02-12520. Airworthiness Directives; Glaser-Dirks Flugzeugbau GmbH Models DG-400 and DG-800A 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 all Glaser-Dirks Flugzeugbau GmbH (DG Flugzeugbau) Models DG-400 and DG-800A sailplanes. This proposed AD would require you to inspect the rear plate of the propeller mount for marks and/or cracks and replace if necessary. This proposed AD would also require you to inspect the mounting blocks for cracks and replace if necessary. This proposed AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Germany. The actions specified by this proposed AD are intended to detect and correct cracks in the propeller mount plate and mounting blocks, which could result in reduced structural integrity of the propeller mounting structure. This could lead to a hazardous flight condition or loss of control of the sailplane.

DATES:

The Federal Aviation Administration (FAA) must receive any comments on this proposed rule on or before June 17, 2002.

ADDRESSES:

Submit comments to FAA, Central Region, Office of the Regional Counsel, Attention: Rules Docket No. 2002-CE-12-AD, 901 Locust, Room 506, Kansas City, Missouri 64106. You may view any comments at this location between 8 a.m. and 4 p.m., Monday through Friday, except Federal holidays. You may also send comments electronically to the following address: [e-mail]. Comments sent electronically must contain “Docket No. 2002-CE-12-AD” in the subject line. If you send comments electronically as attached electronic files, the files must be formatted in Microsoft Word 97 for Windows or ASCII text.

You may get service information that applies to this proposed AD from DG Flugzeugbau, Postbox 41 20, D-76625 Bruchsal, Federal Republic of Germany; telephone: ++49 7257-890; facsimile: ++49 7257-8922. You may also view 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 Proposed AD?

The FAA invites comments on this 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 to the address specified under the caption ADDRESSES. We will consider all comments received on or before the closing date. We may amend this proposed rule in light of comments received. Factual information that supports your ideas and suggestions is extremely helpful in evaluating the effectiveness of this proposed AD action and determining whether we need to take additional rulemaking action.

Are There Any Specific Portions of This Proposed AD I Should Pay Attention To?

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

How Can I Be Sure FAA Receives My Comment?

If you want FAA to acknowledge the receipt of your mailed comments, you must include a self-addressed, stamped postcard. On the postcard, write “Comments to Docket No. 2002-CE-12-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 FAA that an unsafe condition may exist on all Model DG-400 and DG-800A sailplanes. The LBA reports that cracks have been found on the rear plate of the propeller mount on one DG-400 sailplane. The cracks were found during regular maintenance. Models DG-400 and DG-800 sailplanes are equipped with the same propeller mount structure.

What Are the Consequences if the Condition Is Not Corrected?

This condition, if left undetected and corrected, could result in reduced structural integrity of the propeller mounting structure. This could lead to a hazardous flight condition or loss of control of the sailplane.

Is There Service Information That Applies to This Subject?

DG Flugzeugbau has issued Technical Note No. 826/42, dated August 30, 2001, which applies to Model DG-400 sailplanes, and Technical Note No. 873/25, dated August 30, 2001, which applies to Model DG-800A sailplanes.

What are the Provisions of This Service Information?

These technical notes include procedures for inspecting the rear plate of the propeller mount for marks and/or cracks and replacing if necessary, and inspecting the mounting blocks for cracks and replacing if necessary.

What Action Did the LBA take?

The LBA classified these technical notes as mandatory and issued German AD 2001-346, dated December 13, 2001, and German AD 2001-340, dated December 13, 2001, in order 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.

Pursuant to 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 This 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 Models DG-400 and DG-800A sailplanes of the same type design that are on the U.S. registry;

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

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

What Would This Proposed AD Require?

This proposed AD would require you to incorporate the actions in the previously-referenced service bulletin.

Cost Impact

How many sailplanes would this proposed AD impact?

We estimate that this proposed AD affects 43 sailplanes in the U.S. registry.

What would be the cost impact of this proposed AD on owners/operators of the affected sailplanes?

We estimate the following costs to accomplish the proposed inspection:

Labor cost	Parts cost	Total cost per sailplane	Total cost on U.S. operators
1 workhour × $60 per hour = $60	No parts required for the inspection	$60	43 × $60 = $2,580

We estimate the following costs to accomplish any necessary replacements that would be required based on the results of the proposed inspection. We have no way of determining the number of sailplanes that may need such replacement:

Labor cost	Parts cost	Total cost per sailplane
2 workhours × $60 per hour = $120	$400	$120 + $400 = $520

Compliance Time of This Proposed AD

What Would Be the Compliance Time of This Proposed AD?

The compliance time of the proposed inspection is “within the next 25 hours time-in-service (TIS) or 3 calendar months after the effective date of this AD, whichever occurs first.”

Why Is the Compliance Time of This Proposed AD Presented in Both Hours TIS and Calendar Time?

The unsafe condition on these sailplanes is not a result of the number of times the sailplane is operated. Sailplane operation varies among operators. For example, one operator may operate the sailplane 50 hours TIS in 3 months while it may take another operator 12 months or more to accumulate 50 hours TIS. For this reason, the FAA has determined that the compliance time of this proposed AD should be specified in both hours time-in-service (TIS) and calendar time in order to ensure this condition is not allowed to go uncorrected over time.

Regulatory Impact

Would This Proposed AD Impact Various Entities?

The regulations proposed herein 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 promulgated, 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.

§ 39.13

[Amended]

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

Glaser-Dirks Flugzeugbau GMBH: Docket No. 2002-CE-12-AD

(a) What sailplanes are affected by this AD? This AD affects Models DG-400 and DG-800A sailplanes, all serial numbers, that are certificated in any category.

(b) Who must comply with this AD? Anyone who wishes to operate any of the sailplanes identified in paragraph (a) of this AD must comply with this AD.

(c) What problem does this AD address? The actions specified by this AD are intended to detect and correct cracks in the propeller mount plate, which could result in reduced structural integrity of the propeller mounting structure This could lead to a hazardous flight condition or loss of control of the sailplane.

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

Actions	Compliance	Procedures
(1) Accomplish the following inspections: (i) Inspect the rear plate of the propeller mount for cracks and any marks made by the mounting bolt washer; and (ii) Inspect the mounting blocks for the rear plate of the propeller mount for cracks.	Inspect within the next 25 hours time-in-service (TIS) or 3 calendar months after the effective date of this AD, whichever occurs first.	In accordance with DG Flugzeugbau Technical Note No. 826/42, dated August 30, 2001, or DG Flugzeugbau Technical Note No. 873/25, dated August 30, 2001, as applicable maintenance manual.
(2) Accomplish the following if cracks and/or marks are found during the inspections required in paragraph (d)(1) of this AD: (i) If a mark made by the mounting bolt washer is found and the mark is 0.1 mm deep or less and no cracks are found on the rear plate of the propeller mount, polish out the mark using standard maintenance practices; (ii) If a mark made by the moutning bolt washer is found and the mark is more than 0.1 mm deep and/or cracks are found on the rear plate of the propeller mount, replace the rear plate with a new one. Use new bolts and washers as required by paragraph (d)(3) of this AD; and (iii) If cracks are found on the mounting block(s) of the rear plate of the propeller mount, replace the mounting block(s) with a new one. Use new bolts and washers as required by paragraph (d)(3) of this AD.	Prior to further flight after the inspections required in paragraph (d)(1) of this AD.	In accordance with DG Flugzeugbau Technical Note No. 826/42, dated August 30, 2001, or DG Flugzeugbau Technical Note No. 873/25, dated August 30, 2001, as applicable, and the applicable maintenance manual.
(3) Reinstall the rear plate of the propeller mount to the mounting blocks using new bolts, M10×25 DIN912-8.8zn with the aluminum washer S48 (or FAA-approved equivalent parts)	Prior to further flight after the inspections required in paragraph (d)(1) of this AD and/or after the replacements required in paragraph (d)(2) of this AD.	In accordance with DG Flugzeugbau Technical Note No. 826/42, dated August 30, 2001, or DG Flugzeugbau Technical Note No. 873/25, dated August 30, 2001, as applicable, and the applicable maintenance manual.
(4) Do not install any rear propeller mount plate mounting bolts that are not bolts M10×25 DIN912-8.8zn with the aluminum washer S48 (or FAA-approved equivalent parts)	As of the effective date of this AD.	Not applicable.

(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 Standards Office 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 Standards Office Manager.

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 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 get copies of the documents referenced in this AD from DG Flugzeugbau, Postbox 41 20, D-76625 Bruchsal, Federal Republic of Germany. You may view these documents at FAA, Central Region, Office of the Regional Counsel, 901 Locust, Room 506, Kansas City, Missouri 64106.

Note 2:

The subject of this AD is addressed in German AD 2001-346, dated December 13, 2001, and German AD 2001-340, dated December 13, 2001.

Issued in Kansas City, Missouri, on May 10, 2002.

Michael Gallagher,

Manager, Small Airplane Directorate, Aircraft Certification Service.