[Federal Register Volume 61, Number 48 (Monday, March 11, 1996)]
[Rules and Regulations]
[Pages 9601-9604]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-5367]
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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39
[Docket No. 94-NM-71-AD; Amendment 39-9534; AD 96-05-08]
Airworthiness Directives; Boeing Model 757 Series Airplanes
Equipped With Rolls Royce Engines
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule.
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SUMMARY: This amendment supersedes an existing airworthiness directive
(AD), applicable to certain Boeing Model 757 series airplanes, that
currently requires repetitive inspections to detect cracking in the
midspar fuse pins and replacement of certain fuse pins. This amendment
adds requirements to inspect straight fuse pins and replace any cracked
straight fuse pins with either new corrosion-resistant steel fuse pins
or like pins; replace bulkhead fuse pins with new corrosion-resistant
steel fuse pins; and repetitively inspect newly installed fuse pins.
This amendment is prompted by the development of new corrosion-
resistant steel fuse pins. The actions specified by this AD are
intended to prevent cracking of the midspar fuse pins, which may lead
to separation of the strut and engine from the wing of the airplane.
DATES: Effective April 10, 1996.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of April 10, 1996.
ADDRESSES: The service information referenced in this AD may be
obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle,
[[Page 9602]]
Washington 98124-2207. This information may be examined at the Federal
Aviation Administration (FAA), Transport Airplane Directorate, Rules
Docket, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of
the Federal Register, 800 North Capitol Street, NW., suite 700,
Washington, DC.
FOR FURTHER INFORMATION CONTACT: Carrie Sumner, Aerospace Engineer,
Airframe Branch, ANM-120S, FAA, Transport Airplane Directorate, Seattle
Aircraft Certification Office, 1601 Lind Avenue, SW., Renton,
Washington 98055-4056; telephone (206) 227-2778; fax (206) 227-1181.
SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal
Aviation Regulations (14 CFR part 39) by superseding AD 93-16-08,
amendment 39-8665 (58 FR 45041, August 26, 1993), which is applicable
to certain Boeing Model 757 series airplanes, was published as a
supplemental notice of proposed rulemaking in the Federal Register on
May 18, 1995 (60 FR 26697). That action proposed to add a requirement
to inspect straight fuse pins and replace any cracked straight fuse
pins with either new corrosion-resistant steel fuse pins or like pins;
replace bulkhead fuse pins with new corrosion-resistant steel fuse
pins; and repetitively inspect newly installed fuse pins.
Interested persons have been afforded an opportunity to participate
in the making of this amendment. Due consideration has been given to
the comments received.
One commenter, an affected operator, requests that the
applicability of the proposed rule be revised to exclude any new
airplanes that are delivered with the new, improved fuse pins already
installed. This commenter presents two reasons for this request:
1. The commenter recently received airplanes that were already
equipped with the new (15-5PH) mid spar fuse pins. These particular
airplanes are not included in the effectivity listing of the Boeing
service bulletin that was referenced in the proposed rule. Since
applicability of the proposed rule would include all Model 757's
equipped with Rolls Royce engines, the commenter's airplanes would be
subject to the requirements of the AD, even though these airplanes were
not listed in the referenced service bulletin.
2. New airplanes delivered with the new fuse pins will be
inspected, and any replacement of fuse pins can be made, under the
regular maintenance program.
The FAA does not concur with the commenter's request.
As for Item 1, the applicability of an AD takes precedence over the
effectivity listing of a service bulletin. Further, the inspection and
replacement procedures outlined in the referenced Boeing service
bulletin can be accomplished on any Model 757, and are not specifically
tailored only to airplanes specified in the effectivity listing of the
service bulletin.
As for Item 2, the FAA is not aware of any current maintenance
program requirement that includes the inspection and replacement of 15-
5PH fuse pins at the intervals set forth in this AD. The FAA
established the intervals based on the manufacturer's analysis and
testing, which demonstrated that the 15-5PH fuse pin has a fatigue
threshold of 14,000 flight cycles. This identified threshold is
applicable to all 15-5PH fuse pins, regardless of whether or not the
airplane on which they are installed is listed in the referenced Boeing
service bulletin. If the fuse pins are not replaced or inspected at the
times required by this AD, the safety concerns associated with fracture
of the fuse pins will still exist. The FAA considers issuance of this
AD to be necessary, since AD's are the means by which the
accomplishment of procedures and adherence to specific necessary
compliance times are made mandatory.
This same commenter contends that the manufacturer should revise
the referenced Boeing service bulletin to include procedures for eddy
current inspections of the 15-5PH fuse pins, as well as instructions
for removal and replacement of those pins. The revised service bulletin
should also include a listing of all applicable airplanes. The
commenter requests that the proposed rule be changed to reference the
revised service bulletin.
The FAA does not concur that a change to the rule is necessary. As
for the procedures for inspections, the referenced Boeing service
bulletin specifies that they can be found in the 757 Nondestructive
Test (NDT) Manual, Part 6, Subject 54-40-01, Figure 1 (this is noted on
page 16 of the Boeing service bulletin). As for removal and replacement
procedures, Figure 4 of the referenced Boeing service bulletin displays
a detail of the 15-5PH fuse pin installation that can be used in
accomplishing those actions. As for the listing of applicable
airplanes, while it may be convenient for operators to have all
affected airplanes listed in the service bulletin, the FAA reiterates
that the applicability statement of an AD takes precedence over the
effectivity listing of any service bulletin. The FAA does intend to
recommend to Boeing that, whenever it plans to revise Service Bulletin
757-54A0020, the procedures for inspection, removal, and replacement of
the 15-5PH fuse pins be included.
One commenter requests that paragraph (a)(2)(ii) of the proposal be
revised to indicate that installation of the new 15-5PH fuse pins
constitutes terminating action for the inspections of the older style
fuse pins. This commenter asserts that the new pins have not yet been
shown to be unsafe in-service. Further, once the new 15-5PH pins are
installed, they can be regularly inspected under the operator's FAA-
approved maintenance program.
The FAA does not concur. As indicated earlier, the manufacturer has
demonstrated, by analysis supported by tests, that the 15-5PH fuse pin
has a fatigue threshold of 14,000 flight cycles. In fact, in Revision 5
of Boeing Service Bulletin 757-54A0020, which was referenced in the
proposed AD, the manufacturer recommends that all 15-5PH fuse pins be
replaced with new pins after 14,000 flight cycles. As an option, at
14,000 flight cycles, the 15-5PH fuse pins may be examined for cracks
and, if no cracking is evident, they may be continually reexamined at
3,500 flight cycle intervals. The FAA has determined that this
inspection schedule is both appropriate and warranted to address the
unsafe condition that arises from the consequences of fractured fuse
pins. Also, as indicated earlier, the FAA is not aware of any current
maintenance program requirement that includes the inspection and
replacement of 15-5PH fuse pins at the intervals set forth in this AD.
The FAA finds that the issuance of this AD is necessary in order to
ensure that the accomplishment of the procedures and the adherence to
specific compliance times are achieved.
After careful review of the available data, including the comments
noted above, the FAA has determined that air safety and the public
interest require the adoption of the rule as proposed.
There are approximately 306 Model 757 series airplanes equipped
with Rolls Royce engines of the affected design in the worldwide fleet.
The FAA estimates that 119 airplanes of U.S. registry will be affected
by this proposed AD.
The inspections that were previously required by AD 93-16-08, and
retained in this new AD, take approximately 8 work hours per fuse pin;
there are 4 fuse pins per airplane. The average labor rate is
approximately $60 per work hour. Based on these figures, the current
cost impact of these inspections on U.S. operators is estimated to be
$228,480, or $1,920 per airplane, per inspection
[[Page 9603]]
cycle. However, since the integrity and strength of the new steel fuse
pins permit longer inspection intervals, the cost impact of these
inspections will be lessened, since the inspections are not required to
be performed as frequently as they were previously required under AD
93-16-08.
The replacement that is required by this new AD will take
approximately 56 work hours per fuse pin, at an average labor rate of
$60 per work hour. Required parts will be provided by the manufacturer
at no cost to the operator. Based on these figures, the cost impact of
the replacement action on U.S. operators is estimated to be $1,599,360,
or $13,440 per airplane.
The 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 adopted herein will 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 final
rule does not have sufficient federalism implications to warrant the
preparation of a Federalism Assessment.
For the reasons discussed above, I certify that this action (1) is
not a ``significant regulatory action'' under Executive Order 12866;
(2) is not a ``significant rule'' under DOT Regulatory Policies and
Procedures (44 FR 11034, February 26, 1979); and (3) 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 final evaluation has been prepared for this action
and it is contained in the Rules Docket. A copy of it may be obtained
from the Rules Docket at the location provided under the caption
ADDRESSES.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
Adoption of the Amendment
Accordingly, pursuant to the authority delegated to me by the
Administrator, the Federal Aviation Administration amends 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 USC 106(g), 40113, 44701.
Sec. 39.13 [Amended]
2. Section 39.13 is amended by removing amendment 39-8665 (58 FR
45041, August 26, 1993), and by adding a new airworthiness directive
(AD), amendment 39-9534, to read as follows:
96-05-08 Boeing: Amendment 39-9534. Docket 94-NM-71-AD. Supersedes
AD 93-16-08, Amendment 39-8665.
Applicability: Model 757 series airplanes equipped with Rolls
Royce engines, 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 (f) 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.
Note 2: Inspections accomplished prior to the effective date of
this amendment in accordance with the procedures described in Boeing
Service Bulletin 757-54A0020, Revision 4, dated May 27, 1993;
Revision 3, dated March 26, 1992; or Revision 2, dated October 31,
1991; are considered acceptable for compliance with the applicable
inspection specified in this amendment.
To prevent cracking of the midspar fuse pins, which may lead to
separation of the strut and engine from the wing of the airplane,
accomplish the following:
(a) For airplanes equipped with straight fuse pins, part number
(P/N) 311N5067-1: Prior to the accumulation of 5,000 total flight
cycles on the straight fuse pin, perform an eddy current inspection
to detect cracking in those fuse pins, in accordance with Boeing
Service Bulletin 757-54A0020, Revision 5, dated March 17, 1994.
(1) If no cracking is detected, repeat the inspection thereafter
at intervals not to exceed 1,500 flight cycles on the straight fuse
pin.
(2) If any cracking is detected, prior to further flight,
accomplish the requirements of either paragraph (a)(2)(i) or
(a)(2)(ii) of this AD.
(i) Replace the cracked straight fuse pin with a new straight
fuse pin, P/N 311N5067-1, and prior to the accumulation of 5,000
total flight cycles on the newly installed straight fuse pin,
perform an eddy current inspection, in accordance with the service
bulletin. Repeat the inspection thereafter at intervals not to
exceed 1,500 flight cycles on the newly installed straight fuse pin.
Or
(ii) Replace the cracked straight fuse pin with a new 15-5PH
fuse pin, P/N 311N5217-1, and prior to the accumulation of 14,000
total flight cycles on the newly installed 15-5PH fuse pin, perform
an eddy current inspection to detect cracking in the newly installed
pin, in accordance with the procedures described in the service
bulletin. Repeat the inspection thereafter at intervals not to
exceed 3,500 flight cycles on the newly installed fuse pin.
(b) For airplanes equipped with refinished straight fuse pins,
P/N 311N5067-1: Perform an eddy current inspection to detect
cracking in those fuse pins at intervals not to exceed 1,500 flight
cycles on the refinished fuse pins, in accordance with Boeing
Service Bulletin 757-54A0020, Revision 5, dated March 17, 1994.
(1) If no cracking is detected, repeat the inspection thereafter
at intervals not to exceed 1,500 flight cycles on the refinished
straight fuse pin.
(2) If any cracking is detected, prior to further flight,
accomplish the requirements of either paragraph (b)(2)(i),
(b)(2)(ii), or (b)(2)(iii) of this AD, in accordance with the
service bulletin.
(i) Replace the cracked refinished straight fuse pin with a
crack-free refinished straight fuse pin, P/N 311N5067-1, and perform
an eddy current inspection to detect cracking in the refinished
straight fuse pin at intervals not to exceed 1,500 flight cycles, in
accordance with the procedures described in the service bulletin. Or
(ii) Replace the cracked refinished straight fuse pin with a new
straight fuse pin, P/N 311N5067-1, and prior to the accumulation of
5,000 total flight cycles on the newly installed straight fuse pin,
perform an eddy current inspection, in accordance with the service
bulletin. Repeat the inspection thereafter at intervals not to
exceed 1,500 flight cycles on the newly installed straight fuse pin.
Or
(iii) Replace the cracked refinished straight fuse pin with a
new 15-5PH fuse pin, P/N 311N5217-1, and prior to the accumulation
of 14,000 total flight cycles on the newly installed 15-5PH fuse
pin, perform an eddy current inspection to detect cracking in the
newly installed pin, in accordance with the procedures described in
the service bulletin. Repeat the inspection thereafter at intervals
not to exceed 3,500 flight cycles on the newly installed fuse pin.
(c) For airplanes equipped with bulkhead fuse pins, P/N
311N5211-1: Within 3,000 flight cycles after the effective date of
this AD, replace the bulkhead fuse pins with 15-5PH fuse pins, P/N
311N5217-1, in accordance with Boeing Service Bulletin 757-54A0020,
Revision 5, dated March 17, 1994, and accomplish the requirements of
paragraph (d) of this AD.
(d) For airplanes equipped with 15-5PH fuse pins: Prior to the
accumulation of 14,000 total flight cycles on the 15-5PH fuse pins,
perform an eddy current inspection to detect cracking in those fuse
pins, in accordance with the procedures described in Boeing Service
Bulletin 757-54A0020, Revision 5, dated March 17, 1994.
[[Page 9604]]
(1) If no cracking is detected, repeat the inspection thereafter
at intervals not to exceed 3,500 flight cycles on the fuse pin.
(2) If any cracking is detected, accomplish the requirements of
paragraphs (d)(2)(i) and (d)(2)(ii) of this AD.
(i) Prior to further flight, replace any cracked 15-5PH fuse pin
with a new 15-5PH fuse pin, P/N 311N5217-1, in accordance with the
procedures described in the service bulletin. And
(ii) Prior to the accumulation of 14,000 total flight cycles on
the newly installed 15-5PH fuse pin, perform an eddy current
inspection to detect cracking in the newly installed pin, in
accordance with the procedures described in the service bulletin.
Repeat the inspection thereafter at intervals not to exceed 3,500
flight cycles on the newly installed fuse pin.
(e) Fuse pins must be of the same type on the same strut. For
example, a steel fuse pin having P/N 311N5067-1 may not be installed
on the same strut that has a corrosion-resistant steel (CRES) fuse
pin having P/N 311N5217-1 installed on that strut. However, fuse
pins on one strut may differ from those on another strut, provided
the fuse pins are not of mixed types on the same strut.
(f) 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.
(g) 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.
(h) The actions shall be done in accordance with Boeing Service
Bulletin 757-54A0020, Revision 5, dated March 17, 1994. This
incorporation by reference was approved by the Director of the
Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part
51. Copies may be obtained from Boeing Commercial Airplane Group,
P.O. Box 3707, Seattle, Washington 98124-2207. Copies may be
inspected at the FAA, Transport Airplane Directorate, 1601 Lind
Avenue, SW., Renton, Washington; or at the Office of the Federal
Register, 800 North Capitol Street, NW., suite 700, Washington, DC.
(i) This amendment becomes effective on April 10, 1996.
Issued in Renton, Washington, on March 1, 1996.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 96-5367 Filed 3-8-96; 8:45 am]
BILLING CODE 4910-13-U
