[Federal Register Volume 65, Number 66 (Wednesday, April 5, 2000)]
[Proposed Rules]
[Pages 17827-17829]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-8390]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2000-NM-27-AD]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 727-100 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the adoption of a new airworthiness 
directive (AD) that is applicable to certain Boeing Model 727-100 
series airplanes. This proposal would require repetitive inspections to 
detect corrosion of the lower surface of the wing center section and 
the surrounding area, and follow-on actions. This proposal is prompted 
by reports of corrosion progression through the lower surface of the 
wing center section into the center wing fuel tank, and subsequent fuel 
leakage into the ram air duct. The actions specified by the proposed AD 
are intended to detect and correct such conditions, which, if combined 
with a leak in the primary or secondary heat exchanger, could result in 
the release of fuel vapors into the cabin, and consequent adverse 
effects on flight crew and passengers.

DATES: Comments must be received by May 22, 2000.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2000-NM-27-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056. Comments may be inspected at this 
location between 9 a.m. and 3 p.m., Monday through Friday, except 
Federal holidays.
    The service information referenced in the proposed rule may be 
obtained from Boeing Commercial Airplane Group, PO 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: Stan Wood, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Transport Airplane Directorate, 1601 
Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 227-
2772; fax (425) 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 2000-NM-27-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-114, Attention: Rules 
Docket No. 2000-NM-27-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    On November 7, 1985, the FAA issued AD 85-24-02, amendment 39-5170 
(50 FR 47356, November 18, 1985), applicable to all Boeing Model 727-
200 series airplanes, which requires repetitive inspections for 
corrosion, and repair, as necessary, of the lower surface of the wing 
center section, which forms the upper wall of the ram air plenum 
chambers.
    Since the issuance of that AD, the manufacturer has notified the 
FAA that certain airplanes were inadvertently not included in the 
effectivity listing in Boeing Service Bulletin 727-51-17, dated April 
26, 1974, which was referenced as the appropriate source of service 
information for accomplishment of the actions required by AD 85-24-02. 
That service bulletin describes corrosion inspections for Model 727-200 
series airplanes having integral fuel cells installed. Model 727-100 
series airplanes were not included in the effectivity of that service 
bulletin, and consequently, in the applicability of the existing AD, 
due to the fact that bladder-type fuel cells are installed on the 
majority of those airplanes. However, it has now been determined that 
there are three Model 727-100 series airplanes having integral fuel 
cells installed that are subject to the same unsafe condition as the 
airplanes that are included in the applicability statement of AD 85-24-
02. Therefore, the FAA finds that additional rulemaking is necessary to 
ensure that the unsafe condition is addressed on all affected 
airplanes.

[[Page 17828]]

Explanation of Relevant Service Information

    The FAA has reviewed and approved Boeing Service Bulletin 727-51-
17, Revision 1, dated January 24, 1986, which describes procedures for 
repetitive inspections to detect corrosion of the lower surface of the 
wing center section and the surrounding area, and follow-on actions. 
The follow-on actions consist of the application of corrosion-
inhibiting compound and repair of any corrosion. Accomplishment of the 
actions described in the service bulletin is intended to adequately 
address the identified unsafe condition.

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 accomplishment of the actions specified in 
the service bulletin described previously, except as discussed below.

Difference Between Proposed Rule and Service Bulletin

    Operators should note that Revision 1 of the service bulletin (as 
well as the original issue of the service bulletin, which was 
referenced as the appropriate source of service information for 
accomplishment of the actions required by AD 85-24-02), specifies the 
effectivity of that service bulletin as, ``all Model 727-200 series 
airplanes.'' However, the manufacturer has informed the FAA that it has 
identified three Model 727-100 series airplanes that were inadvertently 
not included in the effectivity listing and have not accomplished the 
actions required by that AD. Therefore, the applicability section of 
this proposed rule specifies only those airplanes (described as Group 1 
airplanes in the service bulletin).
    Operators also should note that, although the service bulletin 
specifies that the manufacturer may be contacted for disposition of 
certain corrosion repair conditions, this proposal would require the 
repair of those conditions to be accomplished in accordance with a 
method approved by the FAA.

Cost Impact

    There are 3 Model 727-100 series airplanes of the affected design 
in the worldwide fleet. The FAA estimates that 2 airplanes of U.S. 
registry would be affected by this proposed AD, that it would take 
approximately 12 work hours per airplane to accomplish the proposed 
inspection, and that the average labor rate is $60 per work hour. Based 
on these figures, the cost impact of the proposed AD on U.S. operators 
is estimated to be $1,440, or $720 per airplane, per inspection cycle.
    The cost impact figure discussed above is based on assumptions that 
no operator has yet accomplished any of 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 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. Therefore, it 
is determined that this proposal would not have federalism implications 
under Executive Order 13132.
    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 2000-NM-27-AD.

    Applicability: Model 727-100 series airplanes, serial numbers 
20512, 20513, and 20533; 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 (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 detect corrosion of the lower surface of the wing center 
section and the surrounding area, and subsequent fuel leakage into 
the ram air duct, which, if combined with a leak in the primary or 
secondary heat exchanger, could result in the release of fuel vapors 
into the cabin, and consequent adverse effects on flight crew and 
passengers, accomplish the following:

Detailed Visual Inspection

    (a) Within 1 year or 3,000 hours time-in-service after the 
effective date of this AD, whichever occurs first: Perform a 
detailed visual inspection in accordance with Part II.B. of the 
Accomplishment Instructions of Boeing Service Bulletin 727-51-17, 
Revision 1, dated January 24, 1986. Repeat the inspection thereafter 
at intervals not to exceed 4 years or 8,000 hours time-in-service, 
whichever occurs first.

    Note 2: For the purposes of this AD, a detailed visual 
inspection is defined as: ``An intensive visual examination of a 
specific structural area, system, installation, or assembly to 
detect damage, failure, or irregularity. Available lighting is 
normally supplemented with a direct source of good lighting at 
intensity deemed appropriate by the inspector. Inspection aids such 
as mirror, magnifying lenses, etc., may be used. Surface cleaning 
and elaborate access procedures may be required.''

Follow-On Actions

    (1) If no corrosion is detected, prior to further flight, apply 
corrosion inhibiting compound in accordance with Part II.C. of the 
Accomplishment Instructions of the service bulletin.
    (2) If any corrosion is detected, prior to further flight, 
repair in accordance with Part II.D. of the Accomplishment 
Instructions of the service bulletin; or in accordance with a method 
approved by the Manager, Seattle Aircraft Certification Office 
(ACO), FAA, Transport Airplane Directorate.

Alternative Methods of Compliance

    (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 ACO. 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.


[[Page 17829]]


    Note 3: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Seattle ACO.

Special Flight Permit

    (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 March 30, 2000.
Donald L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 00-8390 Filed 4-4-00; 8:45 am]
BILLING CODE 4910-13-U