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Proposed Rule

Airworthiness Directives; Burkhart GROB Luft-UND Raumfahrt GmbH & CO KG Models G103 TWIN ASTIR, G103A TWIN II ACRO, and G103C TWIN III ACRO Sailplanes

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AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to revise 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 restriction placards (as applicable), and revise the flight and maintenance manual. This proposed AD would retain all the actions in AD 2003-19-14 for all Model G103 TWIN ASTIR sailplanes, would remove Model G103 TWIN II from the applicability, and would retain the aerobatic maneuver restriction for Model G103C TWIN III ACRO sailplanes. This proposed AD would also 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 would also 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 is also included in this proposed AD.

DATES:

We must receive any comments on this proposed AD by May 21, 2004.

ADDRESSES:

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

  • By mail: FAA, Central Region, Office of the Regional Counsel, Attention: Rules Docket No. 2003-CE-35-AD, 901 Locust, Room 506, Kansas City, Missouri 64106.
  • By fax: (816) 329-3771.
  • By e-mail: 9-ACE-7-Docket@faa.gov. Comments sent electronically must contain “Docket No. 2003-CE-35-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.

You may get the service information identified in this proposed AD from GROB Luft-und Raumfahrt, Lettenbachstrasse 9, D-86874 Tussenhausen-Mattsies, Germany; telephone: 011 49 8268 998139; facsimile: 011 49 8268 998200; email: productsupport@grob-aerospace.de.

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.

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FOR FURTHER INFORMATION CONTACT:

Gregory A. Davison, Aerospace Engineer, FAA, Small Airplane Directorate, 901 Locust, Room 301, Kansas City, Missouri 64106; telephone: (816) 329-4130; facsimile: (816) 329-4090.

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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 “AD Docket No. 2003-CE-35-AD” in the subject line of your comments. If you want us to acknowledge receipt of your mailed comments, send us a self-addressed, stamped postcard with the docket number written on it. We will date-stamp your postcard and mail it back to you.

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.

Discussion

Has FAA taken any action to this point? 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 proposed 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). Start Printed Page 25038

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

—reinstate the original flight speed limitations except for rough air (VB) and maneuvering speeds (VA); 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 are the consequences if the condition is not corrected? 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.

Is there service information that applies to this subject? Grob has issued Mandatory Service Bulletin No. MSB315-65, dated September 15, 2003; Optional Service Bulletin OSB 315-66, dated October 16, 2003, and Work Instruction for Optional Service Bulletin OSB-315-66, dated October 16, 2003.

What are the provisions of this service information? Mandatory Service Bulletin No. MSB315-65, dated September 15, 2003, includes procedures for:

—modifying the airspeed indicators;

—installing a revised flight speed reduction placard; and

—revising the flight and maintenance manual (as applicable).

Optional Service Bulletin OSB 315-66, dated October 16, 2003, and Work Instruction for Optional Service Bulletin OSB-315-66, dated October 16, 2003, include procedures for installing stringers in the rear fuselage for Models G103A TWIN II ACRO (aerobatic category) and G103C TWIN III ACRO (aerobatic category) sailplanes to terminate the flight limitation restrictions for aerobatic maneuvers.

What action did the LBA take? The LBA classified Service Bulletin No. MSB315-65, dated September 15, 2003, as mandatory and issued German AD Number D-2004-002, dated January 23, 2004, to ensure the continued airworthiness of these sailplanes in Germany.

Did the LBA inform the United States under the bilateral airworthiness agreement? These GROB Models G103 TWIN ASTIR, G103A TWIN II ACRO, and G103C TWIN III ACRO sailplanes 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 Models G103 TWIN ASTIR, G103A TWIN II ACRO, and G103C TWIN III ACRO sailplanes of the same type design that are registered in the United States, we are proposing AD action to prevent the possibility of damage to the fuselage during limit load flight due to inadequate safety margins designed into the fuselage. Such a condition could result in reduced structural integrity of the fuselage and lead to loss of control of the sailplane.

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

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 sailplanes would this proposed AD impact? We estimate that this proposed AD affects 94 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 modifications to the airspeed indicators, flight limitations placards, and revising the flight and maintenance manual:

Labor costParts costTotal cost per sailplaneTotal cost on U.S. operators
1 workhour × $65 = $65Not applicable$65$65 × 94 = $6,110.

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

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

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: Start Printed Page 25039

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 “AD Docket No. 2003-CE-35-AD” in your request.

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List of Subjects in 14 CFR Part 39

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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:

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PART 39—AIRWORTHINESS DIRECTIVES

1. The authority citation for part 39 continues to read as follows:

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Authority: 49 U.S.C. 106(g), 40113, 44701.

End Authority
[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):

Burkhart Grob Luft—UND Raumfahrt GmbH & Co KG: Docket No. 2003-CE-35-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 21, 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:

ModelSerial Nos.
G103 TWIN ASTIRAll 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 proposed 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:

ActionsComplianceProcedures
(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, dated June 30, 2003.
(2) For G103A TWIN II ACRO (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 placards on Model G103A TWIN II ACRO (aerobatic category) sailplanes:Within the next 25 hours time-in-service (TIS) after the effective date of this AD.Follow Grob Service Bulletin No. MSB315-65, dated September 15, 2003.

(iii) Install the following placards on Model G103C TWIN III ACRO (aerobatic category) sailplanes:
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  RUL='s'>
(3) For G103A TWIN II ACRO (acrobatic category) and G103C TWIN III ACRO (acrobatic 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 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: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.

(iii) Install the following flight limitation placard on Model G103C TWIN III ACRO (aerobatic category) sailplanes:

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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: (816) 329-4130; facsimile: (816) 329-4090.

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

(g) You may get copies of the documents referenced in this AD from GROB Luftund Raumfahrt, Lettenbachstrasse 9, D-86874 Tussenhausen-Mattsies, Germany; telephone: 011 49 8268 998139; facsimile: 011 49 8268 998200; email: productsupport@grob-aerospace.de. You may view these documents at FAA, Central Region, Office of the Regional Counsel, 901 Locust, Room 506, Kansas City, Missouri 64106.

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.

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Issued in Kansas City, Missouri, on April 26, 2004.

Dorenda D. Baker,

Manager, Small Airplane Directorate, Aircraft Certification Service.

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[FR Doc. 04-10145 Filed 5-4-04; 8:45 am]

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