05-11042. Airworthiness Directives; GROB-WERKE Model G120A Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Final rule.

SUMMARY:

The FAA adopts a new airworthiness directive (AD) for all GROB-WERKE (GROB) Model G120A airplanes. This AD requires you to replace the main landing gear front and rear spherical bearings with improved spherical bearings. This AD results from mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Germany. We are issuing this AD to replace front and rear main landing gear bearings that are susceptible to damage when 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:

This AD becomes effective on July 18, 2005.

As of July 18, 2005, the Director of the Federal Register approved the incorporation by reference of certain publications listed in the regulation.

ADDRESSES:

To get the service information identified 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 20590-001 or on the Internet at http://dms.dot.gov. The docket number is 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:

Discussion

What events have caused this 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 that are susceptible to damage when exposed to high axial loads could result in failure of the landing gear bearing. This failure could lead to loss of control on landing.

Has FAA taken any action to this point? We issued a proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an AD that would apply to all GROB-WERKE (GROB) Model G120A airplanes. This proposal was published in the Federal Register as a notice of proposed rulemaking (NPRM) on April 1, 2005 (70 FR 16769). The NPRM proposed to require you to replace the main landing gear front and rear spherical bearings with improved spherical bearings.

Comments

Was the public invited to comment? We provided the public the opportunity to participate in developing this AD. We received no comments on the proposal or on the determination of the cost to the public.

Conclusion

What is FAA's final determination on this issue? We have carefully reviewed the available data and determined that air safety and the public interest require adopting the AD as proposed except for minor editorial corrections. We have determined that these minor corrections:

—Are consistent with the intent that was proposed in the NPRM for correcting the unsafe condition; and

—Do not add any additional burden upon the public than was already proposed in the NPRM.

Changes to 14 CFR Part 39—Effect on the AD

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

What is the cost impact of this AD on owners/operators of the affected airplanes? We estimate the following costs to do the 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	6 × $520 = $3,120

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

Will this AD impact various entities? We have determined that this AD will not have federalism implications under Executive Order 13132. This AD will 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.

Will this AD involve a significant rule or regulatory action? For the reasons discussed above, I certify that this 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 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 “Docket No. 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
• Incorporation by reference
• Safety

Adoption of the Amendment

Accordingly, under the authority delegated to me by the Administrator, the Federal Aviation Administration amends 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 AD to read as follows:

2005-11-08 GROB-WERKE: Amendment 39-14110; Docket No. FAA-2005-20590; Directorate Identifier 2005-CE-13-AD.

When Does This AD Become Effective?

(a) This AD becomes effective on July 18, 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 susceptible to damage when 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 any part number (P/N) S20 main landing gear front and rear spherical bearings with improved spherical bearings (P/N SSRC 20 C2)	Within the next 100 hours time-in-service (TIS) after July 18, 2005 (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 P/N S20 main landing gear front and rear spherical bearings	As of July 18, 2005 (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, 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.

Does This AD Incorporate Any Material by Reference?

(h) You must do the actions required by this AD following the instructions in GROB Service Bulletin No. MSB1121-054, dated November 22, 2004. The Director of the Federal Register approved the incorporation by reference of this service bulletin in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. To get a copy of this service information, 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 review copies of this service information, go to the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, go to: http://www.archives.gov/​federal_​register/​code_​of_​federal_​regulations/​ibr_​locations.html or call [phone]. 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 20590-001 or on the Internet at http://dms.dot.gov. The docket number is FAA-2005-20590; Directorate Identifier 2005-CE-13-AD.

Issued in Kansas City, Missouri, on May 26, 2005.

Kim Smith,

Acting Manager, Small Airplane Directorate, Aircraft Certification Service.