2011-15536. Airworthiness Directives; The Boeing Company Model 747SP Series 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 would require replacing or modifying the upper and lower rudder power control modules (PCM). This proposed AD was prompted by a report of a rudder hard-over event on a Model 747-400 series airplane, caused by a rudder PCM manifold cracking and separating in the area of the yaw damper cavity end-cap. We are proposing this AD to prevent a failure of the lower or upper rudder PCM manifold, which could result in a hard-over of the rudder surface leading to an increase in pilot workload and a possible high-speed runway excursion upon landing.

DATES:

We must receive comments on this proposed AD by August 8, 2011.

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: Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

For service information identified in this proposed AD, contact Boeing Commercial Airplanes, Attention: Data & Services Management, P.O. Box 3707, MC 2H-65, Seattle, Washington 98124-2207; telephone [phone], extension 1; fax [phone]; e-mail [e-mail]; Internet https://www.myboeingfleet.com. You may review copies of the referenced service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington. For information on the availability of this material at the FAA, call 425-227-1221.

Examining the AD Docket

You may examine the AD docket on the Internet at http://www.regulations.gov;​; or in person at the Docket Management Facility 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 Office (phone: [phone]) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT:

Marie Hogestad, Aerospace Engineer, Systems and Equipment Branch, ANM-130S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; phone: [phone]; fax: [phone]; e-mail: [e-mail].

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to send any written relevant data, views, or arguments about this proposal. Send your comments to an address listed under the ADDRESSES section. Include “Docket No. FAA-2011-0571; Directorate Identifier 2010-NM-263-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 because of 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

We received a report from an operator of a Model 747-400 series airplane of a lower rudder hard-over event caused by a lower rudder PCM manifold cracking and separating in the area of the yaw damper cavity end-cap. This allowed the yaw damper sleeve to shift, giving the system a lower rudder left input (beyond the yaw damper authority). Yaw damper authority is limited to +/− 4 degrees of rudder command. The failure removed the yaw damper end stop and allowed the yaw damper input to exceed the maximum design yaw damper authority. Although commanding full retract, pilot pedal inputs were ineffective in moving the lower rudder back to the right. We also received three additional reports of cracking in the rudder PCM manifold. These events did not result in a hard-over, but created the need for a retention feature solution specified in AD 2008-13-03, Amendment 39-15566, for Model 747-400, -400D, and -400F series airplanes. Upon investigation, it was determined that the Model 747SP fleet could be susceptible to the same failure because they use the same manifold sub-assembly as the Model 747-400 series airplanes. Cracking in a rudder PCM manifold, if not corrected, could result in a failure of the upper or lower rudder PCM manifold, which could result in a hard-over of the rudder surface leading to an increase in pilot workload and a possible high-speed runway excursion upon landing.

Relevant Service Information

We reviewed Boeing Alert Service Bulletin 747-27A2497, dated September 30, 2010. The service information describes procedures for either replacing the upper and lower rudder PCMs having Boeing part number (P/N) 60B80093-3 (Parker P/N 241700-1005) or Boeing P/N 60B80093-4 (Parker P/N 241700-1007), with new rudder PCMs having Boeing P/N 60B80093-104 (Parker P/N 241700-9007); or modifying the upper and lower rudder PCMs having Boeing P/N 60B80093-3 (Parker P/N 241700-1005) or Boeing P/N 60B80093-4 (Parker P/N 241700-1007) by replacing the access cap with a two piece cap that includes a retention feature for the yaw damper modulating piston assembly in the rudder PCM.

Boeing Alert Service Bulletin 747-27A2497, dated September 30, 2010, refers to Parker Service Bulletin 241700-27-333, dated January 26, 2010, as an additional source of guidance for modifying the upper and lower rudder PCMs provided in Option 2 of Work Packages 1 and 2 of Boeing Alert Service Bulletin 747-27A2497, dated September 30, 2010.

FAA's Determination

We are proposing this AD because we evaluated all the relevant information and determined the unsafe condition described previously is likely to exist or develop in other products of the same type designs.

Proposed AD Requirements

This proposed AD would require accomplishing the actions specified in the service information described previously.

Costs of Compliance

We estimate that this proposed AD affects 7 airplanes of U.S. registry.

We estimate the following costs to comply with this proposed AD:

Estimated Costs

Action	Labor cost	Parts cost	Cost per product	Cost on U.S. operators
Replace rudder PCM (P/N 241700-1007)	11 work-hours × $85 per hour = $935	$5,856	$6,791	$47,537
Replace rudder PCM (P/N 241700-1005)	11 work-hours × $85 per hour = $935	8,568	9,503	66,521
Modify rudder PCM (P/N 241700-1007)	3 work-hours × $85 per hour = $255	1,374	1,629	11,403
Modify rudder PCM (P/N 241700-1005)	3 work hours × $85 per hour = $255	4,086	4,341	30,387

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),

(3) Will not affect intrastate aviation in Alaska, and

(4) 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.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Incorporation by reference
• 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 airworthiness directive (AD):

The Boeing Company: Docket No. FAA-2011-0571; Directorate Identifier 2010-NM-263-AD.

Comments Due Date

(a) We must receive comments by August 8, 2011.

Affected ADs

(b) None.

Applicability

(c) This AD applies to all The Boeing Company Model 747SP series airplanes, certificated in any category.

Subject

(d) Joint Aircraft System Component (JASC)/Air Transport Association (ATA) of America Code 27, Flight Controls.

Unsafe Condition

(e) This AD was prompted by a report of a rudder hard-over event on a Model 747-400 series airplane, caused by a rudder power control module (PCM) manifold cracking and separating in the area of the yaw damper cavity end-cap. We are issuing this AD to prevent a failure of the lower or upper rudder PCM manifold, which could result in a hard-over of the rudder surface leading to an increase in pilot workload and a possible high-speed runway excursion upon landing.

Compliance

(f) Comply with this AD within the compliance times specified, unless already done.

Replace or Modify Rudder PCMs

(g) Within 24 months or 8,400 flight hours after the effective date of this AD, whichever occurs first, do the replacement specified in paragraph (g)(1) of this AD or the modification specified in paragraph (g)(2) of this AD for the upper and lower rudder PCMs, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 747-27A2497, dated September 30, 2010.

(1) Replace any rudder PCM having Boeing part number (P/N) 60B80093-3 (Parker P/N 241700-1005) or Boeing P/N 60B80093-4 (Parker P/N 241700-1007) with rudder PCM having Boeing P/N 60B80093-104 (Parker P/N 241700-9007).

(2) Modify the rudder PCM having Boeing P/N 60B80093-3 (Parker P/N 241700-1005) or Boeing P/N 60B80093-4 (Parker P/N 241700-1007).

Note 1:

Boeing Alert Service Bulletin 747-27A2497, dated September 30, 2010, refers to Parker Service Bulletin 241700-27-333, dated January 26, 2010, as an additional source of guidance for modifying the upper and lower rudder PCM manifold access caps provided in Option 2 of Work Packages 1 and 2 of Boeing Alert Service Bulletin 747-27A2497, dated September 30, 2010.

Parts Installation

(h) As of the effective date of this AD, no person may install a rudder PCM having Boeing P/N 60B80093-3 (Parker P/N 241700-1005) or Boeing P/N 60B80093-4 (Parker P/N 241700-1007), on any airplane.

Alternative Methods of Compliance (AMOCs)

(i)(1) The Manager, Seattle Aircraft Certification Office (ACO), FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request to your principal inspector or local Flight Standards District Office, as appropriate. If sending information directly to the manager of the ACO, send it to the attention of the person identified in the Related Information section of this AD. Information may be e-mailed to: [e-mail].

(2) Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the local flight standards district office/certificate holding district office.

Related Information

(j) For more information about this AD, contact Marie Hogestad, Aerospace Engineer, Systems and Equipment Branch, ANM-130S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone: [phone]; fax: [phone]; e-mail: [e-mail].

(k) For service information identified in this AD, contact Boeing Commercial Airplanes, Attention: Data & Services Management, P.O. Box 3707, MC 2H-65, Seattle, Washington 98124-2207; telephone [phone], extension 1; fax [phone]; e-mail [e-mail]; Internet https://www.myboeingfleet.com. You may review copies of the referenced service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington. For information on the availability of this material at the FAA, call 425-227-1221.

Issued in Renton, Washington on June 14, 2011.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.