04-13566. Airworthiness Directives; BURKHART GROB LUFT-UND RAUMFAHRT GmbH & CO KG Models G103 TWIN ASTIR, G103A TWIN II ACRO, and G103C TWIN III ACRO Sailplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Final rule.

SUMMARY:

The FAA revises Airworthiness Directive (AD) 2003-19-14 which applies to all BURKHART GROB LUFT—UND RAUMFAHRT GmbH & CO KG (GROB) Models G103 TWIN ASTIR, G103 TWIN II, G103A TWIN II ACRO, and G103C TWIN III ACRO sailplanes. AD 2003-19-14 currently requires you to modify the airspeed indicators, install flight speed reduction and aerobatic maneuver restrictions placards (as applicable), and revise the flight and maintenance manual. This AD retains all the actions in AD 2003-19-14 for all Model G103 TWIN ASTIR sailplanes, removes Model G103 TWIN II from the applicability, and retains the aerobatic maneuver restriction for Model G103C TWIN III ACRO sailplanes. This AD also requires you to revise the modification to airspeed indicators, install a revised flight speed reduction placard, and revise the flight and maintenance manual for certain Models G103A TWIN II ACRO, and G103C TWIN III ACRO sailplanes. Simple Aerobatic maneuvers are also re-approved for Model G103A TWIN II ACRO sailplanes. An option for modifying the rear fuselage for Models G103A TWIN II ACRO and G103C TWIN III ACRO sailplanes that terminates the flight limitation restrictions for aerobatic maneuvers is also included in this AD.

DATES:

This AD becomes effective on August 12, 2004.

As of August 12, 2004, the Director of the Federal Register approved the incorporation by reference of certain publications listed in the regulation.

ADDRESSES:

You may get the service information identified in this AD from GROB Luft-und Raumfahrt, Lettenbachstrasse 9, D-86874 Tussenhausen-Mattsies, Germany; telephone: [phone]; facsimile: 011 49 8268 998200; e-mail: [e-mail].

You may view the AD docket at FAA, Central Region, Office of the Regional Counsel, Attention: Rules Docket No. 2003-CE-35-AD, 901 Locust, Room 506, Kansas City, Missouri 64106. Office hours are 8 a.m. to 4 p.m., Monday through Friday, except Federal holidays.

FOR FURTHER INFORMATION CONTACT:

Gregory A. Davison, Aerospace Engineer, FAA, Small Airplane Directorate, 901 Locust, Room 301, Kansas City, Missouri 64106; telephone: [phone]; facsimile: [phone].

SUPPLEMENTARY INFORMATION:

Discussion

What events have caused this AD? Reports from the Luftfahrt-Bundesamt (LBA), which is the airworthiness authority for Germany, that the safety margins established into the design of the fuselage may not have been sufficient to sustain limit loads during certain maneuvers and during flight at certain speeds caused us to issue AD 2003-19-14, Amendment 39-13317 (68 FR 56152, September 30, 2003). AD 2003-19-14 requires the following:

—Modifying the airspeed indicators;

—Installing placards restricting flight speeds, prohibiting aerobatic maneuvers, and restricting load limits; and

—Incorporating revisions to the flight and maintenance manuals.

AD 2003-19-14 was issued as an interim action until the manufacturer completed further investigations into the effects of certain flight conditions on the fuselage structure and the development of corrective procedures.

What has happened since AD 2003-19-14 to initiate this AD action? The manufacturer conducted further static strength tests to verify the safety margin of the fuselage on the affected sailplanes. The results of these tests verified the following:

For Model G103 TWIN ASTIR sailplanes:

—Retain all flight limitation restrictions in AD 2003-19-14.

For Model G103 TWIN II sailplanes:

—Reinstate the original flight speed limitations and maneuver operations. For Model G103A TWIN II ACRO (utility category) sailplanes:

—Reinstate the original flight speed limitations and maneuver operations; and

—Allow only basic aerobatic maneuvers (spins, lazy eights, chandelles, stall turns, steep turns, and positive loops).

For Model G103A TWIN II ACRO (aerobatic category) sailplanes:

—Reinstate the original flight speed limitations except for rough air (V_B) and maneuvering speeds (V_A); and

—Allow only basic aerobatic maneuvers (spins, lazy eights, chandelles, stall turns, steep turns, and positive loops).

For Model G103C TWIN III ACRO sailplanes:

—Increase airspeed limits specified in AD 2003-19-14 but maintain a reduction from the original limitations; and

—Retain restrictions in AD 2003-19-14 on all aerobatic flights, including simple maneuvers, and cloud flying.

The manufacturer has also developed a modification for Models G103A TWIN II ACRO (aerobatic category) and G103C TWIN III ACRO sailplanes (aerobatic category). When this modification is incorporated, full acrobatic status is restored to these sailplanes.

What is the potential impact if FAA took no action? If not prevented, damage to the fuselage during limit load flight could result in reduced structural integrity. This condition could lead to loss of control of the sailplane.

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 certain GROB Models G103 TWIN ASTIR, G103A TWIN II ACRO, and G103C TWIN III ACRO sailplanes. This proposal was published in the Federal Register as a notice of proposed rulemaking (NPRM) on May 5, 2004 (69 FR 11111). The NPRM proposed to retain all the actions in AD 2003-19-14 for all Model G103 TWIN ASTIR sailplanes, remove Model G103 TWIN II from the applicability, and retain the aerobatic maneuver restriction for Model G103C TWIN III ACRO sailplanes. The NPRM also proposed to require you to revise the modification to airspeed indicators, install a revised flight speed reduction placard, and revise the flight and maintenance manual for certain Models G103A TWIN II ACRO, and G103C TWIN III ACRO sailplanes. Simple Aerobatic maneuvers were also proposed to be re-approved for Model G103A TWIN II ACRO sailplanes. An option for modifying the rear fuselage for Models G103A TWIN II ACRO and G103C TWIN III ACRO sailplanes that terminates the flight limitation restrictions for aerobatic maneuvers was also included in the NPRM.

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 sailplanes does this AD impact? We estimate that this AD affects 94 sailplanes in the U.S. registry.

What is the cost impact of this AD on owners/operators of the affected sailplanes? We estimate the following costs to accomplish the modifications to the airspeed indicators, flight limitations placards, and revising the flight and maintenance manual:

Labor cost	Parts cost	Total cost per Sailplane	Total Cost on U.S. operators
1 workhour × $65 = $65	Not applicable.	$65	$65 × 94 =$6,110

We estimate the following costs to accomplish the fuselage modification on 35 of the affected sailplanes in the aerobatic category:

Labor cost	Parts cost	Total cost per sailplane
30 workhours × $65 = $1,950	$5,307	$7,257

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 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 No. 2003-CE-35-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. The FAA amends § 39.13 by removing Airworthiness Directive (AD) 2003-19-14, Amendment 39-13317 ( 68 FR 56152, September 30, 2003), and by adding the following new airworthiness directive (AD):

2003-19-14 R1 BURKHART GROB LUFT-UND RAUMFAHRT GmbH & CO KG: Amendment 39-13676; Docket No. 2003-CE-35-AD.

When Does This AD Become Effective?

(a) This AD becomes effective on August 12, 2004.

What Other ADs Are Affected by This Action?

(b) This AD revises AD 2003-19-14.

What Sailplanes Are Affected by This AD?

(c) This AD affects the following sailplane models and serial numbers that are certificated in any category:

Model	Serial numbers
G103 TWIN ASTIR	All serial numbers.
G103A TWIN II ACRO (aerobatic category)	3544 through 34078 with suffix “K”.
G103C TWIN III ACRO (aerobatic category)	34101 through 34203.

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 prevent the possibility of damage to the fuselage during limit load flight. Such a condition could result in reduced structural integrity of the fuselage and lead to loss of control of the sailplane.

What Must I Do To Address This Problem?

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

Actions	Compliance	Procedures
(1) For G103 TWIN ASTIR sailplanes:  (i) modify the airspeed indicators;  (ii) install flight speed, aerobatic maneuver, and load limit restriction placards; and  (iii) revise the flight and maintenance manual	Within the next 10 hours time-in-service (TIS) after October 20, 2003 (the effective date of AD 2003-19-14)	Following GROB Alert Service Bulletin No. ASB315-64/2, dated August 13, 2003.
(2) For G103A TWIN II ACRO (utility and acrobatic category) and G103C TWIN III ACRO (acrobatic category) sailplanes:  (i) re-set the airspeed indicator to the new placard limitations; and  (ii) install the following 2 placards on Model G103A TWIN II ACRO (aerobatic category) sailplanes:

(iii) install the following 2 placards on Model G103C TWIN III ACRO (aerobatic category) sailplanes:	Within the next 25 hours time-in-service (TIS) after August 12, 2004 (the effective date of this AD)	Follow GROB Service Bulletin No. MSB315-65, dated September 15, 2003.

(3) For G103A TWIN II ACRO (acrobatic category) and G103 TWIN III ACRO (ascrobatic Category) sailplanes: as an alternative to the flight restrictions in paragraph (e)(2) of this AD, you may install additional stringers in the rear fuselage section. Installing additional stringers terminates the flight restrictions in paragraph (e)(2) of this AD.	At any time after August 12, 2004 (the effective date of this AD)	Follow GROB Service Bulletin No. OSB 315-66, dated October 16, 2003, and Work Instruction for OSB 315-66, dated October 16, 2003.
(4) For G103A TWIN II ACRO (acrobatic category) and G103C TWIN III ACRO (acrobatic category) sailplanes: only if you installed the additional stringers specified in paragraph (e)(3) of this AD, do the following:  (i) remove the placard prohibiting all aerobatic maneuvers;  (ii) install the following flight limitation placard on Model G103A TWIN II ACRO (aerobatic category) sailplanes:

(iii) install the following flight limitation placard on Model G103C TWIN II ACRO (aerobatic category) sailplanes:	Prior to further flight after doing the actions in paragraph (e)(3) of this AD	Follow GROB Service Bulletin No. OSB 315-66, dated October 16, 2003.

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 Gregory A. Davison, Aerospace Engineer, FAA, Small Airplane Directorate, 901 Locust, Room 301, Kansas City, Missouri 64106; telephone: [phone]; facsimile: [phone].

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

(g) You must do the actions required by this AD following the instructions in GROB Alert Service Bulletin No. ASB315-64/2, dated August 13, 2003; GROB Service Bulletin No. MSB315-65, dated September 15, 2003; GROB Service Bulletin No. OSB 315-66, dated October 16, 2003; and GROB Work Instruction for OSB 315-66, dated October 16, 2003. 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. You may get a copy from GROB Luft- und Raumfahrt, Lettenbachstrasse 9, D-86874 Tussenhausen-Mattsies, Germany; telephone: [phone]; facsimile: 011 49 8268 998200; e-mail: [e-mail]. You may review copies at FAA, Central Region, Office of the Regional Counsel, 901 Locust, Room 506, Kansas City, Missouri 64106; or at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call [phone], or go to: http://www.archives.gov/​federal_​register/​code_​of_​federal_​regulations/​ibr_​locations.html.

Is There Other Information That Relates to This Subject?

(h) German AD Number D-2004-002, dated January 23, 2004, also addresses the subject of this AD.

Issued in Kansas City, Missouri, on June 9, 2004.

David R. Showers,

Acting Manager, Small Airplane Directorate, Aircraft Certification Service.