[Federal Register Volume 66, Number 54 (Tuesday, March 20, 2001)]
[Proposed Rules]
[Pages 15662-15664]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-6792]


 ========================================================================
 Proposed Rules
                                                 Federal Register
 ________________________________________________________________________
 
 This section of the FEDERAL REGISTER contains notices to the public of 
 the proposed issuance of rules and regulations. The purpose of these 
 notices is to give interested persons an opportunity to participate in 
 the rule making prior to the adoption of the final rules.
 
 ========================================================================
 

  Federal Register / Vol. 66, No. 54 / Tuesday, March 20, 2001 / 
Proposed Rules  

[[Page 15662]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2000-NM-314-AD]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 747-100, -200B, -200F, -
200C, -100B, -300, -100B SUD, -400, -400D, -400F, and 747 SR Series 
Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

-----------------------------------------------------------------------

SUMMARY: This document proposes the adoption of a new airworthiness 
directive (AD) that is applicable to certain Boeing Model 747 series 
airplanes. This proposal would require repetitive inspections to find 
cracking of the frame web, strap, inner chords, and inner chord angle 
of the forward edge frame of the number 5 main entry door cutout, and 
repair, if necessary. This action is necessary to find and fix such 
cracking, which could result in severing of the frame, inability of the 
edge frame to react door stop loads, and consequent rapid 
depressurization of the airplane. This action is intended to address 
the identified unsafe condition.

DATES: Comments must be received by May 4, 2001.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2000-NM-314-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. Comments may be submitted via fax to (425) 227-1232. 
Comments may also be sent via the Internet using the following address: 
[email protected]. Comments sent via fax or the Internet must 
contain ``Docket No. 2000-NM-314-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: Rick Kawaguchi, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
227-1153; 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 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 2000-NM-314-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. 2000-NM-314-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The FAA has received reports indicating that cracking has been 
found in the frame strap and inner chord angle of the forward edge 
frame of the number 5 main entry door cutout at body station 2231 on 
several Boeing Model 747 series airplanes. The cracking originated at 
the fastener hole locations because of fatigue. Fatigue cracks in the 
frame web, strap, inner chords, and inner chord angle of the forward 
edge frame of the number 5 main entry door cutout, if not found, could 
extend to the inner chord of the frame and cause the inner chord to 
break, leading to failure of the outer chord and adjacent fuselage 
skin. This condition, if not corrected, could result in inability of 
the edge frame to react door stop loads, and consequent rapid 
depressurization of the airplane.

Explanation of Relevant Service Information

    The FAA has reviewed and approved Boeing Alert Service Bulletin 
747-53A2450, Revision 2, including Appendix A, dated January 4, 2001, 
which describes procedures for repetitive detailed visual, high 
frequency eddy current (HFEC), open hole HFEC, and low frequency eddy 
current inspections to find cracking of the frame web, strap, inner 
chords, and inner chord angle of the forward edge frame of the number 5 
main entry door cutout. If cracking is found, the service bulletin 
specifies to contact Boeing for repair instructions.

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

[[Page 15663]]

specified in the service bulletin described previously, except as 
discussed below.

Difference Between Service Bulletin and This Proposed AD

    The service bulletin specifies that the manufacturer must be 
contacted for repair of certain conditions, but this proposal would 
require the repair of those conditions to be accomplished per a method 
approved by the FAA; or per 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. For a method to be approved, the approval letter must 
specifically reference this AD.

Interim Action

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

Cost Impact

    There are approximately 1,314 airplanes of the affected design in 
the worldwide fleet. The FAA estimates that 258 airplanes of U.S. 
registry would be affected by this proposed AD, that it would take 
approximately 16 work hours per airplane to accomplish the proposed 
inspections, and that the average labor rate is $60 per work hour. 
Based on these figures, the cost impact of the proposed AD on U.S. 
operators is estimated to be $247,680 or $960 per airplane.
    The 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 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, 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 2000-NM-314-AD.

    Applicability: Model 747 series airplanes, as listed in Boeing 
Alert Service Bulletin 747-53A2450, Revision 2, dated January 4, 
2001, 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 cracking of the frame web, strap, inner chords, 
and inner chord angle of the forward edge frame of the number 5 main 
entry door cutout, which could result in severing of the frame, 
inability of the edge frame to react door stop loads, and consequent 
rapid depressurization of the airplane, accomplish the following:

Repetitive Inspections (No Terminating Action)

    (a) Inspect the airplane for cracks per Boeing Alert Service 
Bulletin 747-53A2450, Revision 2, including Appendix A, dated 
January 4, 2001; at the later of the times specified in either 
paragraph (a)(1) or (a)(2) of this AD, per Table 1 of this AD, as 
follows:

                    Table 1.--Inspection Requirements
------------------------------------------------------------------------
        Type of Inspection                     Area to inspect
------------------------------------------------------------------------
(1) Detailed Visual...............  Strap inner chords forward and aft
                                     of the web, and exposed web
                                     adjacent to the inner chords on
                                     station 2231 frame from stringer 23
                                     through 31 per Figure 5 or Figure 6
                                     of the service bulletin, as
                                     applicable.
(2) Surface High Frequency Eddy     Station 2231 inner chord angles at
 Current (HFEC).                     lower main sill interface per
                                     Figure 5 or Figure 6 of the service
                                     bulletin, as applicable.
(3) Open Hole HFEC................  Station 2231 frame fastener
                                     locations per Figures 4 and 7, and
                                     either Figure 5 or 6 of the service
                                     bulletin, as applicable.
(4) Surface HFEC..................  Around fastener locations on station
                                     2231 inner chords from stringer 23
                                     through 31 per Figure 5 or Figure 6
                                     of the service bulletin, as
                                     applicable.
(5) Low Frequency Eddy Current....  Station 2231 frame strap in areas
                                     covered by the reveal per Figure 5
                                     or Figure 6 of the service
                                     bulletin, as applicable.
------------------------------------------------------------------------


[[Page 15664]]

    (1) Where the compliance time in the logic diagram in Figure 1 
of Boeing Alert Service Bulletin 747-53A2450, Revision 2, dated 
January 4, 2001, specifies a compliance time beginning, ``from 
receipt of this service bulletin,'' this AD requires the compliance 
time begin ``after the effective date of this AD.'' Repeat the 
inspections after that at intervals not to exceed 3,000 flight 
cycles.
    (2) Within 3,000 flight cycles after accomplishment of the 
inspections specified in Figure 1 of Boeing Alert Service Bulletin 
747-53A2450, dated May 4, 2000, or Revision 1, dated July 6, 2000. 
Repeat the inspections after that at intervals not to exceed 3,000 
flight cycles.

    Note 2: There is no terminating action currently available for 
the inspections required by paragraph (a) of this AD.


    Note 3: Where there are differences between the AD and the alert 
service bulletin, the AD prevails.

Repair

    (b) If any cracking is found during any inspection required by 
paragraph (a) of this AD, before further flight, 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 who has been authorized by the Manager, Seattle ACO, 
to make such findings. For a repair method to be approved by the 
Manager, Seattle ACO, as required by this paragraph, the approval 
letter must specifically reference 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. 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 March 13, 2001.
Vi L. Lipski,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 01-6792 Filed 3-19-01; 8:45 am]
BILLING CODE 4910-13-U