[Federal Register Volume 59, Number 249 (Thursday, December 29, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-32034]
[[Page Unknown]]
[Federal Register: December 29, 1994]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
14 CFR Part 39
[Docket No. 94-NM-188-AD]
Airworthiness Directives; Boeing Model 757 Series Airplanes
Equipped With Rolls Royce Engines
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 757
series airplanes, that currently requires inspections to detect
fatigue-related cracking or breakage of the hydraulic tubing support
brackets located on the upper spar web in the engine struts; further
inspection to detect related damage of the upper spar web, the fuel
lines, and the hydraulic lines, as necessary; and repair or replacement
of cracked or damaged parts. That AD was prompted by reports of
fatigue-related cracks in the hydraulic tubing support brackets located
on the upper spar web in the engine struts. The actions specified by
that AD are intended to prevent such fatigue-related cracking, which
could result in fuel or hydraulic fluid leakage into the interior of
the engine strut and cause a fire. This proposal would require
installation of a previously optional terminating action.
DATES: Comments must be received by February 27, 1995.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 94-NM-188-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: Sheila Kirkwood, Aerospace Engineer,
Systems and Equipment Branch, ANM-130S, FAA, Transport Airplane
Directorate, Seattle Aircraft Certification Office, 1601 Lind Avenue,
SW., Renton, Washington 98055-4056; telephone (206) 227-2675; fax (206)
227-1182.
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-188-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-188-AD, 1601 Lind Avenue, SW., Renton, Washington
98055-4056. Discussion -
On February 4, 1994, the FAA issued AD 94-04-04, amendment 39-8822
(59 FR 6542, February 11, 1994). [A correction of the rule was
published in the Federal Register on March 10, 1994 (59 FR 11182).]
That AD is applicable to certain Boeing Model 757 series airplanes
equipped with Rolls Royce engines. It requires repetitive inspections
to detect fatigue-related cracking or breakage of the hydraulic tubing
support brackets manufactured from 2219 aluminum, 2024-T42 aluminum
alloy, or 301 stainless steel. These brackets are located on the upper
spar web in the engine struts. That AD requires further inspection to
detect related damage of the upper spar web, the fuel lines, and the
hydraulic lines, as necessary; and repair or replacement of cracked or
damaged parts. That action was prompted by reports of fatigue-related
cracks in the hydraulic tubing support brackets located on the upper
spar web in the engine struts. The requirements of that AD are intended
to prevent such fatigue cracking, which could result in fuel and
hydraulic fluid leakage into the interior of the engine strut and cause
a fire. -
That AD also provides for an optional terminating action which, if
accomplished, would constitute terminating action for the required
repetitive inspections. That optional terminating action entails
replacement of support brackets made of 2219 aluminum, 2024-T42
aluminum alloy, or 301 stainless steel, with support brackets made of
nickel alloy. Nickel alloy support brackets are less susceptible to the
type of cracking problems identified in brackets made of other
materials. -
In the preamble to AD 94-04-04, the FAA indicated that the required
repetitive inspections were considered ``interim action,'' and that
further rulemaking action was being considered to mandate the optional
terminating action. The FAA has determined that installation of nickel
alloy brackets will positively address the unsafe condition identified
as fatigue-related cracking in the hydraulic tubing support brackets,
which can result in fuel or hydraulic fluid leakage into the interior
of the engine strut and cause a fire. Based on this determination, the
FAA finds that further rulemaking action is indeed necessary, and this
proposed rule follows from that determination. -
The FAA has reviewed and approved Boeing Alert Service Bulletin
757-54A0030, Revision 1, dated December 20, 1993, which describes
procedures for: -
1. a one-time inspection using a magnet to determine whether the
forward support bracket for the hydraulic tubing in the upper spar web
of each engine strut is manufactured from 17-7PH steel; -
2. an initial visual inspection to detect fatigue-related cracking
or breakage of all support brackets that are not manufactured from 17-
7PH steel; -
3. a visual inspection to detect related damage of the upper spar
web, the fuel lines, and the hydraulic lines, as necessary, if any
completely broken or cracked support bracket is found as a result of
the initial inspection; -
4. removal, and either repair or replacement of damaged parts with
new or serviceable parts; and -
5. replacement of all existing support brackets manufactured from
2219 aluminum, 2024-T42 aluminum alloy, or 301 stainless steel with new
nickel alloy support brackets. (Accomplishment of this replacement
eliminates the need for the repetitive inspections.) -
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 94-04-04. It would continue to require
inspections to detect fatigue-related cracking or breakage of the
hydraulic tubing support brackets located on the upper spar web in the
engine struts; further inspection to detect related damage of the upper
spar web, the fuel lines, and the hydraulic lines, as necessary; and
removal, and either repair or replacement of cracked or damaged parts.
The proposed AD also would require replacement of all existing support
brackets manufactured from 2219 aluminum, 2024-T42 aluminum alloy, or
301 stainless steel with new nickel alloy support brackets; this
replacement would constitute terminating action for the repetitive
inspection requirements. The actions would be required to be
accomplished in accordance with the service bulletin described
previously. -
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.-
There are approximately 132 Boeing Model 757 series airplanes
equipped with Rolls Royce engines of the affected design in the
worldwide fleet. The FAA estimates that 102 airplanes of U.S. registry
would be affected by this proposed AD. -
The actions currently required by AD 94-04-04 take approximately 4
work hours per airplane to accomplish, at an average labor rate of $60
per work hour. Based on these figures, the total cost impact of the
currently required actions on U.S. operators is estimated to be
$24,480, or $240 per airplane. -
The proposed replacement actions would take approximately 40 work
hours per airplane to accomplish the proposed actions, at an average
labor rate of $60 per work hour. Required parts would cost
approximately $1,044 per airplane. Based on these figures, the total
cost impact of the proposed replacement actions on U.S. operators is
estimated to be $351,288, or $3,444 per airplane. -
The total cost impact figures discussed above are 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 removing amendment 39-8822 (59 FR
11182, March 10, 1994), and by adding a new airworthiness directive
(AD), to read as follows:
Boeing: Docket 94-NM-188-AD. Supersedes AD 94-04-04, amendment 39-
8822.
-Applicability: Model 757 series airplanes equipped with Rolls
Royce engines; as listed in Boeing Alert Service Bulletin 757-54A0030,
Revision 1, dated December 20, 1993; 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 fuel or hydraulic fluid leakage into the interior of
the engine strut, which could cause a fire, accomplish the
following: -
(a) For Group 2 Airplanes: Within 60 days after February 28,
1994 (the effective date of AD 94-04-04, amendment 39-8822), perform
an inspection using a magnet to determine whether the forward
support bracket for the hydraulic tubing on the upper spar web of
each engine strut is manufactured from 17-7PH steel, in accordance
with Boeing Alert Service Bulletin 757-54A0030, Revision 1, dated
December 20, 1993. If any forward support bracket is manufactured
from 17-7PH steel, no further action is required by this AD for that
forward bracket.
-Note 2: The brackets positioned after the forward bracket
should be manufactured from 17-7PH steel, as shown below:
------------------------------------------------------------------------
(Power plant
Bracket Part No. station No.)
------------------------------------------------------------------------
First Bracket-.............. 312N5817-13 (or equivalent)- PPS 102
Second Bracket-............. 312N5817-19 (or equivalent)- PPS 120
Third Bracket-.............. 312N5817-23 (or equivalent)- PPS 129
Fourth Bracket-............. 312N5817-25 (or equivalent)- PPS 145
------------------------------------------------------------------------
(b) For Groups 1 and 2 Airplanes: Within 60 days after February
28, 1994 (the effective date of AD 94-04-04, amendment 39-8822)(for
Group 1 airplanes), and prior to further flight following the
inspection required by paragraph (a) of this AD (for Group 2
airplanes), perform an initial visual inspection to detect fatigue-
related cracks or breakage on the hydraulic tubing support brackets
not manufactured of 17-7PH steel on the upper spar web of each
engine strut, in accordance with Boeing Alert Service Bulletin 757-
54A0030 , Revision 1, dated December 20, 1993. If any discrepancy is
detected, prior to further flight, accomplish the following in
accordance with the alert service bulletin: -
(1) For any support bracket that is completely broken: Perform a
further visual inspection to detect worn areas or other damage of
the upper spar web, the fuel lines, and the hydraulic lines; and
prior to further flight, accomplish paragraphs (b)(1)(i),
(b)(1)(ii), (b)(1)(iii), and (b)(1)(iv) of this AD in accordance
with the alert service bulletin: -
(i) Repair any damaged upper spar web. -
(ii) Repair or replace any damaged fuel line with new or
serviceable parts, as necessary. -
(iii) Replace any damaged hydraulic line with new or serviceable
parts. -
(iv) Remove any broken support bracket; and, except as provided
by paragraph (c) of this AD, replace it with a new nickel alloy
bracket. -
(2) For any support bracket that is cracked, but not completely
broken: Perform a further visual inspection to detect damage of the
hydraulic pressure line only; and prior to further flight,
accomplish paragraphs (b)(2)(i) and (b)(2)(ii) of this AD in
accordance with the alert service bulletin: -
(i) Replace any damaged hydraulic pressure line with new or
serviceable parts, as necessary. -
(ii) Remove any cracked support bracket; and, except as provided
by paragraph (c) of this AD, replace it with a new nickel alloy
bracket. -
(c) For any airplane having a support bracket that is removed
during accomplishment of paragraph (b)(1)(iv) or (b)(2)(ii) of this
AD: The following number of flights are permitted prior to
replacement of any removed support bracket with a new nickel alloy
bracket (in accordance with Boeing Alert Service Bulletin 757-
54A0030, Revision 1, dated December 20, 1993), provided that, prior
to further flight, the cracked or broken brackets are removed
completely, damaged spar webs are repaired, and fuel lines and
hydraulic lines are repaired or replaced, in accordance with
paragraph (b) of this AD:
------------------------------------------------------------------------
Part No. (Power Plant
Bracket Station Number) Flights Permitted
------------------------------------------------------------------------
-First Bracket Removed- P/N 312N5817-55 (PPS 102)- No Flights.-
.
Second Bracket Removed- P/N 312N5817-69 (PPS 120)- Ten Flights.-
.
Third Bracket Removed- P/N 312N5817-73 (PPS 129)- Ten Flights.-
Fourth Bracket Removed P/N 312N5817-75 (PPS 145)- Three Flights. -
-.
Second and Third .......................... One Flight. -
Brackets Removed.
Multiple Brackets, -......................... No Flights.
other than Second and
Third.
------------------------------------------------------------------------
-(d) For any airplane having a support bracket that is
manufactured from 2024-T42 aluminum alloy or 301 stainless steel:
Repeat the initial inspection required by paragraph (b) of this AD
thereafter at intervals not to exceed 2,000 flight hours in
accordance with the procedures described in Boeing Alert Service
Bulletin 757-54A0030, Revision 1, dated December 20, 1993. -
(e) For any airplane having a support bracket that is
manufactured from 2219 aluminum: Repeat the initial inspection
required by paragraph (b) of this AD thereafter at intervals not to
exceed 1,000 flight hours in accordance with the procedures
described in Boeing Alert Service Bulletin 757-54A0030, Revision 1,
dated December 20, 1993. -
(f) Within 18 months after the effective date of this AD:
Replace all support brackets manufactured from 2219 aluminum, 2024-
T42 aluminum alloy, or 301 stainless steel with new nickel alloy
hydraulic tubing support brackets for the hydraulic tubing on the
upper spar web of the engine struts at all locations, in accordance
with the requirements of Boeing Alert Service Bulletin 757-54A0030,
Revision 1, dated December 20, 1993. Accomplishment of this
modification constitutes terminating action for the requirements of
this AD. -
(g) As of February 28, 1994 (the effective date of AD 94-04-04,
amendment 39-8822), no person shall install any hydraulic tubing
support bracket on the upper spar web of the engine struts that is
manufactured from 2219 aluminum, 2024-T42 aluminum alloy, or 301
stainless steel on any airplane. -
(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, 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 3: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Seattle ACO.
-(i) 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 December 22, 1994.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 94-32034 Filed 12-28-94; 8:45 am]
BILLING CODE 4910-13-P
