E8-5147. Airworthiness Directives; Gulfstream Aerospace LP Model Astra SPX and 1125 Westwind Astra Airplanes and Gulfstream 100 Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

We propose to adopt a new airworthiness directive (AD) for the products listed above. This proposed AD results from mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as:

Two of the fasteners used to attach the “scissors” to the horizontal and the vertical stabilizers were found broken during routine maintenance. The highest loads on the “scissors” occur when using high reverse thrust. Therefore, the reverse thrust must be limited to idle in order to keep the loads at a sufficiently low level to preclude any structural problem. * * *

Failure of the attachment fasteners could result in possible in-flight loss of a horizontal or vertical stabilizer and consequent loss of control of the airplane. The proposed AD would require actions that are intended to address the unsafe condition described in the MCAI.

DATES:

We must receive comments on this proposed AD by April 14, 2008.

ADDRESSES:

You may send comments by any of the following methods:

• Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
• Fax: [phone].
• Mail: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590.
• Hand Delivery: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-40, 1200 New Jersey Avenue, SE., Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

Examining the AD Docket

You may examine the AD docket on the Internet at http://www.regulations.gov; or in person at the Docket Operations office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this proposed AD, the regulatory evaluation, any comments received, and other information. The street address for the Docket Operations office (telephone [phone]) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT:

Mike Borfitz, Aerospace Engineer, International Branch, ANM-116, FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to send any written relevant data, views, or arguments about this proposed AD. Send your comments to an address listed under the ADDRESSES section. Include “Docket No. FAA-2008-0299; Directorate Identifier 2007-NM-254-AD” at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this proposed AD. We will consider all comments received by the closing date and may amend this proposed AD based on those comments.

We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact we receive about this proposed AD.

Discussion

The Civil Aviation Authority of Israel (CAAI), which is the aviation authority for Israel, has issued Israeli Airworthiness Directive 55-07-06-07R1, dated June 26, 2007 (referred to after this as “the MCAI”), to correct an unsafe condition for the specified products. The MCAI states:

Two of the fasteners used to attach the “scissors” to the horizontal and the vertical stabilizers were found broken during routine maintenance. The highest loads on the “scissors” occur when using high reverse thrust. Therefore, the reverse thrust must be limited to idle in order to keep the loads at a sufficiently low level to preclude any structural problem. It was established that on model 1125 Astra, alternate fasteners of inferior strength were sometimes installed. When the originally specified fasteners are installed, the limitations on reverse thrust used may be lifted. For models Astra SPX and G100, however, the limitation remains in effect till further revision of this AD.

Failure of the attachment fasteners could result in possible in-flight loss of a horizontal or vertical stabilizer and consequent loss of control of the airplane. Corrective actions include revising the Airplane Flight Manual (AFM); inspections for damage of the bolts and replacing the bolt, if necessary; and doing related investigative and other corrective actions (eddy current inspection for bolt hole diameter and damage, contact Gulfstream for repair and do repair). You may obtain further information by examining the MCAI in the AD docket.

Relevant Service Information

Gulfstream has issued Alert Service Bulletin 100-55A-293, dated June 22, 2007. Gulfstream also issued Astra SPX AFM Temporary Revision (TR) No. 8, Astra AFM TR No. 15, and Gulfstream 100 AFM TR No. 1, all dated June 14, 2007; to the Astra SPX, Astra, or Gulfstream 100 AFMs, as applicable. The actions described in this service information are intended to correct the unsafe condition identified in the MCAI.

FAA's Determination and Requirements of This Proposed AD

This product has been approved by the aviation authority of another country, and is approved for operation in the United States. Pursuant to our bilateral agreement with the State of Design Authority, we have been notified of the unsafe condition described in the MCAI and service information referenced above. We are proposing this AD because we evaluated all pertinent information and determined an unsafe condition exists and is likely to exist or develop on other products of the same type design.

Differences Between This AD and the MCAI or Service Information

We have reviewed the MCAI and related service information and, in general, agree with their substance. But we might have found it necessary to use different words from those in the MCAI to ensure the AD is clear for U.S. operators and is enforceable. In making these changes, we do not intend to differ substantively from the information provided in the MCAI and related service information.

We might also have proposed different actions in this AD from those in the MCAI in order to follow FAA policies. Any such differences are highlighted in a Note within the proposed AD.

Costs of Compliance

Based on the service information, we estimate that this proposed AD would affect about 129 products of U.S. registry. We also estimate that it would take about 10 work-hours per product to comply with the basic requirements of this proposed AD. The average labor rate is $80 per work-hour. Required parts would cost about $33 per product. Where the service information lists required parts costs that are covered under warranty, we have assumed that there will be no charge for these costs. As we do not control warranty coverage for affected parties, some parties may incur costs higher than estimated here. Based on these figures, we estimate the cost of the proposed AD on U.S. operators to be $107,457, or $833 per product.

Authority for This Rulemaking

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 rulemaking action.

Regulatory Findings

We 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.

For the reasons discussed above, I certify this proposed regulation:

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 regulatory evaluation of the estimated costs to comply with this proposed AD and placed it in the AD docket.

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 FAA 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 AD:

Gulfstream Aerospace LP (Formerly Israel Aircraft Industries, Ltd.): Docket No. FAA-2008-0299; Directorate Identifier 2007-NM-254-AD.

Comments Due Date

(a) We must receive comments by April 14, 2008.

Affected ADs

(b) None.

Applicability

(c) This AD applies to Gulfstream Aerospace LP Model Astra SPX and 1125 Westwind Astra airplanes and Gulfstream 100 airplanes; certificated in any category; serial numbers 004 through 158.

Subject

(d) Air Transport Association (ATA) of America Code 55: Stabilizers.

Reason

(e) The mandatory continuing airworthiness information (MCAI) states:

Two of the fasteners used to attach the “scissors” to the horizontal and the vertical stabilizers were found broken during routine maintenance. The highest loads on the “scissors” occur when using high reverse thrust. Therefore, the reverse thrust must be limited to idle in order to keep the loads at a sufficiently low level to preclude any structural problem. It was established that on model 1125 Astra, alternate fasteners of inferior strength were sometimes installed. When the originally specified fasteners are installed, the limitations on reverse thrust used may be lifted. For models Astra SPX and G100, however, the limitation remains in effect until further revision of this AD.

Failure of the attachment fasteners could result in possible in-flight loss of a horizontal or vertical stabilizer and consequent loss of control of the airplane. Corrective actions include revising the Airplane Flight Manual (AFM); inspections for damage of the bolts and replacing the bolt, if necessary; and doing related investigative and other corrective actions (eddy current inspection for bolt hole diameter and damage, contact Gulfstream for repair and do repair).

Actions and Compliance

(f) Unless already done, do the following actions.

(1) Within 30 days after the effective date of this AD: Revise the Limitations section of the Airplane Flight Manual (AFM) by incorporating the information in the applicable Temporary Revisions (TR): Astra AFM TR No. 15; Astra SPX AFM TR No. 8; or Gulfstream 100 AFM TR No. 1; all dated June 14, 2007; into the limitations section of the Astra SPX, Astra, or Gulfstream 100 AFM, as applicable. The TRs limit the normal use of reverse thrust to idle.

Note 1:

The actions required by paragraph (f) of this AD may be done by inserting a copy of Astra AFM TR No. 15; Astra SPX AFM TR No. 8; or Gulfstream 100 AFM TR No. 1; all dated June 14, 2007; as applicable; into the limitations section of the Astra SPX, Astra, or Gulfstream 100 AFM, as applicable. When the applicable TR has been included in the general revisions of the AFM, the general revisions may be inserted in the AFM.

(2) For all airplanes: Within 25 flight hours or 30 days after the effective date of this AD, whichever comes first, do the inspections specified in paragraphs (f)(2)(i) and (f)(2)(ii) of this AD in accordance with Part A of Gulfstream Alert Service Bulletin 100-55A-293, dated June 22, 2007.

(i) Visually inspect the attachment bolts and replace any damaged bolt before further flight.

(ii) Perform a detailed visual inspection of fittings with P/N 25W357222-501-51, and fillers with P/N 25W4011001-003, and surrounding structure for damage. If blind bolts with P/N MS21141U0612 are installed and no damage is found, no further action is required. If any damage is found, before further flight, repair using a method approved in accordance with the procedures specified in paragraph (g)(2) of this AD. If any bolt with P/N AN173C11 is installed and damage is found, replace the bolt and do all related investigative and applicable corrective actions before further flight.

(3) For Model 1125 Westwind Astra airplanes (serial numbers 004, 011 through 072 inclusive, and 073 through 078 inclusive): Within 12 months after the effective date of this AD, replace all AN173C11 bolts, and do all related investigative and applicable corrective actions before further flight, as detailed in Part B of Gulfstream Alert Service Bulletin 100-55A-293, dated June 22, 2007. Accomplishment of Part B of the alert service bulletin constitutes terminating action for paragraph (f)(1) of this AD. TR No. 15 may be deleted and unlimited use of reverse thrust is allowed per the AFM.

Note 2:

Reverse thrust limitations remain in effect for Model Astra SPX and Gulfstream 100 airplanes.

FAA AD Differences

Note 3:

This AD differs from the MCAI and/or service information as follows:

Compliance Time: The compliance time required by the MCAI or service information for performing the AFM revision is immediate on receipt of this AD; however, to avoid inadvertently grounding airplanes, this AD requires performing the AFM revision within 30 days after the effective date of this AD.

Other FAA AD Provisions

(g) The following provisions also apply to this AD:

(1) Alternative Methods of Compliance (AMOCs): The Manager, International Branch, ANM-116, Transport Airplane Directorate, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. Send information to ATTN: Mike Borfitz, Aerospace Engineer, International Branch, ANM-116, FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, Washington 98057-3356; telephone [phone]; fax [phone]. Before using any approved AMOC on any airplane to which the AMOC applies, notify your appropriate principal inspector (PI) in the FAA Flight Standards District Office (FSDO), or lacking a PI, your local FSDO.

(2) Airworthy Product: For any requirement in this AD to obtain corrective actions from a manufacturer or other source, use these actions if they are FAA-approved. Corrective actions are considered FAA-approved if they are approved by the State of Design Authority (or their delegated agent). You are required to assure the product is airworthy before it is returned to service.

(3) Reporting Requirements: For any reporting requirement in this AD, under the provisions of the Paperwork Reduction Act, the Office of Management and Budget (OMB) has approved the information collection requirements and has assigned OMB Control Number 2120-0056.

Related Information

(h) Refer to MCAI CAAI Airworthiness Directive 55-07-06-07R1, dated June 26, 2007; Gulfstream Alert Service Bulletin 100-55A-293, dated June 22, 2007; and Astra SPX AFM Temporary Revision (TR) No. 8; Astra AFM TR No. 15; and Gulfstream 100 AFM TR No. 1, all dated June 14, 2007; for related information.

Issued in Renton, Washington, on March 7, 2008.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.