[Federal Register: July 12, 2002 (Volume 67, Number 134)]
[Proposed Rules]               
[Page 46132-46134]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr12jy02-17]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2001-NM-192-AD]
RIN 2120-AA64

 
Airworthiness Directives; Boeing Model 757-200 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 757-200 
series airplanes. This proposal would require repetitive inspections 
for fatigue cracking of certain areas of the forward and aft frames of 
the cargo doors and repair, if necessary. This action is necessary to 
find and fix such cracking, which could lead to rapid depressurization 
of the airplane and result in reduced structural integrity of the cargo 
doorway. This action is intended to address the identified unsafe 
condition.

DATES: Comments must be received by August 26, 2002.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2001-NM-192-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. Comments may be submitted via fax to (425) 227-1232. 
Comments may also be sent via the Internet using the following address: 
9-anm-nprmcomment@faa.gov. Comments sent via fax or the Internet must 
contain ``Docket No. 2001-NM-192-AD'' in the subject line and need not 
be submitted in triplicate. Comments sent via the Internet as attached 
electronic files must be formatted in Microsoft Word 97 for Windows or 
ASCII text.
    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: Dennis Stremick, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
227-2776; 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 action may be changed in 
light of the comments received.
    Submit comments using the following format:
     Organize comments issue-by-issue. For example, discuss a 
request to change the compliance time and a request to change the 
service bulletin reference as two separate issues.
     For each issue, state what specific change to the proposed 
AD is being requested.
     Include justification (e.g., reasons or data) for each 
request.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of

[[Page 46133]]

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 action must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 2001-NM-192-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. 2001-NM-192-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The FAA has received a report indicating that, during fatigue 
testing of the fuselage of a Boeing Model 757 series airplane, 
extensive cracking in the web and inner and outer chords of the number 
1 and 2 cargo door frames was found. Subsequent to that testing, 
several reports were received from operators indicating cracking of the 
door frames on the number 1 and 2 cargo door frames on other Model 757 
series airplanes. Cracking of the frame web was found on four of those 
airplanes. All of the cracking occurred at, or slightly outboard of, 
door stop number 6. Inner chord cracking ranged from 0.12 to 3.0 
inches, and web cracking ranged from 0.40 inch to completely severed. 
The airplanes had accumulated between 22,199 and 27,528 flight cycles, 
and between 32,956 and 55,707 flight hours. Fatigue cracking of the 
cargo door frames, if not found and fixed, could lead to rapid 
depressurization of the airplane and result in reduced structural 
integrity of the cargo doorway.

Related Rulemaking

    This proposed AD is related to AD 86-17-05R1, amendment 5714 (52 FR 
32534, August 28, 1987), which is applicable to certain Boeing Model 
727 series airplanes. That AD requires repetitive inspections for 
cracking of cargo door frames and repair, if necessary. That AD also 
provides a modification as terminating action for the forward frame of 
the number 3 cargo door.
    This NPRM proposes similar actions for certain Boeing Model 757-200 
series airplanes because the number 3 cargo door is very similar to the 
number 3 cargo door on Model 727 series airplanes.

Explanation of Relevant Service Information

    The FAA has reviewed and approved Boeing Alert Service Bulletin 
757-53A0080, dated February 3, 2000, which describes procedures for 
repetitive detailed and high frequency eddy current inspections for 
cracking of the cargo door frames, and repair, if necessary. Group 1 
and 2 airplanes described in the service bulletin have only number 1 
and 2 cargo doors. Group 3 airplanes have an additional number 3 cargo 
door. The inspections include the frame webs, frame inner and outer 
chords, bear strap, and skin panels between the upper and lower sills 
of the cargo door. The service bulletin also describes procedures for 
detailed inspections for stringers 29R and 24R.
    The service bulletin describes procedures for repair of cracking 
that is confined to the frame webs. The service bulletin specifies 
contacting Boeing for repair information if any cracking is found in 
one of the frame chords, the bear strap, or the skin panel adjacent to 
the cargo doorway, or if damaged areas are outside specified limits. 
Accomplishment of the actions 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 require accomplishment of the actions specified in 
the service bulletin described previously, except as discussed below.

Differences Between This Proposed AD and the Service Information

    The compliance times specified in the tables in Section 1.E., 
Compliance, of the referenced service bulletin identify various 
inspection thresholds for doing the initial detailed and high frequency 
eddy current inspections, based on the number of flight cycles the 
airplane has accumulated (between 27,000 and 30,000). However, we have 
determined that the inspections required by this proposed AD must be 
done before the accumulation of 22,000 total flight cycles or within 
500 flight cycles after the effective date of the AD, whichever is 
later. This determination is based on fleet data received from the 
manufacturer which show that fatigue cracking of the frames on the 
cargo door occurred on affected airplanes that have accumulated between 
22,199 and 27,528 total flight cycles.
    Although the service bulletin specifies that the manufacturer may 
be contacted for disposition of certain repair conditions, this 
proposed AD would require the repair of those conditions to be 
accomplished in accordance with a method approved by the FAA, or in 
accordance with data meeting the type certification basis of the 
airplane approved by a Boeing Company Designated Engineering 
Representative who has been authorized by the FAA to make such 
findings.

Interim Action

    This is considered to be interim action. The manufacturer has 
advised that it currently is developing a modification that will 
address the unsafe condition identified in this AD. Once this 
modification is developed, approved, and available, the FAA may 
consider further rulemaking.

Cost Impact

    There are approximately 57 airplanes of the affected design in the 
worldwide fleet. The FAA estimates that 28 airplanes of U.S. registry 
would be affected by this proposed AD.
    For all airplanes it would take approximately 3 work hours per 
airplane to do the proposed high frequency eddy current and detailed 
inspections, at an average labor rate of $60 per work hour. Based on 
these figures, the cost impact of the inspections proposed by this AD 
on U.S. operators is estimated to be $5,040, or $180 per airplane, per 
inspection cycle.
    For Group 3 airplanes it would take approximately 1 work hour per 
airplane to do the proposed additional detailed inspection, at an 
average labor rate of $60 per work hour. Based on these figures, the 
cost impact of this proposed inspection on U.S. operators is estimated 
to be $60 per airplane, per inspection cycle.
    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 proposed AD were not adopted. The cost impact 
figures discussed in AD rulemaking actions represent only the time 
necessary to perform the specific actions actually required by the AD. 
These figures typically do not include incidental costs, such as the 
time required to gain access and close up,

[[Page 46134]]

planning time, or time necessitated by other administrative actions.

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 2001-NM-192-AD.

    Applicability: Model 757-200 series airplanes, line numbers 1 
through 57 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 (c) 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 find and fix fatigue cracking of the cargo door frames, which 
could lead to rapid depressurization of the airplane and result in 
reduced structural integrity of the cargo doorway, accomplish the 
following:

Repetitive Inspections

    (a) Before the accumulation of 22,000 total flight cycles or 
within 500 flight cycles after the effective date of this AD, 
whichever is later: Do the applicable inspections specified in 
paragraph (a)(1) and (a)(2) of this AD, per Boeing Alert Service 
Bulletin 757-53A0080, dated February 3, 2000.
    (1) For all airplanes: Do detailed and high frequency eddy 
current (HFEC) inspections for cracking of the door frames of the 
number 1 and 2 cargo doors (includes the frame webs, frame inner and 
outer chords, bear strap, and skin panels between the upper and 
lower sills of the cargo door). Repeat the detailed inspections 
every 3,000 flight cycles, and the HFEC inspections every 12,000 
flight cycles.
    (2) For Group 3 airplanes: Do a detailed inspection for cracking 
of the door frame of the number 3 cargo door. Repeat the inspection 
every 3,000 flight cycles.

    Note 2: For the purposes of this AD, a detailed 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.''

Repair

    (b) Before further flight, repair any cracking found in the 
frame webs per Boeing Alert Service Bulletin 757-53A0080, dated 
February 3, 2000. If any cracking is found in any other area and the 
service bulletin specifies to contact Boeing for disposition of 
those repairs, repair per a method approved by the Manager, Seattle 
Aircraft Certification Office (ACO), FAA; or per data meeting the 
type certification basis of the airplane approved by a Boeing 
Company Designated Engineering Representative (DER) who has been 
authorized by the Manager, Seattle ACO, to make such findings. For a 
repair method to be approved, the approval must specifically 
reference this AD.

    Note 3: There is no terminating action currently available for 
the repetitive inspections required by this AD.

Alternative Methods of Compliance

    (c) 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, FAA. 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 4: 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

    (d) 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 July 8, 2002.
Vi Lipski,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 02-17549 Filed 7-11-02; 8:45 am]
BILLING CODE 4910-13-U