 2002 (LBA-approved January 18, 2003).
(2) For Group 2 sailplanes: Modify the mass balance weights.
Within the next 25 hours TIS after June 4, 2004 (the effective date of this AD), unless already done.
Follow Schempp-Hirth Technical Note No. 349-28, No. 360-20, and No. 863-8 (including appendix), dated September 16, 2003 (LBA-approved September 23, 2003).

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 Greg Davison, Aerospace Engineer, FAA, Small Airplane Directorate, 901 Locust, Room 301, 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 Schempp-Hirth Technical Note No. 360-19, dated December 20, 2002 (LBA-approved January 18, 2003); and Schempp-Hirth Technical Note No. 349-28, No. 360-20, and No. 863-8 (including appendix), dated September 16, 2003 (LBA-approved September 23, 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 Schempp-Hirth Flugzeugbau GmbH, Postfach 14 43, D-73230 Kirchheim/ Teck, Germany; telephone: 011 49 7021 7298-0; facsimile: 011 49 7021 7298-199. You may review copies at FAA, Central Region, Office of the Regional Counsel, 901 Locust, Room 506, Kansas City, Missouri 64106; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

Is There Other Information That Relates to This Subject?

(h) German AD No. 2003-048, effective date: March 6, 2003, and German AD No. 2003-280, effective date: October 2, 2003, also address the subject of this AD.

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 Schempp-Hirth Models Ventus-2a, Ventus-2b, Discus-2a, and Discus-2b sailplanes. The LBA reports that the potential exists for elevator mass balance problems on the referenced sailplanes.

What is the potential impact if FAA took no action? Elevator mass balance problems, if not detected and corrected, could lead to flutter and sailplane instability. This could eventually result in loss of sailplane control.

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 all Schempp-Hirth Flugzeugbau GmbH (Schempp-
Hirth) Models Ventus-2a, Ventus-2b, Discus-2a, and Discuss-2b sailplanes. This proposal was published in the Federal Register as a notice of proposed rulemaking (NPRM) on February 17, 2004 (69 FR 7380). The NPRM proposed to require you to inspect and modify the elevator mass balance. For Models Discus-2a and Discus-2b sailplanes only, this proposed AD would also require you to replace the elevator pushrod.

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 14CFR 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 the actions specified in Schempp-Hirth Technical Note No. 360-19 would affect 15 sailplanes in the U.S. registry and the actions specified in Schempp-Hirth Technical Note No. 349-28 would affect 51 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 following actions:

Affected technical note
Labor cost
Parts cost
Total cost per sailplane
Total cost U.S. operators
No. 360-19.
17 workhours at $65 per hour = $1,105
$135 per sailplane
$1,240
$18,600
No. 349-28
4 workhours at $65 per hour = $260
No cost for parts
260
13,260

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. 2003-CE-59-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.

39.13 [Amended]

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