Airworthiness Directives; GROB-WERKE Model G120A Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to adopt a new airworthiness directive (AD) for all GROB-WERKE (GROB) Model G120A airplanes. This proposed AD would require you to repetitively inspect visually the area between the vertical stabilizer main spar and the nearby vertical stabilizer skin for any disbonding/crack; repair any disbonding/crack found; and calculate weight and balance after any repair. This proposed AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Germany. We are issuing this proposed AD to detect and correct any disbonding/crack in the area between the vertical stabilizer main spar and nearby stabilizer skin, which could result in possible structural failure. This failure could lead to difficulty in airplane flight control.

DATES:

We must receive any comments on this proposed AD by August 16, 2004.

ADDRESSES:

Use one of the following to submit comments on this proposed AD:

• DOT Docket Web site: Go to http://dms.dot.gov and follow the instructions for sending your comments electronically.
• Governmentwide rulemaking Web site: Go to http://www.regulations.gov and follow the instructions for sending your comments electronically.
• Mail: Docket Management Facility; U.S. Department of Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, Washington, DC 20590-001.
• Fax: 1-202-493-2251.
• Hand Delivery: Room PL-401 on the plaza level of the Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

You may get the service information identified in this proposed AD from GROB Luft-und Raumfahrt, Lettenbachstrasse 9, D-86874 Tussenhausen-Mattsies, Federal Republic of Germany; telephone: 49 8268 998139; facsimile: 49 8268 998200.

You may view the comments to this proposed AD in the AD docket on the Internet at http://dms.dot.gov.

FOR FURTHER INFORMATION CONTACT:

Karl Schletzbaum, Aerospace Engineer, FAA, Small Airplane Directorate, 901 Locust, Room 301, Kansas City, Missouri 64106; telephone: (816) 329-4146; facsimile: (816) 329-4090.

SUPPLEMENTARY INFORMATION:

Comments Invited

How do I comment on this proposed AD? We invite you to submit any written relevant data, views, or arguments regarding this proposal. Send your comments to an address listed under ADDRESSES. Include the docket number, “FAA-2004-18030; Directorate Identifier 2004-CE-13-AD” at the beginning of your comments. We will post all comments we receive, without change, to http://dms.dot.gov,, including any personal information you provide. We will also post a report summarizing each substantive verbal contact with FAA personnel concerning this proposed rulemaking. Using the search function of our docket web site, anyone can find and read the comments received into any of our dockets, including the name of the individual who sent the comment (or signed the comment on behalf of an association, business, labor union, etc.). This is docket number FAA-2004-18030. You may review the DOT's complete Privacy Act Statement in the Federal Register published on April 11, 2000 (65 FR 19477-78) or you may visit http://dms.dot.gov.

Are there any specific portions of this proposed AD I should pay attention to? We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this proposed AD. If you contact us through a nonwritten communication and that contact relates to a substantive part of this proposed AD, we will summarize the contact and place the summary in the docket. We will consider all comments received by the closing date and may amend this proposed AD in light of those comments and contacts.

Docket Information

Where can I go to view the docket information? You may view the AD docket that contains the proposal, any comments received, and any final disposition in person at the DMS Docket Offices between 9 a.m. and 5 p.m. (eastern standard time), Monday through Friday, except Federal holidays. The Docket Office (telephone 1-800-647-5227) is located on the plaza level of the Department of Transportation NASSIF Building at the street address stated in ADDRESSES. You may also view the AD docket on the Internet at http://dms.dot.gov. The comments will be available in the AD docket shortly after the DMS receives them.

Discussion

What events have caused this proposed AD? The Luftfahrt-Bundesamt (LBA), which is the airworthiness authority for Germany, recently notified FAA that an unsafe condition may exist on all GROB Model G120A airplanes. The LBA reports that a routine inspection of a Model G120A-I airplane found disbonding/cracking in the area between the vertical stabilizer main spar and nearby vertical stabilizer skin near the VOR (very high frequency omnidirectional range) antenna. A fleet-wide inspection of the Model G120A-I airplane fleet found one other Model G120A-I airplane with disbonding/cracking in the same area. The most likely reason for the disbonding/cracking was an incorrectly installed antenna support bracket, which caused permanent tension on the bonding seam. This resulted in disbonding/cracking in the area near the VOR antenna.

What is the potential impact if FAA took no action? Any disbonding/crack in the area between the vertical stabilizer main spar and nearby stabilizer skin could result in possible structural failure. This failure could lead to difficulty in airplane flight control.

Is there service information that applies to this subject? GROB has issued Service Bulletin No. MSB1121-049, dated April 20, 2004.

What are the provisions of this service information? The service information includes procedures for:

—Inspecting visually the area between the vertical stabilizer main spar and the nearby vertical stabilizer skin for any disbonding/cracking); and

—Contacting the manufacturer for a repair instruction if any disbonding/crack is found.

What action did the LBA take? The LBA classified this service bulletin as mandatory and issued German AD Number D-2004-204, dated April 23, 2004, to ensure the continued airworthiness of these airplanes in Germany.

Did the LBA inform the United States under the bilateral airworthiness agreement? These GROB Model G120A airplanes 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.

Under this bilateral airworthiness agreement, the LBA has kept us informed of the situation described above.

FAA's Determination and Requirements of This Proposed AD

What has FAA decided? We have examined the LBA's findings, reviewed all available information, and determined that AD action is necessary for products of this type design that are certificated for operation in the United States.

Since the unsafe condition described previously is likely to exist or develop on other GROB Model G120A airplanes of the same type design that are registered in the United States, we are proposing AD action to detect and correct any disbonding/crack in the area between the vertical stabilizer main spar and nearby stabilizer skin, which could result in possible structural failure. This failure could lead to difficulty in airplane flight control.

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

How does the revision to 14 CFR part 39 affect this proposed AD? On July 10, 2002, we published a new version of 14 CFR part 39 (67 FR 47997, July 22, 2002), which governs 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 airplanes would this proposed AD impact? We estimate that this proposed AD affects 6 airplanes in the U.S. registry.

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

We estimate the following costs to do any necessary repairs that would be required based on the results of this proposed inspection. We have no way of determining the number of airplanes that may need this repair:

Regulatory Findings

Would this proposed AD impact various entities? We have determined that this proposed AD would not have federalism implications under Executive Order 13132. This proposed AD 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.

Would this proposed AD involve a significant rule or regulatory action? For the reasons discussed above, I certify that this proposed 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 proposed 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 the docket number, “FAA-2004-18030; Directorate Identifier 2004-CE-13-AD” in your request.

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 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.