Airworthiness Directives; DG Flugzeugbau GmbH Model DG-500MB 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 GmbH (DG Flugzeugbau) Model DG-500MB sailplanes equipped with a SOLO 2625 02 engine.

The proposed AD would require you to remove the engine from the propeller mount; install additional access holes in the propeller mount; install the modified engine to the propeller mount; do a ground test run; and replace the digital engine indicator circuit breaker with a new circuit breaker. 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 by the proposed AD are intended to correct propeller drive belt tension that could cause damage to the engine crankshaft and to replace an inadequate circuit breaker. This could lead to engine failure and loss of sailplane control.

DATES:

The Federal Aviation Administration (FAA) must receive any comments on this proposed rule by February 1, 2001.

ADDRESSES:

Send three copies of your comments to FAA, Central Region, Office of the Regional Counsel, Attention: Rules Docket No. 99-CE-89-AD, 901 Locust, Room 506, Kansas City, Missouri 64106. Comments may be inspected at this location between 8 a.m. and 4 p.m., Monday through Friday, except holidays.

You may get service information that applies to the proposed AD from DG Flugzeugbau GmbH, Postbox 41 20, D-76646 Bruchsal, Federal Republic of Germany; telephone: +49 7257-890; facsimile: +49 7257-8922. You may also read 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 64106; telephone: (816) 329-4144; facsimile: (816) 329-4090.

SUPPLEMENTARY INFORMATION:

Comments Invited

How do I comment on the proposed AD? We invite your comments on the proposed rule. You may send whatever written data, views, or arguments you choose. You need to include the rule's docket number and send your comments in triplicate to the address specified under the caption ADDRESSES. We will consider all comments received by 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 proposed 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 require a change to the proposed rule. You may look at 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.

We are re-examining 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-89-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, notified FAA that an unsafe condition may exist on all DG Flugzeugbau Model DG-500MB sailplanes equipped with a SOLO 2625 02 engine. The LBA reports that the service history for the SOLO 2625 02 engine shows a need to modify the front crank shaft bearing. Additionally, the digital engine indicator circuit breaker amperage is too low for use and needs replacement.

What are the consequences if the condition is not corrected? The actions specified by the proposed AD are intended to correct propeller drive belt tension that could cause damage to the engine crankshaft, and to replace an inadequate circuit breaker. Such failure could result in loss of power and consequently the loss of sailplane control.

Is there service information that applies to this subject? DG Flugzeugbau has issued: Technical Note No. 843/13, dated November 3, 1999. SOLO, the engine manufacturer, has issued Technical Note 4600-1.

What are the provisions of these technical notes? These technical notes includes procedures for:

—Removing the engine from the propeller mount;

—Modifying the engine;

—Installing additional access holes in the propeller mount;

—Installing the modified engine to the propeller mount;

—Doing a ground test run; and

—Replacing the digital engine indicator circuit breaker with a new circuit breaker.

What action did LBA take? The LBA classified this DG Flugzeugbau technical note as mandatory and issued German AD Number 1999-383, dated December 1, 1999, to ensure the continued airworthiness of these sailplanes in Germany.

Was this in accordance with the bilateral airworthiness agreement? These sailplane models are manufactured in Germany and are type certificated 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 has kept FAA informed 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 technical note referenced above; and determined that:

—The unsafe condition referenced in this document exists or could develop on other DG Flugzeugbau Model DG-500MB sailplanes of the same type design that are equipped with a SOLO 2625 02 engine;

—The actions specified in the previously-referenced technical note should be accomplished on the affected sailplanes; and

—AD action should be taken in order to correct this unsafe condition.

What would the proposed AD require? This proposed AD would require you to incorporate the actions in the previously referenced technical notes.

Cost Impact

How many sailplanes would the proposed AD impact? We estimate that the proposed AD affects 1 sailplane in the U.S. registry.

What would be the cost impact of the proposed AD on owners/operators of the affected sailplanes? We estimate the following costs to do the proposed modification:

Regulatory Impact

Would this proposed AD impact various entities? The regulations proposed here would 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 proposed rule would not have federalism implications under Executive Order 13132.

Would this proposed AD involve a significant rule or regulatory action? For the reasons discussed above, I certify that this proposed 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) if issued, 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 draft regulatory evaluation prepared for this action has been placed 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
• 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.