[Federal Register Volume 61, Number 119 (Wednesday, June 19, 1996)]
[Proposed Rules]
[Pages 31061-31063]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-15604]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
14 CFR Part 39
[Docket No. 95-NM-106-AD]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 727 and 737 Series
Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Notice of proposed rulemaking (NPRM).
-----------------------------------------------------------------------
SUMMARY: This document proposes the adoption of a new airworthiness
directive (AD) that is applicable to certain Boeing Model 727 and 737
series airplanes. This proposal would require replacing the fuel cap
assembly with a new assembly on the inlet fitting at the inside top of
the auxiliary fuel tank. The proposal would also require replacing the
INOP placards with new placards. This proposal is prompted by reports
that the fuel cap assembly, due to its design, became loose and allowed
fuel to enter the deactivated auxiliary fuel tanks on in-service
airplanes. The actions specified by the proposed AD are intended to
prevent unwanted fuel transferring to the deactivated auxiliary fuel
tanks, due to the problems associated with a loose fuel cap assembly.
DATES: Comments must be received by July 29, 1996.
[[Page 31062]]
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 95-NM-106-AD, 1601 Lind Avenue, SW.,
Renton, Washington 98055-4056. Comments may be inspected at this
location between 9:00 a.m. and 3:00 p.m., Monday through Friday, except
Federal holidays.
The service information referenced in the proposed rule may be
obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle,
Washington 98124-2207. This information may be examined at the FAA,
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton,
Washington.
FOR FURTHER INFORMATION CONTACT: Sulmo Mariano, Aerospace Engineer,
Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification
Office, 1601 Lind Avenue, SW., Renton, Washington; telephone (206) 227-
2686; fax (206) 227-1181.
SUPPLEMENTARY INFORMATION:
Comments Invited
Interested persons are invited to participate in the making of the
proposed 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 above. All
communications received on or before the closing date for comments,
specified above, will be considered before taking action on the
proposed rule. The proposals contained in this notice may be changed in
light of the comments received.
Comments are specifically invited on the overall regulatory,
economic, environmental, and energy aspects of the proposed 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 summarizing each FAA-public contact concerned with
the substance of this proposal will be filed in the Rules Docket.
Commenters wishing the FAA to acknowledge receipt of their comments
submitted in response to this notice must submit a self-addressed,
stamped postcard on which the following statement is made: ``Comments
to Docket Number 95-NM-106-AD.'' The postcard will be date stamped and
returned to the commenter.
Availability of NPRMs
-Any person may obtain a copy of this NPRM by submitting a request
to the FAA, Transport Airplane Directorate, ANM-103, Attention: Rules
Docket No. 95-NM-106-AD, 1601 Lind Avenue, SW., Renton, Washington
98055-4056.
Discussion
On October 31, 1980, the FAA issued AD 80-02-01 R2, amendment 39-
3969 (45 FR 74467, November 10, 1980), applicable to Boeing Model 727
series airplanes on which an operative Boeing-designed auxiliary body
fuel system is installed. In addition, the FAA issued a similar AD 80-
02-02 R2, amendment 39-3970 (45 FR 74467, November 10, 1980), which is
applicable to Boeing Model 737 series airplanes on which an operative
Boeing-designed auxiliary body fuel system is installed. Those ADs were
prompted by reports of loss of fuel from the auxiliary body fuel tank
due to defective and damaged shrouds. The actions required by those
AD's are intended to prevent failure of the fuel system and unwanted
fuel transfer to the auxiliary body fuel tanks.
Events Since Issuance of Previous AD's
Since issuance of those AD's, the FAA has received reports
indicating that, on certain Boeing Model 727 series airplanes, the fuel
cap assembly (which was installed to deactivate the auxiliary fuel
tanks, in accordance with AD 80-02-01 R2) became loose and allowed fuel
to enter the tanks. Investigation revealed that, due to incorrect
procedures that were provided in the relevant service bulletin, the
safety lockwire of the fuel cap assembly was attached to the cap,
rather than to the nut. This condition, if not corrected, could allow
the nut of the fuel cap assembly to back off and the cap to loosen;
consequently, unwanted fuel could then transfer to the auxiliary fuel
tanks.
The fuel cap assembly on certain Model 737 series airplanes is
identical to that on the affected Model 727 series airplanes.
Therefore, those Model 737 series airplanes may be subject to this same
unsafe condition revealed on the Model 727 series airplanes.
Explanation of Relevant Service Information
The FAA has reviewed and approved Boeing Alert Service Bulletin
727-28A0062, Revision 5, dated May 4, 1995 (for Model 727 series
airplanes) and Boeing Alert Service Bulletin 737-28A1032, Revision 2,
dated May 4, 1995 (for Model 737 series airplanes). For airplanes
equipped with forward and/or aft auxiliary fuel tanks that have been
deactivated, these service bulletins contain:
1. Procedures for replacing the fuel cap assembly having part
number (P/N) AN929A24 with a new fuel cap assembly having P/N AN929L24
on the inlet fitting at the inside top of the auxiliary fuel tank; and
2. procedures for replacing the INOP placards with new placards,
which state that the fuel indicators for the auxiliary fuel tanks are
still operational.
For certain other airplanes listed in these service bulletins, no
additional work is necessary.
Explanation of Requirements of Proposed Rule
Since an unsafe condition has been identified that is likely to
exist or develop on other products of this same type design, the
proposed AD would require replacing the fuel cap assembly with a new
assembly on the inlet fitting at the inside top of the auxiliary fuel
tank. The proposed AD also would require replacing the INOP placards
with new placards; these replacement actions would be required only on
airplanes on which the auxiliary fuel tank has been deactivated. The
actions would be required to be accomplished in accordance with the
service bulletins described previously.
Cost Impact
There are approximately 211 Boeing Model 727 series airplanes and
36 Boeing Model 737 series airplanes of the affected design in the
worldwide fleet. The FAA estimates that 134 Boeing Model 727 series
airplanes and 25 Boeing Model 737 series airplanes of U.S. registry may
be affected by this proposed AD, depending on the current configuration
of the airplanes.
For Boeing Model 727 series airplanes, the proposed modification
would take approximately 53 work hours per airplane to accomplish, at
an average labor rate of $60 per work hour. Required parts would be
supplied by the manufacturer at no cost to the operators. Based on
these figures, the cost impact of the proposed AD on U.S. operators is
estimated to be $3,180 per airplane.
For Boeing Model 737 series airplanes, the proposed modification
would take approximately 18 work hours per airplane to accomplish, at
an average labor rate of $60 per work hour. Required parts would be
supplied by the manufacturer at no cost to the operators. Based on
these figures, the cost impact of the proposed AD on U.S. operators is
estimated to be $1,080 per airplane.
The cost impact figures discussed above are based on assumptions
that no operator has yet accomplished any of
[[Page 31063]]
the proposed requirements of this AD action, and that no operator would
accomplish those actions in the future if this AD were not adopted.
Regulatory Impact
The regulations proposed herein would 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
proposal would not have sufficient federalism implications to warrant
the preparation of a Federalism Assessment.
For the reasons discussed above, I certify that 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) if promulgated, 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. A copy of the draft
regulatory evaluation prepared for this action is contained in the
Rules Docket. A copy of it may be obtained by contacting 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.
The Proposed Amendment
Accordingly, pursuant to the authority delegated to me by the
Administrator, the Federal Aviation Administration proposes to amend
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.
Sec. 39.13 [Amended]
2. Section 39.13 is amended by adding the following new
airworthiness directive:
Boeing: Docket 95-NM-106-AD.
Applicability: Model 727 and 737 airplanes equipped with forward
and/or aft auxiliary fuel tanks that have been deactivated,
certificated in any category.
Note 1: This AD applies to each airplane identified in the
preceding applicability provision, regardless of whether it has been
otherwise 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 (b) 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 the nut of the fuel cap assembly from backing off and
the cap from loosening, and subsequently, unwanted fuel transferring
to the auxiliary fuel tanks, accomplish the following:
(a) Within 6 months after the effective date of this AD,
accomplish paragraphs (a)(1) and (a)(2) of this AD, in accordance
with Part IV of the Accomplishment Instructions of Boeing Service
Bulletin 727-28A0062, Revision 5, dated May 4, 1995 (for Model 727
series airplanes), or Boeing Service Bulletin 737-28A1032, Revision
2, dated May 4, 1995 (for Model 737 series airplanes), as
applicable.
(1) Replace the fuel cap assembly having part number (P/N)
AN929A24 with a new fuel cap assembly having P/N AN929L24 on the
inlet fitting at the inside top of the auxiliary fuel tank, in
accordance with the applicable service bulletin. And
(2) Replace the INOP placards with new placards, in accordance
with the applicable service bulletin.
(b) 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, Seattle Aircraft Certification
Office (ACO), FAA, Transport 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, Seattle ACO.
Note 2: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Seattle ACO.
(c) 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.
Issued in Renton, Washington, on June 13, 1996.
James V. Devany,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 96-15604 Filed 6-18-96; 8:45 am]
BILLING CODE 4910-13-U
