[Federal Register Volume 64, Number 193 (Wednesday, October 6, 1999)]
[Proposed Rules]
[Pages 54246-54248]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-26089]
[[Page 54246]]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 99-NM-75-AD]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 727 Series Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Notice of proposed rulemaking (NPRM).
-----------------------------------------------------------------------
SUMMARY: This document proposes the supersedure of an existing
airworthiness directive (AD), applicable to certain Boeing Model 727
series airplanes, that currently requires repetitive inspections to
detect cracking of the rear spar web or fuel leakage of the wing center
section, and repair, if necessary. That action also provides for an
optional modification of the rear spar web that constitutes terminating
action for the repetitive inspections. That action was prompted by
several reports of fuel leakage due to cracking of the rear spar web of
the wing center section. This action would require accomplishment of
the previously optional terminating action. The actions specified by
the proposed AD are intended to prevent cracking of the rear spar web,
which could permit fuel leakage into the airflow multiplier, and could
result in an electrical short that could cause a fire.
DATES: Comments must be received by November 22, 1999.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-114,
Attention: Rules Docket No. 99-NM-75-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: Walter Sippel, Aerospace Engineer,
Airframe Branch, ANM-120S, FAA, Transport Airplane Directorate, Seattle
Aircraft Certification Office, 1601 Lind Avenue, SW., Renton,
Washington 98055-4056; telephone (425) 227-2774; 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 99-NM-75-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. 99-NM-75-AD, 1601 Lind Avenue, SW., Renton, Washington
98055-4056.
Discussion
On December 3, 1997, the FAA issued AD 97-25-15, amendment 39-10239
(62 FR 65355, December 12, 1997), applicable to certain Boeing Model
727 series airplanes, to require repetitive inspections to detect
cracking of the rear spar web or fuel leakage of the wing center
section, and repair, if necessary. That action also provides for an
optional modification of the rear spar web that constitutes terminating
action for the repetitive inspections. That action was prompted by
several reports of fuel leakage due to cracking of the rear spar web of
the wing center section. The requirements of that AD are intended to
detect and correct such cracking of the rear spar web, which could
permit fuel leakage into the airflow multiplier, and could result in an
electrical short that could cause a fire.
Actions Since Issuance of Previous Rule
When AD 97-25-15 was issued, it contained a provision for the
optional modification of the rear spar web, which, if accomplished,
would constitute terminating action for the repetitive inspections
required by that AD. In the preamble to AD 97-25-15, the FAA indicated
that the actions required by that AD were considered ``interim action''
and that further rulemaking action was being considered to require the
modification of the rear spar web of the wing center section. The FAA
now has determined that further rulemaking action is indeed necessary,
and this proposed AD follows from that determination.
Explanation of Relevant Service Information
The FAA has reviewed and approved Boeing Service Bulletin 727-
57A0182, Revision 1, dated February 25, 1999. The procedures described
in Revision 1 are essentially similar to those described in the
original issue of the service bulletin, which was referenced as the
appropriate source of service information for the actions in AD 97-25-
15. Accomplishment of the modification specified 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 supersede AD 97-25-15, to continue to require
repetitive inspections to detect cracking of the rear spar web or fuel
leakage of the wing center section, and repair, if necessary. This
proposed AD would also require modification of the rear spar web, which
would constitute terminating action for the repetitive inspections.
These actions would be required to be accomplished in accordance with
the service bulletin described previously.
Cost Impact
There are approximately 970 airplanes of the affected design in the
worldwide fleet. The FAA estimates that 659 airplanes of U.S. registry
would be affected by this proposed AD: 641 ``Group 1'' airplanes and 18
``Group 2'' airplanes, as listed in the service bulletin.
The inspection that is currently required by AD 97-25-15 takes
approximately 2 work hours per
[[Page 54247]]
airplane to accomplish, at an average labor rate of $60 per work hour.
Based on these figures, the cost impact of the currently required
actions on U.S. operators is estimated to be $79,080, or $120 per
airplane, per inspection cycle.
The new modification that is proposed in this AD action would take
approximately 60 work hours per airplane to accomplish, at an average
labor rate of $60 per work hour. Required parts would cost
approximately $6,434 per airplane for ``Group 1'' airplanes, and $6,689
per airplane for ``Group 2'' airplanes. Based on these figures, the
cost impact of the proposed requirements of this AD on U.S. operators
is estimated to be $6,616,996, or $10,034 per ``Group 1'' airplane and
$10,289 per ``Group 2'' airplane.
The cost impact figures discussed above are based on assumptions
that no operator has yet accomplished any of the current or 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 removing amendment AD 97-25-15,
amendment 39-10239 (62 FR 65355, December 27, 1997), and by adding a
new airworthiness directive (AD), to read as follows:
Boeing: Docket 99-NM-75-AD. Supersedes AD 97-25-15, Amendment 39-
10239.
Applicability: Model 727 series airplanes having line numbers
858 through 864 inclusive, 867 through 869 inclusive, 872 through
883 inclusive, and 885 through 1832 inclusive; 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 (e)(1)
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 cracking of the rear spar web, which could permit
fuel leakage into the airflow multiplier, and could result in an
electrical short that could cause a fire, accomplish the following:
Restatement of the Requirements of AD 97-25-15
Inspections
(a) Prior to the accumulation of 15,000 total flight cycles, or
within 300 flight cycles after December 27, 1997 (the effective date
of AD 97-25-15, amendment 39-10239), whichever occurs later:
Accomplish the inspections specified in either paragraph (a)(1) or
(a)(2) of this AD, in accordance with Boeing Alert Service Bulletin
727-57A0182, dated September 18, 1997, or Boeing Service Bulletin
727-57A0182, Revision 1, dated February 25, 1999. For purposes of
the AD, the access panels specified in the alert service bulletin
need not be removed; the access panels need only be opened.
Note 2: The fuel tank of the wing center section may be filled
with fuel to assist in detecting cracking or fuel leakage during the
accomplishment of the visual inspections required by this AD.
(1) Perform a visual inspection using a borescope or mirror to
detect cracking of the rear spar web and/or fuel leakage of the wing
center section between right body buttock line (BBL) 40 and left BBL
40, in accordance with Part I of the Accomplishment Instructions of
the service bulletin. Thereafter, repeat this inspection at
intervals not to exceed 300 flight cycles. Or
(2) Perform an ultrasonic and high frequency eddy current (HFEC)
inspection to detect cracking of the rear spar web of the wing
center section between right BBL 40 and left BBL 40, in accordance
with Part II of the Accomplishment Instructions of the service
bulletin. Thereafter, repeat this inspection at intervals not to
exceed 3,000 flight cycles.
Repair
(b) If any cracking of the rear spar web and/or fuel leakage of
the wing center section is detected between right BBL 40 and left
BBL 40 near the upper machined land radius, prior to further flight,
repair in accordance with Part III of the Accomplishment
Instructions in Boeing Alert Service Bulletin 727-57A0182, dated
September 18, 1997, or Boeing Service Bulletin 727-57A0182, Revision
1, dated February 25, 1999. Accomplishment of this repair
constitutes terminating action for the repetitive inspection
requirements of this AD.
(c) If any cracking of the rear spar web and/or fuel leakage of
the wing center section is detected that is outside the area
specified in paragraph (b) of this AD, prior to further flight,
repair in accordance with a method approved by the Manager, Seattle
Aircraft Certification Office (ACO), FAA, Transport Airplane
Directorate. For a repair method to be approved by the Manager,
Seattle ACO, as required by this paragraph, the Manager's approval
letter must specifically reference this AD.
New Requirements of this AD
Modification
(d) Prior to the accumulation of 60,000 total flight cycles, or
within 3,000 flight cycles after the effective date of this AD,
whichever occurs later, accomplish an ultrasonic and HFEC inspection
in accordance with the requirements of paragraph (a)(2) of this AD.
(1) If no cracking is detected, prior to further flight, modify
the rear spar web of the center section of the fuel tank between
right BBL 40 and left BBL 40, in accordance with the Accomplishment
Instructions of Boeing Alert Service Bulletin 727-57A0182, dated
September 18, 1997, or Boeing Service Bulletin 727-57A0182, Revision
1, dated February 25, 1999. Accomplishment of this modification
constitutes terminating action for the repetitive inspection
requirements of this AD.
(2) If any cracking is detected, prior to further flight, repair
and modify in accordance with the Accomplishment Instructions of
Boeing Alert Service Bulletin 727-57A0182, dated September 18, 1997,
or Boeing Service Bulletin 727-57A0182, Revision 1, dated February
25, 1999. Accomplishment of this modification constitutes
terminating action for the
[[Page 54248]]
repetitive inspection requirements of this AD.
Alternative Methods of Compliance
(e)(1) 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.
(e)(2) Alternative methods of compliance, approved previously in
accordance with AD 97-25-15, amendment 39-10239, are approved as
alternative methods of compliance with this AD.
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 Permits
(f) Special flight permits may be issued in accordance with
Secs. 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, provided the
limitations specified in paragraphs (f)(1) through (f)(6) of this AD
are included in the special flight permit:
``(1) Required trip and reserve fuel must be carried in the No.
1 and No. 3 outer wing tanks.
(2) Wing center tank No. 2 must be empty of fuel.
(3) The fuel system must be checked for normal operation prior
to flight by verifying that all boost pumps are operational;
configuring the fuel system by turning on all boost pumps in the
No.'s 1 and 3 outer wing tanks and by opening all crossfeed valve
selectors; and by confirming that fuel is not bypassing tank No. 2
check valves by observing that there is not leakage into tank No. 2.
(4) Maintain a minimum of 5,300 pounds of fuel in tanks No. 1
and No. 3 to prevent uncovering the fuel bypass valve.
(5) The fuel quantity indication system must be operational in
all three tanks.
(6) The effects of loading fuel only in the wing tanks on the
airplane weight and balance must be considered and accounted for.''
Issued in Renton, Washington, on September 30, 1999.
D.L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 99-26089 Filed 10-5-99; 8:45 am]
BILLING CODE 4910-13-U