AD 98-08-09

This document publishes in the Federal Register an amendment adopting Airworthiness Directive (AD) 98-08-09 that was sent previously to all known U.S. owners and operators of certain Lockheed Model L-1011-385 series airplanes by individual notices. This AD requires revision of the Airplane Flight Manual (AFM) to prohibit operation of the fuel boost pumps when fuel quantities are below certain levels, and to add new maintenance procedures for operating the airplane with an inoperative fuel boost pump assembly or with an inoperative flight station fuel quantity indicating system. This AD also requires the installation of a placard on the engineer's fuel panel to advise the maintenance crew that operation of the fuel boost pumps when less than 1,200 pounds of fuel are in the corresponding wing fuel tank is prohibited. This action is prompted by reports of internal electrical failures in the fuel boost pump of the wing fuel tanks that could result in either electrical arcing or localized overheating. The actions specified by this AD are intended to prevent such electrical arcing or overheating, which could breech the protective housing of the fuel boost pump and expose it to fuel vapors and fumes, and consequent potential fire or explosion in the wing fuel tank.

Final rule; request for comments.

98-08-09 LOCKHEED AERONAUTICAL SYSTEMS COMPANY: Amendment 39-10492. Docket 98-NM-125-AD.

Applicability: Model L-1011-385-1, -385-1-14, -385-1-15, and -385-3 series airplanes, certificated in any category.

NOTE 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (c) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.

Compliance: Required as indicated, unless accomplished previously.

To prevent a potential fire or explosion in the wing fuel tank, accomplish the following:

(a) Within 50 flight hours or 10 days after the effective date of this AD, whichever occurs first, revise the Limitations and Procedures Sections of the FAA-approved Airplane Flight Manual (AFM) to include the following information. This may be accomplished by inserting a copy of this AD into the AFM.

Add to Limitations Section:

"FUEL SYSTEM

Fuel Pumps

Do not operate the fuel boost pumps of the affected wing tank in the air or on the ground when fuel quantities are less than the following:

Wing tanks 1 and 3: Less than 1,200 lbs (545 kg) in each tank.

Wing tanks 2L and 2R: Less than 1,200 lbs (545 kg) total in the two compartments (inboard and outboard) of each tank.

These quantities should be considered unusable fuel for the purposes of fuel management.

When operating with a fuel boost pump assembly inoperative per Master Minimum Equipment List (MMEL) item number 28-24-01, add the following maintenance procedure:

Pull and collar the affected circuit breaker.

When operating with an inoperative flight station fuel quantity indicating system per MMEL item 28-41-00, do not operate the fuel boost pumps of the affected wing tank in the air or on the ground when fuel quantities are less than the following:

Wing tanks 1 and 3: Less than 7,000 lbs (3,175 kg) in the affected tank.

Wing tanks 2L and 2R: Less than 1,200 lbs (545 kg) total in the two compartments (inboard and outboard) of the affected tank."

Add to Procedures Section:

"FUEL SYSTEM

Fuel Pumps

If the circuit breaker for any wing tank fuel boost pump (circuit breakers U3, U4, U7, U8, U9, U10, U13, U14) trips, do not reset. If the pump trips while in flight, continue flight in accordance with the procedures in the "Tank Pumps LOW Lights On" portion of the Procedures section of the AFM. If the breaker trips while on the ground, do not reset without first identifying the source of the electrical fault.

ELECTRICAL SYSTEM

Fuel Pumps

If the circuit breaker for any wing tank fuel boost pump (circuit breakers U3, U4, U7, U8, U9, U10, U13, U14) trips, do not reset. If the pump trips while in flight, continue flight in accordance with the procedures in the "Tank Pumps LOW Lights On" portion of the Procedures section of the AFM. If the breaker trips while on the ground, do not reset without first identifying the source of the electrical fault."

(b) Within 50 flight hours or 10 days after the effective date of this AD, whichever occurs first, install a placard on the engineer's fuel panel that states:

"If FQIS is operative, do not operate the fuel boost pumps when less than 1,200 pounds of fuel are in the corresponding wing tanks."

(c) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Atlanta Aircraft Certification Office (ACO), FAA, Small Airplane Directorate. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Atlanta ACO.

NOTE 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Atlanta ACO.

(d) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished.

(e) This amendment becomes effective on April 28, 1998, to all persons except those persons to whom it was made immediately effective by emergency AD 98-08-09, issued on April 3, 1998, which contained the requirements of this amendment.

On April 3, 1998, the FAA issued emergency AD 98-08-09, which is applicable to certain Lockheed Model L-1011-385 series airplanes.

The FAA has received reports of internal electrical failures in the fuel boost pump of the wing fuel tanks that could result in either electrical arcing or localized overheating. Such electrical arcing or overheating could burn a hole in the pump housing and the protective housing of the fuel boost pump. If electrical arcing or overheating breeches the protective housing and the fuel in the wing fuel tank is at a sufficient level, the liquid fuel would prevent combustion. However, if electrical arcing or overheating breeches the protective housing of the fuel boost pump and the fuel level of the wing tank is low enough to expose the protective housing to fuel vapors and fumes, a potential fire or explosion could occur. The on-going investigation of the internal electrical failures has not revealed the cause of the failures as yet.

Explanation of Requirements of the Rule
Since the unsafe condition described is likely to exist or develop on other airplanes of the same type design, the FAA issued emergency AD 98-08-09 to prevent a potential fire or explosion in the wing fuel tank due to exposure of the fuel boost pump to fuel vapors and fumes. The AD requires revision of the Limitations and Procedures Sections of the FAA-approved Airplane Flight Manual (AFM) to prohibit operation of the fuel boost pumps when fuel quantities are below certain levels, and to add new maintenance procedures for operating the airplane with an inoperative fuel boost pump assembly or with an inoperative flight station fuel quantity indicating system (FQIS). The AD also requires the installation of a placard on the engineer's fuel panel to advise the maintenance crew that operation of the fuel boost pumps when less than 1,200 pounds of fuel are in the corresponding wing fuel tank is prohibited.

This is considered tobe interim action until final action is identified, at which time the FAA may consider further rulemaking.

Since it was found that immediate corrective action was required, notice and opportunity for prior public comment thereon were impracticable and contrary to the public interest, and good cause existed to make the AD effective immediately by individual notices issued to all known U.S. owners and operators of certain Lockheed Model L-1011-385 series airplanes. These conditions still exist, and the AD is hereby published in the Federal Register as an amendment to section 39.13 of the Federal Aviation Regulations (14 CFR 39.13) to make it effective to all persons.

Comments Invited
Although this action is in the form of a final rule that involves requirements affecting flight safety and, thus, was not preceded by notice and an opportunity for public comment, comments are invited on this rule. Interested persons are invited to comment on this rule by submitting such written data, views, or arguments as they may desire. Communications shall identify the Rules Docket number and be submitted in triplicate to the address specified under the caption "ADDRESSES." All communications received on or before the closing date for comments will be considered, and this rule may be amended in light of the comments received. Factual information that supports the commenter's ideas and suggestions is extremely helpful in evaluating the effectiveness of the AD action and determining whether additional rulemaking action would be needed.

Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the rule that might suggest a need to modify the rule. All comments submitted will be available, both before and after the closing date for comments, in the Rules Docket for examination by interested persons. A report that summarizes each FAA-public contact concerned with the substance of this AD will be filed in the RulesDocket.

Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this rule must submit a self-addressed, stamped postcard on which the following statement is made: "Comments to Docket Number 98-NM-125-AD." The postcard will be date stamped and returned to the commenter. Regulatory Impact

The regulations adopted herein will not have substantial direct effects 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. Therefore, in accordance with Executive Order 12612, it is determined that this final rule does not have sufficient federalism implications to warrant the preparation of a Federalism Assessment.

The FAA has determined that this regulation is an emergency regulation that must be issued immediately to correct an unsafe condition in aircraft, and that it is not a "significant regulatory action" under Executive Order 12866. It has been determined further that this action involves an emergency regulation under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979). If it is determined that this emergency regulation otherwise would be significant under DOT Regulatory Policies and Procedures, a final regulatory evaluation will be prepared and placed in the Rules Docket. A copy of it, if filed, may be obtained from the Rules Docket at the location provided under the caption "ADDRESSES."

List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Safety.

Adoption of the Amendment
Accordingly, pursuant to 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. Section 39.13 is amended by adding the following new airworthiness directive: