05-6444. 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 replace the main landing gear front and rear spherical bearings with improved spherical bearings. This proposed AD results from mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Germany. We are issuing this proposed AD to replace front and rear main landing gear bearings that are exposed to high axial loads, which could result in failure of the landing gear bearing. This failure could lead to loss of control on landing.

DATES:

We must receive any comments on this proposed AD by May 3, 2005.

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.
• Government-wide 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: [phone].
• 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.

To get the service information identified in this proposed AD, contact GROB-WERKE, Burkart Grob e.K., Unternehmenbereich Luft-und Raumfahrt, Lettenbachstrasse 9, 86874 Tussenhausen-Mattsies, Germany; telephone: [phone]; facsimile: 011 49 8268 998 200.

To view the comments to this proposed AD, go to http://dms.dot.gov. This is docket number: FAA-2005-20590; Directorate Identifier 2005-CE-13-AD.

FOR FURTHER INFORMATION CONTACT:

Karl Schletzbaum, Aerospace Engineer, ACE-112, Small Airplane Directorate, 901 Locust, Room 301, Kansas City, Missouri 64106; telephone: [phone]; 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-2005-20590; Directorate Identifier 2005-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-2005-20590; Directorate Identifier 2005-CE-13-AD. 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 [phone]) 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-WERKE (GROB) Model G120A airplanes. The LBA reports an incident of a damaged spherical bearing (part number (P/N) S20) installed in the main landing gear on one of the affected airplanes. Evidence showed that the bearing inner ring was shifted against the outer ring. This indicated that the bearing was exposed to high axial loads. Grob has an improved spherical bearing (P/N SSRC 20 C2) that can tolerate higher axial loads.

What is the potential impact if FAA took no action? Main landing gear front and rear bearings exposed to high axial loads could result in failure of the landing gear bearing. This failure could lead to loss of control on landing.

Is there service information that applies to this subject? GROB has issued Service Bulletin No. MSB1121-054, dated November 22, 2004.

What are the provisions of this service information? The service bulletin includes procedures for replacing the front and rear spherical bearings with new improved spherical bearings.

What action did the LBA take? The LBA classified this service bulletin as mandatory and issued German AD Number D-2005-075, dated February 9, 2005, 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 replace front and rear main landing gear bearings exposed to high axial loads, which could result in failure of the landing gear bearing. This failure could lead to loss of control on landing.

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 replacement of the main landing gear front and rear spherical bearings with improved spherical bearings. We have no way of determining the number of airplanes that may need this replacement:

Labor cost	Parts cost	Total cost per airplane	Total cost on U.S. operators
8 work hours × $65 per hour = $65	None. GROB will supply parts free of charge	$520	8 × $520 = $4,160.

Authority for This Rulemaking

What authority does FAA have for issuing this rulemaking action? Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, Section 106 describes the authority of the FAA Administrator. Subtitle VII, Aviation Programs, describes in more detail the scope of the agency's authority.

We are issuing this rulemaking under the authority described in subtitle VII, part A, subpart III, section 44701, “General requirements.” Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this AD.

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 other information as included in the Regulatory Evaluation) 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 “AD Docket FAA-2005-20590; Directorate Identifier 2005-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.

§ 39.13

[Amended]

2. The FAA amends § 39.13 by adding the following new airworthiness directive (AD):

GROB-WERKE: Docket No. FAA-2005-20590; Directorate Identifier 2005-CE-13-AD.

When Is the Last Date I Can Submit Comments on This Proposed AD?

(a) We must receive comments on this proposed airworthiness directive (AD) by May 3, 2005.

What Other ADs Are Affected by This Action?

(b) None.

What Airplanes Are Affected by This AD?

(c) This AD affects Model G120A airplanes, all serial numbers, that are certificated in any category.

What Is the Unsafe Condition Presented in This AD?

(d) This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Germany. The actions specified in this AD are intended to replace front and rear main landing gear bearings that are exposed to high axial loads, which could result in failure of the landing gear bearing. This failure could lead to loss of control on landing.

What Must I Do To Address This Problem?

(e) To address this problem, you must do the following:

Actions	Compliance	Procedures
(1) Replace the main landing gear front and rear spherical bearings (part number (P/N) S20) with improved spherical bearings (P/N SSRC 20 C2)	Within the next 100 hours time-in-service (TIS) after the effective date of this AD, unless already done	Follow GROB Service Bulletin No. MSB1121-054, dated November 22, 2004.
(2) Do not install any main landing front gear and rear spherical bearings (P/N S20)	As of the effective date of this AD	Not applicable.

May I Request an Alternative Method of Compliance?

(f) You may request a different method of compliance or a different compliance time for this AD by following the procedures in 14 CFR 39.19. Unless FAA authorizes otherwise, send your request to your principal inspector. The principal inspector may add comments and will send your request to the Manager, Standards Office, Small Airplane Directorate, FAA. For information on any already approved alternative methods of compliance, contact Karl Schletzbaum, Aerospace Engineer, ACE-112, Small Airplane Directorate, 901 Locust, Room 301, Kansas City, Missouri 64106; telephone: [phone]; facsimile: 816-329-4090.

Is There Other Information That Relates to This Subject?

(g) German AD Number D-2005-075, dated February 9, 2005, also addresses the subject of this AD.

May I Get Copies of the Documents Referenced in This AD?

(h) To get copies of the documents referenced in this AD, contact GROB-WERKE, Burkart Grob e.K., Unternehmenbereich Luft-und Raumfahrt, Lettenbachstrasse 9, 86874 Tussenhausen-Mattsies, Germany; telephone: [phone]; facsimile: 011 49 8268 998 200. To view the AD docket, go to the Docket Management Facility; U.S. Department of Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, Washington, DC, or on the Internet at http://dms.dot.gov. This is docket number. FAA-2005-20590; Directorate Identifier 2005-CE-13-AD.

Issued in Kansas City, Missouri, on March 25, 2005.

Nancy C. Lane,

Acting Manager, Small Airplane Directorate, Aircraft Certification Service.