[Federal Register Volume 60, Number 73 (Monday, April 17, 1995)]
[Proposed Rules]
[Pages 19175-19179]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-9345]
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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39
[Docket No. 94-NM-185-AD]
Airworthiness Directives; British Aerospace Model BAC 1-11-200
and -400 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 British Aerospace Model
BAC 1-11-200 and -400 series airplanes. This proposal would require
various inspections to detect discrepancies of fuselage frames at
certain stations, and correction of discrepancies; and rework to limit
the maximum differential operating pressure of the fuselage. This
proposal would also require eventual modification of fuselage frames at
certain stations, which would terminate the repetitive inspection
requirements. This proposal is prompted by reports of fatigue cracking
in certain fuselage frames in the vicinity of the passenger door at
floor level due to fatigue-related stress. The actions specified by the
proposed AD are intended to prevent such fatigue-related cracking,
which could result in reduced structural integrity of the fuselage
pressure vessel and possible decompression of the pressurized cabin.
DATES: Comments must be received by May 26, 1995.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 94-NM-185-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 British Aerospace, Airbus Limited, P.O. Box 77, Bristol
BS99 7AR, England. This information may be examined at the FAA,
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton,
Washington.
[[Page 19176]] FOR FURTHER INFORMATION CONTACT: William Schroeder,
Aerospace Engineer, Standardization Branch, ANM-113, FAA, Transport
Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington 98055-
4056; telephone (206) 227-2148; fax (206) 227-1320.
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 94-NM-185-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. 94-NM-185-AD, 1601 Lind Avenue, SW., Renton, Washington
98055-4056.
Discussion
The Civil Aviation Authority (CAA), which is the airworthiness
authority for the United Kingdom, recently notified the FAA that an
unsafe condition may exist on certain British Aerospace Model BAC 1-11-
200 and -400 series airplanes. The CAA advises that reports have been
received of fatigue cracking in frames 178 and 213.5 in the vicinity of
the passenger door at floor level. Investigation revealed that such
cracking was caused by fatigue-related stress. Such fatigue-related
cracking, if not detected and corrected in a timely manner, could
result in reduced structural integrity of the fuselage pressure vessel
and possible decompression of the pressurized cabin.
British Aerospace has issued Alert Service Bulletin 53-A-PM5993,
Issue 1, dated January 11, 1993. This alert service bulletin describes
procedures for various repetitive inspections to detect structural
discrepancies of the various structural configurations of the fuselage
frames at stations 178 and 213.5, and correction of any discrepancy.
This alert service bulletin also describes procedures for rework to
limit the maximum differential operating pressure of the fuselage.
Additionally, this alert service bulletin describes procedures for
modification of fuselage frames at stations 178 and 213.5, which would
eliminate the need for the repetitive inspections. For airplanes
unrepaired or not reinforced by repair and operated at cabin
pressurization differentials not exceeding 7.5 pounds per square inch
(psi), the alert service bulletin describes procedures for the
installation of terminating Modification PM5993 at 55,000 total
landings. This modification introduces reinforcing structure to the
subject area. The CAA classified this alert service bulletin as
mandatory.
These airplane models are manufactured in the United Kingdom and
are type certificated for operation in the United States under the
provisions of Sec. 21.29 of the Federal Aviation Regulations (14 CFR
21.29) and the applicable bilateral airworthiness agreement. Pursuant
to this bilateral airworthiness agreement, the CAA has kept the FAA
informed of the situation described above. The FAA has examined the
findings of the CAA, reviewed all available information, and determined
that AD action is necessary for products of this type design that are
certificated for operation in the United States.
Since an unsafe condition has been identified that is likely to
exist or develop on other airplanes of the same type design registered
in the United States, the proposed AD would require various repetitive
inspections to detect structural discrepancies of the various
structural configurations of the fuselage frames at stations 178 and
213.5, and correction of any discrepancy. The proposed AD would also
require rework to limit the maximum differential operating pressure of
the fuselage. Additionally, this proposed AD would require eventual
modification of fuselage frames at stations 178 and 213.5, which would
constitute terminating action for the repetitive inspection
requirements. The actions would be required to be accomplished in
accordance with the alert service bulletin described previously.
The requirements of this proposed AD would differ from certain
actions recommended in the referenced alert service bulletin.
Specifically, for airplanes unrepaired or not reinforced by repair and
operated at cabin pressurization differentials not exceeding 7.5 psi,
the proposed AD would require installation of terminating Modification
PM5993 prior to the accumulation of 85,000 total landings, rather than
55,000 total landings as indicated in the alert service bulletin. The
higher threshold of 85,000 landings for modification has been
recommended by the Airworthiness Assurance Working Group (AAWG),
sponsored by the Air Transport Association (ATA) of America, the
Aerospace Industries Association (AIA), and the FAA. In selecting that
threshold, the AAWG considered the type of cracking involved, the
impact such cracking would have on the adjacent structure, and service
history of cracking in the subject area. The AAWG has recommended, and
the FAA concurs, that safety will not be compromised if Modification
PM5993 is installed prior to the accumulation of 85,000 total landings.
As a result of recent communications with the Air Transport
Association (ATA) of America, the FAA has learned that, in general,
some operators may misunderstand the legal effect of AD's on airplanes
that are identified in the applicability provision of the AD, but that
have been altered or repaired in the area addressed by the AD. The FAA
points out that all airplanes identified in the applicability provision
of an AD are legally subject to the AD. If an airplane has been altered
or repaired in the affected area in such a way as to affect compliance
with the AD, the owner or operator is required to obtain FAA approval
for an alternative method of compliance with the AD, in accordance with
the paragraph of each AD that provides for such approvals. A note has
been included in this notice to clarify this requirement.
The FAA estimates that 31 airplanes of U.S. registry would be
affected by this proposed AD.
It would take approximately 8 work hours per airplane to accomplish
the proposed inspection at an average labor rate of $60 per work hour.
Based on these figures, the total cost impact of the inspection
proposed by this AD on U.S. operators is estimated to be $14,880, or
$480 per airplane.
It would take approximately 80 work hours per airplane to
accomplish the [[Page 19177]] proposed modification at an average labor
rate of $60 per work hour. Required parts would cost approximately
$2,000 per airplane. Based on these figures, the total cost impact of
the modification proposed by this AD on U.S. operators is estimated to
be $210,800, or $6,800 per airplane.
Based on above figures, the total cost impact of the proposed
inspection and modification on U.S. operators is estimated to be
$225,680, or $7,280, per airplane.
The total 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.
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. App. 1354(a), 1421 and 1423; 49 U.S.C.
106(g); and 14 CFR 11.89.
Sec. 39.13 [Amended]
2. Section 39.13 is amended by adding the following new
airworthiness directive:
British Aerospace Airbus Limited (Formerly British Aerospace
Commercial Aircraft Limited, British Aerospace Aircraft Group):
Docket 94-NM-185-AD.
Applicability: Model BAC 1-11-200 and -400 series airplanes on
which British Aerospace Modifications PM5445 and PM5713 have not
been installed, 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 use the authority
provided in paragraph (h) to request approval from the FAA. This
approval may address either no action, if the current configuration
eliminates the unsafe condition; or different actions necessary to
address the unsafe condition described in this AD. Such a request
should include an assessment of the effect of the changed
configuration on the unsafe condition addressed by this AD. In no
case does the presence of any modification, alteration, or repair
remove any airplane from the applicability of this AD.
Compliance: Required as indicated, unless accomplished
previously.
To prevent fatigue-related cracking in fuselage frames at
stations 178 and 213.5 in the vicinity of the passenger door at
floor level, which could result in reduced structural integrity of
the fuselage pressure vessel and possible decompression of the
pressurized cabin, accomplish the following:
(a) For airplanes unrepaired or not reinforced by repair on
frames 178 and 213.5, in the area between stringers 25L and 27L:
Accomplish paragraphs (a)(1), (a)(2), (a)(3), and (a)(4) of this AD,
in accordance with British Aerospace Airbus Limited Alert Service
Bulletin 53-A-PM5993, Issue 1, dated January 11, 1993.
(1) Perform the initial inspection prior to the compliance time
specified in paragraph 2.1 of the Accomplishment Instructions of the
alert service bulletin or within 12 months after the effective date
of this AD, whichever occurs later. Repeat the inspection thereafter
at intervals specified in paragraph 2.1 of the Accomplishment
Instructions of the alert service bulletin.
(2) If any discrepancy is found during any inspection required
by paragraph (a)(1) of this AD, prior to further flight, correct the
discrepancy in accordance with paragraph 2.1 of the Accomplishment
Instructions of the alert service bulletin.
(3) Prior to the accumulation of the total number of landings
specified in paragraph 2.1.5 or 2.1.10, as applicable, of the
Accomplishment Instructions of the alert service bulletin or within
12 months after the effective date of this AD, whichever occurs
later, modify the structure of the fuselage frame at stations 178
and 213.5 in accordance with paragraph 2.1.5 or 2.1.10, as
applicable, of the Accomplishment Instructions of the alert service
bulletin. Accomplishment of this modification constitutes
terminating action for the requirements of paragraphs (a)(1) and
(a)(2) of this AD.
(4) Prior to the accumulation of 55,000 total landings or within
12 months after the effective date of this AD, whichever occurs
later, rework the cabin pressurization system to limit the maximum
differential operating pressure of the fuselage to 7.5 pounds per
square inch (psi), in accordance with the alert service bulletin.
(b) For airplanes on which Structural Repair Manual, figure 76,
repair in-situ has been acccomplished: Accomplish paragraphs (b)(1),
(b)(2), (b)(3), and (b)(4) of this AD, in accordance with British
Aerospace Airbus Limited Alert Service Bulletin 53-A-PM5993, Issue
1, dated January 11, 1993.
(1) Perform the initial inspection prior to the compliance time
specified in paragraph 2.2 of the Accomplishment Instructions of the
alert service bulletin or within 12 months after the effective date
of this AD, whichever occurs later. Repeat the inspection thereafter
at intervals specified in paragraph 2.2 of the Accomplishment
Instructions of the alert service bulletin.
(2) If any discrepancy is found during any inspection required
by paragraph (b)(1) of this AD, prior to further flight, correct the
discrepancy in accordance with paragraph 2.2 of the Accomplishment
Instructions of the alert service bulletin; or in accordance with a
method approved by the Manager, Standardization Branch, ANM-113,
FAA, Transport Airplane Directorate.
(3) Prior to the accumulation of the total number of landings
specified in paragraph 2.2.6 or 2.2.9, as applicable, of the
Accomplishment Instructions of the alert service bulletin or within
12 months after the effective date of this AD, whichever occurs
later, modify the structure of the fuselage frame at stations 178
and 213.5 in accordance with paragraph 2.2.6 or 2.2.9, as
applicable, of the Accomplishment Instructions of the alert service
bulletin. Accomplishment of this modification constitutes
terminating action for the requirements of paragraphs (b)(1) and
(b)(2) of this AD.
(4) Prior to the accumulation of 55,000 total landings or within
12 months after the effective date of this AD, whichever occurs
later, rework the cabin pressurization system to limit the maximum
differential operating pressure of the fuselage to 7.5 psi, in
accordance with the alert service bulletin.
(c) For airplanes on which Structural Repair Manual, figure 87,
repair has been accomplished: Accomplish paragraphs (c)(1), (c)(2),
(c)(3), and (c)(4) of this AD, in accordance with British Aerospace
Airbus Limited Alert Service Bulletin 53-A-PM5993, Issue 1, dated
January 11, 1993.
(1) Perform the initial inspection prior to the compliance time
specified in paragraph 2.3 of the Accomplishment Instructions of the
alert service bulletin or within 12 months after the effective date
of this AD, whichever occurs later. Repeat the inspection thereafter
[[Page 19178]] at intervals specified in paragraph 2.3 of the
Accomplishment Instructions of the alert service bulletin.
(2) If any discrepancy is found during any inspection required
by paragraph (c)(1) of this AD, prior to further flight, correct the
discrepancy in accordance with paragraph 2.3 of the Accomplishment
Instructions of the alert service bulletin; or in accordance with a
method approved by the Manager, Standardization Branch, ANM-113,
FAA, Transport Airplane Directorate.
(3) Prior to the accumulation of the total number of landings
specified in paragraph 2.3.5 or 2.3.8, as applicable, of the
Accomplishment Instructions of the alert service bulletin or within
12 months after the effective date of this AD, whichever occurs
later, modify the structure of the fuselage frames at stations 178
and 213.5 in accordance with paragraph 2.3.5 or 2.3.8, as
applicable, of the Accomplishment Instructions of the alert service
bulletin. Accomplishment of this modification constitutes
terminating action for the requirements of paragraphs (c)(1) and
(c)(2) of this AD.
(4) Prior to the accumulation of 55,000 total landings or within
12 months after the effective date of this AD, whichever occurs
later, rework the cabin pressurization system to limit the maximum
differential operating pressure of the fuselage to 7.5 psi, in
accordance with the alert service bulletin.
(d) For airplanes on which Structural Repair Manual, figure 110
or 111, repair has been accomplished: Accomplish paragraphs (d)(1),
(d)(2), (d)(3), and (d)(4) of this AD, in accordance with British
Aerospace Airbus Limited Alert Service Bulletin 53-A-PM5993, Issue
1, dated January 11, 1993.
(1) Perform the initial inspection prior to the compliance time
specified in paragraph 2.4 of the Accomplishment Instructions of the
alert service bulletin or within 12 months after the effective date
of this AD, whichever occurs later. Repeat the inspection thereafter
at intervals specified in paragraph 2.4 of the Accomplishment
Instructions of the alert service bulletin.
(2) If any discrepancy is found during any inspection required
by paragraph (d)(1) of this AD, prior to further flight, correct the
discrepancy in accordance with a method approved by the Manager,
Standardization Branch, ANM-113, FAA, Transport Airplane
Directorate.
(3) Prior to the accumulation of the total number of landings
specified in paragraph 2.4.5 or 2.4.8, as applicable, of the
Accomplishment Instructions of the alert service bulletin or within
12 months after the effective date of this AD, whichever occurs
later, modify the structure of the fuselage frames at stations 178
and 213.5 in accordance with paragraph 2.4.5 or 2.4.8, as
applicable, of the Accomplishment Instructions of the alert service
bulletin. Accomplishment of this modification constitutes
terminating action for the requirements of paragraphs (d)(1) and
(d)(2) of this AD.
(4) Prior to the accumulation of 55,000 total landings or within
12 months after the effective date of this AD, whichever occurs
later, rework the cabin pressurization system to limit the maximum
differential operating pressure of the fuselage to 7.5 psi, in
accordance with the alert service bulletin.
(e) For airplanes on which Structural Repair Manual, figure 76,
reinforcement has been accomplished: Accomplish paragraphs (e)(1),
(e)(2), (e)(3), (e)(4), and (e)(5) of this AD, in accordance with
British Aerospace Airbus Limited Alert Service Bulletin 53-A-PM5993,
Issue 1, dated January 11, 1993.
(1) Perform the initial inspection prior to the compliance time
specified in paragraph 2.5 of the Accomplishment Instructions of the
alert service bulletin or within 12 months after the effective date
of this AD, whichever occurs later. Repeat the inspection thereafter
at intervals specified in paragraph 2.5 of the Accomplishment
Instructions of the alert service bulletin.
(2) If any discrepancy is found during any inspection required
by paragraph (e)(1) of this AD, prior to further flight, correct the
discrepancy in accordance with paragraph 2.5 of the Accomplishment
Instructions of the alert service bulletin; or in accordance with a
method approved by the Manager, Standardization Branch, ANM-113,
FAA, Transport Airplane Directorate.
(3) Prior to the accumulation of the total number of landings
specified in paragraph 2.5.5 or 2.5.10, as applicable, of the
Accomplishment Instructions of the alert service bulletin or within
12 months after the effective date of this AD, whichever occurs
later, modify the structure of the fuselage frames at stations 178
and 213.5 in accordance with paragraph 2.5.5 or 2.5.10, as
applicable, of the Accomplishment Instructions of the alert service
bulletin. Accomplishment of this modification constitutes
terminating action for the requirements of paragraphs (e)(1) and
(e)(2) of this AD.
(4) For airplanes operated at a cabin maximum pressure
differential in excess of 7.5 psi, prior to the threshold times
specified in Table C of the service bulletin, replace the
reinforcements accomplished in accordance with the Structural Repair
Manual, figure 76, with reinforcements accomplished in accordance
with Structural Repair Manual 53-02-00, figure 110 or 111, as
specified in the alert service bulletin.
(5) Prior to the accumulation of 55,000 total landings or within
12 months after the effective date of this AD, whichever occurs
later, rework the cabin pressurization system to limit the maximum
differential operating pressure of the fuselage to 7.5 psi, in
accordance with the alert service bulletin.
(f) For airplanes on which Structural Repair Manual, figure 87,
reinforcement has been accomplished: Accomplish paragraphs (f)(1),
(f)(2), (f)(3), and (f)(4) of this AD, in accordance with British
Aerospace Airbus Limited Alert Service Bulletin 53-A-PM5993, Issue
1, dated January 11, 1993.
(1) Perform the initial inspection prior to the compliance time
specified in paragraph 2.6 of the Accomplishment Instructions of the
alert service bulletin or within 12 months after the effective date
of this AD, whichever occurs later. Repeat the inspection thereafter
at intervals specified in paragraph 2.6 of the Accomplishment
Instructions of the alert service bulletin.
(2) If any discrepancy is found during any inspection required
by paragraph (f)(1) of this AD, prior to further flight, correct the
discrepancy in accordance with paragraph 2.6 of the Accomplishment
Instructions of the alert service bulletin; or in accordance with a
method approved by the Manager, Standardization Branch, ANM-113,
FAA, Transport Airplane Directorate.
(3) Prior to the accumulation of the total number of landings
specified in paragraph 2.6.6 or 2.6.9, as applicable, of the
Accomplishment Instructions of the alert service bulletin or within
12 months after the effective date of this AD, whichever occurs
later, modify the structure of the fuselage frames at stations 178
and 213.5 in accordance with paragraph 2.6.6 or 2.6.9, as
applicable, of the Accomplishment Instructions of the alert service
bulletin. Accomplishment of this modification constitutes
terminating action for the requirements of paragraphs (f)(1) and
(f)(2) of this AD.
(4) Prior to the accumulation of 55,000 total landings or within
12 months after the effective date of this AD, whichever occurs
later, rework the cabin pressurization system to limit the maximum
differential operating pressure of the fuselage to 7.5 psi, in
accordance with the alert service bulletin.
(g) For airplanes on which repairs other than those described in
the Structural Repair Manual have been accomplished on frames 178
and 213.5, in the area between stringers 25L and 27L: Accomplish
paragraphs (g)(1), (g)(2), and (g)(3) of this AD.
(1) Within 6 months after the effective date of this AD, submit
the following for approval to the Manager, Standardization Branch,
ANM-113, FAA, Transport Airplane Directorate:
(i) Procedures and schedule for accomplishing the initial and
repetitive inspections of the fuselage frames at stations 178 and
213.5; and
(ii) Schedule for installation of Modification PM5993 or
Structural Repair Manual, figure 110 and 111, as applicable, at the
fuselage frames at stations 178 and 213.5.
(2) Within 6 months after the procedures and schedules are
approved, revise the FAA-approved maintenance program to include
these procedures.
(3) Prior to the accumulation of 55,000 total landings or within
12 months after the effective date of this AD, whichever occurs
later, rework the cabin pressurization system to limit the maximum
differential operating pressure of the fuselage to 7.5 psi, in
accordance with British Aerospace Airbus Limited Alert Service
Bulletin 53-A-PM5993, Issue 1, dated January 11, 1993.
(h) 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, Standardization Branch, ANM-113,
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,
Standardization Branch, ANM-113.
Note 2: Information concerning the existence of approved
alternative methods of [[Page 19179]] compliance with this AD, if
any, may be obtained from the Standardization Branch, ANM-113.
(i) 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.
Issued in Renton, Washington, on April 11, 1995.
S.R. Miller,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 95-9345 Filed 4-14-95; 8:45 am]
BILLING CODE 4910-13-U
