00-20251. Airworthiness Directives; DG Flugzeugbau GmbH Model DG-800B Sailplanes

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

This document proposes to adopt a new airworthiness directive (AD) that would apply to certain DG Flugzeugbau (DG Flugzeugbau) GmbH Model DG 800B sailplanes. The proposed AD would require you to measure and correct improper propeller drive belt tension. The proposed 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 the proposed 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.

DATES:

The Federal Aviation Administration (FAA) must receive any comments on this proposed rule on or before September 11, 2000.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Central Region, Office of the Regional Counsel, Attention: Rules Docket No. 99-CE-90-AD, 901 Locust, Room 506, Kansas City, Missouri 64106. You may inspect comments at this location between 8 a.m. and 4 p.m., Monday through Friday, except holidays.

Service information that applies to the proposed AD may be obtained from DG Flugzeugbau, Postbox 41 20, D-76646 Bruchsal, Federal Republic of Germany; telephone: [phone]; facsimile: [phone]. You may examine this information at the Rules Docket at the address above.

FOR FURTHER INFORMATION CONTACT:

Mike Kiesov, Aerospace Engineer, FAA, Small Airplane Directorate, 901 Locust, Room 301, Kansas City, Missouri 64016; telephone: [phone]; facsimile: [phone].

SUPPLEMENTARY INFORMATION:

Comments Invited

How Do I Comment on This AD?

We invite your comments on the proposed rule. You may submit whatever written data, views, or arguments you choose. You need to include the rule's docket number and submit your comments in triplicate to the address specified under the caption ADDRESSES. We will consider all comments received on or before the closing date specified above, before acting on the proposed rule. We may change the proposals contained in this notice in light of the comments received.

Are There Any Specific Portions of the AD I Should Pay Attention to?

The FAA specifically invites comments on the overall regulatory, economic, environmental, and energy aspects of the proposed rule that might necessitate a need to modify the proposed rule. You may examine all comments we receive. We will file a report in the Rules Docket that summarizes each FAA contact with the public that concerns the substantive parts of this proposal.

The FAA is reexamining the writing style we currently use in regulatory documents, in response to the Presidential memorandum of June 1, 1998. That memorandum requires federal agencies to communicate more clearly with the public. We are interested in your comments on the ease of understanding this document, and any other suggestions you might have to improve the clarity of FAA communications that affect you. You can get more information about the Presidential memorandum and the plain language initiative at http://www.faa.gov/​language/​.

How Can I Be Sure FAA Receives My Comment?

If you want us to acknowledge the receipt of your comments, you must include a self-addressed, stamped postcard. On the postcard, write “Comments to Docket No. 99-CE-90-AD.” We will date stamp and mail the postcard back to you.

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.

Relevant Service Information

Is There Service Information That Applies to This Subject?

DG Flugzeugbau has issued Technical Note (TN) 873/16, dated October 25, 1999.

What Are the Provisions of This Service Bulletin?

The service bulletin describes procedures for measuring drive belt tension, and specifies where you can obtain procedures for correcting improper tension.

What Actions Did LBA Take?

The LBA issued German AD Number 1999-377, dated December 2, 1999, referencing DG Flugzeugbau TN 873/16, in order to assure the continued airworthiness of these sailplanes in Germany.

Was This in Accordance With the Bilateral Airworthiness Agreement?

DG Flugzeugbau manufactured this sailplane model in Germany. The FAA type certificated the sailplane model for operation in the United States under the provisions of section 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the applicable bilateral airworthiness agreement. Complying with this bilateral airworthiness agreement, the LBA informed the FAA of the situation described above.

The FAA's Determination and an Explanation of the Provisions of the Proposed AD

What Has FAA Decided?

The FAA has examined the findings of the LBA; reviewed all available information, including the service information referenced above, and determined that:

—the unsafe condition referenced in this document exists or could develop on other DG Flugzeugbau GmbH Model DG-800B sailplanes of the same type design that are equipped with SOLO engines;

—these sailplanes should have the actions specified in the above service bulletin incorporated; and

—the FAA should take AD action to correct this unsafe condition.

What Does This Proposed AD Require?

This proposed AD requires you to measure and correct improper propeller drive belt tension.

What Are the Differences Between the LBA AD and the Proposed AD?

The German AD requires measuring the drive belt tension within the next 25 hour time-in-service but no later than December 31, 1999, on the affected sailplanes registered in Germany. We propose a requirement that you measure drive belt tension within the next 25 hours time-in-service or 90 days after the effective date of the proposed 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

This Proposed AD Impacts How Many Sailplanes?

We estimate that the proposed AD would affect 6 sailplanes in the U.S. registry.

What Is the Cost Impact of the Proposed Measurement for the Affected Sailplanes on the U.S. Register?

We estimate that it would take approximately 3 workhours per sailplane to accomplish the proposed measurement, at an average labor rate of $60 an hour. Based on the cost factors presented above, we estimate the total cost impact of the proposed measurement on U.S. operators to be $180 per sailplane.

Regulatory Impact

How Does This AD Impact Relations Between Federal and State Governments?

The proposed regulations would 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. We have determined that this proposed rule would not have federalism implications under Executive Order 13132.

How 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 Department of Transportation Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) if put into effect, 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 have placed a copy of the draft regulatory evaluation prepared for this action in the Rules Docket. You may obtain a copy of it 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
• Safety

The Proposed Amendment

Accordingly, under the authority delegated to me by the Administrator, the Federal Aviation Administration proposes to amend 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 by adding a new airworthiness directive (AD) to read as follows:

DG Flugzeugbau GMBH: 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? Our intent is that the actions specified in the AD 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 must I do to address this problem? To address this problem, you must accomplish the following actions:

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 or 90 days after the effective date of the 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 (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	Before operating the sailplane.

(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, 901 Locust, Room 301, Kansas City, Missouri 64106.

Note:

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. You should include in the request 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? You can contact Mike Kiesov, Aerospace Engineer, FAA, Small Airplane Directorate, 901 Locust, Room 301, Kansas City, Missouri 64016; telephone: [phone]; facsimile: [phone].

(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) How do I get copies of the documents referenced in this AD? You may obtain copies of the documents referenced in this AD from DG Flugzeugbau, Postbox 41 20, D-76646 Bruchsal, Federal Republic of Germany; telephone: [phone]; facsimile: [phone]. You may examine these documents at FAA, Central Region, Office of the Regional Counsel, 901 Locust, Room 506, Kansas City, Missouri 64106.

Issued in Kansas City, Missouri, on August 3, 2000.

Michael Gallagher,

Manager, Small Airplane Directorate, Aircraft Certification Service.