E8-13920. Airworthiness Directives; Boeing Model 727 Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

We propose to adopt a new airworthiness directive (AD) for certain Boeing Model 727 airplanes. This proposed AD would require performing an operational test of the engine fuel suction feed of the fuel system, and other related testing if necessary. This proposed AD results from a report of in-service occurrences of loss of fuel system suction feed capability, followed by total loss of pressure of the fuel feed system. We are proposing this AD to detect and correct failure of the engine fuel suction feed of the fuel system, which could result in multi-engine flameout, inability to restart the engines, and consequent forced landing of the airplane.

DATES:

We must receive comments on this proposed AD by August 4, 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 W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

For service information identified in this AD, contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207.

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 (telephone [phone]) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT:

Sue Lucier, Aerospace Engineer, Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification Office, 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-2008-0646; Directorate Identifier 2007-NM-359-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 have received a report of in-service occurrences of loss of fuel system suction feed capability, followed by total loss of pressure of the fuel feed system. This report prompted us to review the service history of all Boeing airplane models, and we found instances of loose and leaking fuel line fittings. This condition, if not corrected, could result in multi-engine flameout, inability to restart the engines, and consequent forced landing of the airplane.

Explanation of Relevant Service Information

We have reviewed Boeing Service Bulletin 727-28-80, dated June 21, 1985. The service bulletin describes procedures for performing an operational test of the engine fuel suction feed of the fuel system, and other related testing if necessary. The other related testing includes doing a vacuum test on the applicable engine for leakage if an engine's N1, N2, or fuel-flow parameters deteriorate during the test. If any leakage is found the corrective actions include inspecting and repairing or replacing any leaking Gamah fittings with new fittings, and inspecting and repairing any major welded tube assemblies that are leaking.

FAA's Determination and Requirements of This Proposed AD

We are proposing this AD because we have evaluated all pertinent information and identified an unsafe condition that is likely to exist or develop on other airplanes of this same type design. For this reason, we are proposing this AD, which would require accomplishing the actions specified in the service information described previously, except as discussed under “Differences Between the Proposed AD and Service Information.”

Differences Between the Proposed AD and Service Information

The service bulletin recommends accomplishing the initial operational test “at the next regularly scheduled C-check following accumulation of 20,000 total flight hours or seven years age,” we have determined that this imprecise compliance time would not address the identified unsafe condition in a timely manner. In developing an appropriate compliance time for this AD, we considered not only the manufacturer's recommendation, but the degree of urgency associated with addressing the subject unsafe condition, the average utilization of the affected fleet, and the time necessary to perform the modifications. In light of all of these factors, we find a compliance time of 7,000 flight hours for completing the required actions to be warranted, in that it represents an appropriate interval of time for affected airplanes to continue to operate without compromising safety. This difference has been coordinated with Boeing.

Part II of the Accomplishment Instructions of the service bulletin specifies that operators may accomplish the other specified actions (a vacuum test of the fuel feed system) using an operator's equivalent procedure (with substitute test equipment). However, this proposed AD would require operators to accomplish the actions using the procedures specified in Figure 4 of the service bulletin. An “operator's equivalent procedure” may be used only if approved as an alternative method of compliance according to paragraph (h) of this AD.

Costs of Compliance

We estimate that this proposed AD would affect 709 airplanes of U.S. registry. We also estimate that it would take 1 work-hour per product, per test, to comply with this proposed AD. The average labor rate is $80 per work-hour. Based on these figures, we estimate the cost of this proposed AD to the U.S. operators to be $56,720, or $80 per product, per test.

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.

You can find our regulatory evaluation and the estimated costs of compliance 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:

Boeing: Docket No. FAA-2008-0646; Directorate Identifier 2007-NM-359-AD.

Comments Due Date

(a) We must receive comments by August 4, 2008.

Affected ADs

(b) None.

Applicability

(c) This AD applies to Boeing Model 727, 727C, 727-100, 727-100C, 727-200, and 727-200F series airplanes, certificated in any category.

Unsafe Condition

(d) This AD results from a report of in-service occurrences of loss of fuel system suction feed capability, followed by total loss of pressure of the fuel feed system. We are issuing this AD to detect and correct failure of the engine fuel suction feed of the fuel system, which could result in multi-engine flameout, inability to restart the engines, and consequent forced landing of the airplane.

Compliance

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

Operational Test/Other Specified Actions

(f) Within 7,000 flight hours after the effective date of this AD, perform an operational test of the engine fuel suction feed of the fuel system, and perform all other related testing, as applicable, before further flight, in accordance with the Accomplishment Instructions of Boeing Service Bulletin 727-28-80, dated June 21, 1985. Repeat the operational test thereafter at intervals not to exceed 7,000 flight hours.

Operator's Equivalent Procedure

(g) If any discrepancy is found, and Boeing Service Bulletin 727-28-80, dated June 21, 1985, specifies that certain actions (i.e., a vacuum test of the fuel feed system) may be accomplished using an operator's “equivalent procedure” (with substitute test equipment): The actions must be accomplished in accordance with Figure 4 of the service bulletin.

Alternative Methods of Compliance (AMOCs)

(h)(1) The Manager, Seattle ACO, FAA, ATTN: Sue Lucier, Aerospace Engineer, Propulsion Branch, ANM-140S, FAA, Seattle ACO, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone [phone]; fax [phone], has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19.

(2) To request a different method of compliance or a different compliance time for this AD, follow the procedures in 14 CFR 39.19. 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.

Issued in Renton, Washington, on June 9, 2008.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.