AD 2000-20-10

This amendment adopts a new airworthiness directive (AD) that applies to certain DG Flugzeugbau (DG Flugzeugbau) GmbH Model DG 800B sailplanes. This AD requires you to measure and correct improper propeller drive belt tension. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for the Federal Republic of Germany. The actions specified in this AD are intended to correct improper drive belt tension and consequent engine crankshaft or connecting rod bearing damage. Such damage could result in loss of propulsion during critical phases of flight.

Final rule

2000-20-10 DG FLUGZEUGBAU GMBH: Amendment 39-11921; Docket No. 99-CE-90-AD.

(a) What sailplanes are affected by this AD? Model DG-800B sailplanes, all serial numbers, that are:

(1) certificated in any category; and

(2) equipped with SOLO engines.

(b) Who must comply with this AD? Anyone who wishes to operate any of the above sailplanes on the U.S. Register must comply with this AD.

(c) What problem does this AD address? The actions specified by this AD are intended to correct improper drive belt tension and consequent engine crankshaft or connecting rod bearing damage. Such damage could result in loss of propulsion during critical phases of flight.

(d) What actions must I accomplish to address this problem? To address this problem, you must accomplish the following:

Actions
Compliance Times
Procedures

(1) Measure the drive belt tension. The difference should be a minimum of 6 millimeters (mm) (0.236 inches (in)) and should not exceed 11 mm (0.433 in).

Within the next 25 hours time-in-service (TIS) or 90 days after November 27, 2000, (the effective date of this AD), whichever comes first.

Follow the procedures in DG Flugzeugbau Technical Note (TN) 873/16, dated October 25, 1999, and the Maintenance Manual for DG-800B.
(2) If you find improper tension as specified in this AD, accomplish the following:

(i) Lower the tension if it is too high. Check the position of the propeller in relation to the engine compression point to assure it is within limits, and adjust if necessary.

Before operating the sailplane.

(ii) If you have to reduce the drive belt tension, execute a ground test run. Check to assure that the position of the propeller in relation to the engine compression point has not changed, and adjust as necessary. If this has happened, the drive belt has slipped due to too low tension.

(iii) Notify DG Flugzeugbau if tension problems are still not resolved.(e) Can I comply with this AD in any other way? You may use an alternative method of compliance or adjust the compliance time if:

(1) Your alternative method of compliance provides an equivalent level of safety; and

(2) The Manager, Small Airplane Directorate, approves your alternative. Submit your request through an FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Small Airplane Directorate.

Note 1: This AD applies to each sailplane identified in paragraph (a) of this AD, 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 you have not eliminated the unsafe condition, specific actions you propose to address it.

(f) Where can I get information about any already-approved alternative methods of compliance? Contact Mike Kiesov, Aerospace Engineer, FAA, Small Airplane Directorate, 901 Locust, Room 301, Kansas City, Missouri 64106; telephone: (816) 329-4144; facsimile: (816) 329-4090.

(g) What if I need to fly the sailplane to another location to comply with this AD? The FAA can issue a special flight permit under sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate your sailplane to a location where you can accomplish the requirements of this AD.

(h) Are any service bulletins incorporated into this AD by reference? Actions required by this AD must be done in accordance with DG Flugzeugbau Technical Note (TN) 873/16, dated October 25, 1999. The Director of the Federal Register approved this incorporation by reference under 5 U.S.C. 552(a) and 1 CFR part 51. You can get copies from DG Flugzeugbau, Postbox 41 20, D-76646 Bruchsal, Federal Republic of Germany; telephone: +49 7257-890; facsimile: +49 7257-8922. You can look at copies at the FAA, Central Region, Office of the Regional Counsel, 901 Locust, Room 506, Kansas City, Missouri, or at the Office of the Federal Register, 800 North Capitol Street, NW, suite 700, Washington, DC 20001.

Note 2: The subject of this AD is addressed in German AD Number 1999-377, dated December 2, 1999

(i) When does this amendment become effective? This amendment becomes effective on November 27, 2000.

Discussion
What events have caused this proposed AD? The Luftfahrt-Bundesamt (LBA), which is the airworthiness authority for the Federal Republic of Germany, recently notified the FAA that an unsafe condition may exist on all DG Flugzeugbau GmbH Model DG-800B sailplanes equipped with a SOLO engine. The LBA reports that 5 sailplanes had a broken crankshaft or connecting rod bearing failures. Improper drive belt tension caused the damage and failures.

What happens if you do not correct the condition? This condition, if not corrected, could result in loss of propulsion during critical phases of flight.

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 Model DG 800B sailplanes. This proposal was published in the Federal Register as a notice of proposed rulemaking (NPRM) on August 10, 2000 (65 FR 48931).The NPRM proposed to measure and correct improper propeller drive belt tension.

Was the public invited to comment? Interested persons were 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
What is FAA's Final Determination on this Issue? After careful review of all available information related to the subject presented above, we have determined that air safety and the public interest require the adoption of the rule as proposed except for minor editorial corrections. We 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.

What are the differences between the LBA AD and this AD? The German AD requires measuring the drive belt tension within the next 25 hours time-in-service but no later than December 31, 1999, on the affected sailplanes registered in Germany. We require measuring the drive belt tension within the next 25 hours time-in-service or 90 days after the effective date of this AD, whichever occurs first. Why is the compliance time in both hours time-in-service and calendar time? The unsafe condition described in this AD does not originate as a result of sailplane operation. Applying improper tension to the propeller belt drive can occur at any time. The condition worsens with sailplane operation, but could already exist now. The compliance times afford the following:

- the 25 hours TIS provides that the high-usage sailplanes are inspected for improper tension in a reasonable time period; and

- the 90 day compliance time provides that improper tension does not go undetected for a long period of time on low-usage sailplanes.

Cost Impact
How many sailplanes does this AD impact? We estimate that this AD affects 6 sailplanes in the U.S. registry. What is thecost impact of this AD on owners/operators of the affected sailplanes? We estimate the following costs to accomplish the measurement:

Labor Cost
Parts Cost
Total Cost Per Sailplane
Total Cost on U.S. Sailplane Operators
3 workhours X $60 per hour = $180.
Not applicable.
$180 per sailplane.
$180 X 6 = $1,080

Regulatory Impact
Does this AD impact various entities? The regulations adopted herein 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. Therefore, it is determined that this final rule does not have federalism implications under Executive Order 13132.

Does this AD involve a significant rule or regulatory action? 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, 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 Section 39.13 byadding a new AD to read as follows: