[Federal Register Volume 63, Number 183 (Tuesday, September 22, 1998)]
[Rules and Regulations]
[Pages 50495-50498]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-25123]


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

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-NM-257-AD; Amendment 39-10786; AD 98-20-20]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 747 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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

SUMMARY: This amendment supersedes an existing airworthiness directive 
(AD), applicable to certain Boeing Model 747 series airplanes, that 
currently requires repetitive inspections for damage or cracking of the 
aft pressure bulkhead, and repair, if necessary. This amendment 
continues to require certain repetitive inspections for damage or 
cracking of the aft pressure bulkhead, and repair, if necessary. This 
amendment removes certain repetitive inspections for cracking of the 
bulkhead web to Y-ring lap joint area but retains the initial 
inspection for cracking in that area. This amendment also adds a one-
time inspection from the forward side of the bulkhead to detect fatigue 
cracking of the upper segment of the bulkhead web, and follow-on 
corrective actions, if necessary. This amendment is prompted by reports 
indicating that the inspections required by the existing AD may not 
detect cracking of the bulkhead web in a timely manner. The actions 
specified in this AD are intended to detect and correct fatigue 
cracking of the upper segment of the bulkhead web, which could result 
in rapid depressurization of the airplane, and consequent reduced 
controllability of the airplane.

DATES: Effective October 7, 1998. The incorporation by reference of 
certain publications listed in the regulations is approved by the 
Director of the Federal Register as of October 7, 1998.
    Comments for inclusion in the Rules Docket must be received on or 
before November 23, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 98-NM-257-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056.
    The service information referenced in this AD 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; or at 
the Office of the Federal Register, 800 North Capitol Street, NW., 
suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Bob Breneman, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Transport Airplane Directorate, Seattle 
Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, 
Washington 98055-4056; telephone (425) 227-2776; fax (425) 227-1181.

SUPPLEMENTARY INFORMATION: On October 21, 1987, the FAA issued AD 87-
23-10, amendment 39-5758 (52 FR 41551, October 29, 1987), applicable to 
certain Boeing Model 747 series airplanes, to require repetitive 
inspections for damage or cracking of the aft pressure bulkhead, and 
repair, if necessary. That action was prompted by analysis of 
inspection reports and the results of testing by the manufacturer. The 
actions required by that AD are intended to detect and correct fatigue 
cracking of the aft pressure bulkhead, which could result in rapid 
depressurization of the airplane.

Actions Since Issuance of Previous Rule

    Since the issuance of that AD, the FAA has received a report 
indicating that one operator found a 7.5-inch-long crack in the upper 
portion of the web of the pressure bulkhead at Body Station 2360 on a 
Boeing Model 747 series airplane. Analysis of the cracked bulkhead web 
revealed a series of short cracks initiated at the fastener holes 
common to the outer chord of the Y-ring in multiple locations. These 
cracks propagated rapidly due to fatigue, and joined together to form 
the 7.5-inch-long crack.
    That airplane had accumulated 25,777 total landings and 74,266 
total flight hours at the time the crack was discovered. The upper 
portion of the web of the pressure bulkhead of that airplane had been 
inspected previously in accordance with AD 87-23-10, and the crack was 
discovered during a repeat detailed visual inspection performed 
approximately 7,000 landings after the initial inspection. These 
findings indicate that cracking of the upper portion of the web of the 
pressure bulkhead could develop on the affected airplanes in fewer 
landings than the repetitive inspection interval of 7,000 landings that 
is mandated by the existing AD.

Explanation of Relevant Service Information

    The FAA has reviewed and approved Boeing Alert Service Bulletin 
747-53A2275, Revision 6, dated August 27, 1998. That alert service 
bulletin describes procedures for, among other things, a detailed 
visual inspection performed from the forward side of the bulkhead to 
detect cracking of the upper segment of the bulkhead web at the 
attachment to the outer chord of the Y-ring. That alert service 
bulletin also describes procedures for follow-on corrective actions, if 
necessary, which include a surface probe eddy current inspection to 
detect cracking of the upper and lower segments of the bulkhead around 
the fasteners that attach the web to the outer chord of the Y-ring. The 
alert service bulletin also specifies that the manufacturer may be 
contacted for the disposition of certain repairs.

Explanation of Requirements of Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other airplanes of this same type design, this AD 
supersedes AD 87-23-10 to continue to require certain repetitive 
inspections for damage or cracking of the aft pressure bulkhead, and 
repair, if necessary. In addition, this AD removes repetitive detailed 
visual inspections for cracking of the bulkhead web to Y-ring lap joint 
area but retains the initial inspection for cracking in that area. This 
AD also adds a one-time detailed visual inspection from the forward 
side of the bulkhead to detect fatigue cracking of the upper segment of 
the bulkhead web, and follow-on corrective actions, if necessary. The 
actions are required to be accomplished

[[Page 50496]]

in accordance with the alert service bulletin described previously, 
except as discussed below.

Interim Action

    This is considered to be interim action. The FAA is currently 
considering requiring additional repetitive detailed visual inspections 
from the forward side of the bulkhead to detect cracking of the upper 
segment of the bulkhead web; repetitive surface probe high frequency 
eddy current inspections from the forward side of the bulkhead to 
detect cracking of the upper and lower segments of the bulkhead web; 
and repair, if necessary. However, the planned compliance time for 
these actions is sufficiently long so that notice and opportunity for 
prior public comment will be practicable.

Differences Between Alert Service Bulletin and This AD

    Operators should note that, although the alert service bulletin 
specifies that the manufacturer may be contacted for disposition of 
certain repair conditions, this AD requires 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.
    Operators also should note that the alert service bulletin 
specifies accomplishment of the visual inspection prior to the 
accumulation of 20,000 total flight cycles (landings); within 250 
flight cycles after receipt of Boeing Alert Service Bulletin 747-
53A2275, Revision 6; or within 1,500 flight cycles after the last 
visual inspection from the forward side of the bulkhead; whichever 
occurs latest. The FAA has determined that such compliance options may 
not ensure that all affected airplanes are inspected in a timely 
manner.
    In developing an appropriate compliance time for this AD, the FAA 
considered not only the manufacturer's recommendation, but also the 
time necessary to accomplish the inspection (4 hours), and the average 
utilization of the affected fleet. The FAA finds that, due to possible 
variances in average utilization among airplanes, a grace period of 90 
days rather than 250 flight cycles (landings) will better ensure that 
the inspection is accomplished on all Boeing Model 747 series airplanes 
in a timely manner.
    In light of all of these factors, the FAA finds that accomplishment 
of the inspection for all affected airplanes prior to the accumulation 
of 20,000 total landings, within 1,500 landings after the last visual 
inspection from the forward side of the bulkhead, or within 90 days 
after the effective date of this AD, whichever occurs latest, 
represents an appropriate interval of time allowable for affected 
airplanes to continue to operate without compromising safety.

Explanation of Applicability

    AD 87-23-10 was applicable to Boeing Model 747 series airplanes, as 
listed in Boeing Service Bulletin 747-53-2275, Revision 1, dated August 
13, 1987. This AD is applicable to Boeing Model 747 series airplanes, 
line positions 1 through 671. This change is being made to more 
precisely define the airplanes that are affected. The line positions 
are the same as those referenced in the effectivity of Boeing Service 
Bulletin 747-53-2275, Revision 1; no new airplanes are added as a 
result of this change.

Explanation of Disallowance of Adjustment Factor

    Paragraph (g) of AD 87-23-10 specified that, based on continued 
mixed operation at lower cabin differential pressures, the compliance 
thresholds and intervals specified in that AD for Boeing Model 747 
series airplanes could be multiplied by a 1.2 adjustment factor. Since 
the issuance of that AD, the FAA has determined that insufficient data 
exist to support such an adjustment to flight cycles. In fact, data are 
available that indicate that the use of a 1.2 adjustment factor 
provides inaccurate data and unjustified relief for inspection 
intervals. Consequently, this AD does not allow for such an adjustment 
factor, and the provisions of paragraph (g) of the existing AD have not 
been included in this AD.

Explanation of Disallowance of Modification

    Paragraph (j) of AD 87-23-10 specifies that modification of Boeing 
Model 747 series airplanes by installing certain new, improved parts 
would constitute terminating action for the inspection requirements of 
that AD. Since the issuance of AD 87-23-10, the FAA has determined that 
the kit necessary for accomplishment of such modification was never 
made available by the manufacturer. Therefore, because it is not 
possible to comply with the actions described by paragraph (j), the 
provisions of that paragraph have not been included in this AD.

Determination of Rule's Effective Date

    Since a situation exists that requires the immediate adoption of 
this regulation, it is found that notice and opportunity for prior 
public comment hereon are impracticable, and that good cause exists for 
making this amendment effective in less than 30 days.

Comments Invited

    Although this action is in the form of a final rule that involves 
requirements affecting flight safety and, thus, was not preceded by 
notice and an opportunity for public comment, comments are invited on 
this rule. Interested persons are invited to comment on this 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 under the caption ADDRESSES. All 
communications received on or before the closing date for comments will 
be considered, and this rule may be amended in light of the comments 
received. Factual information that supports the commenter's ideas and 
suggestions is extremely helpful in evaluating the effectiveness of the 
AD action and determining whether additional rulemaking action would be 
needed.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the rule that might 
suggest a need to modify the 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 that 
summarizes each FAA-public contact concerned with the substance of this 
AD will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this rule must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 98-NM-257-AD.'' The postcard will be date stamped and 
returned to the commenter.

Regulatory Impact

    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.
    The FAA has determined that this regulation is an emergency 
regulation that must be issued immediately to correct an unsafe 
condition in aircraft,

[[Page 50497]]

and that it is not a ``significant regulatory action'' under Executive 
Order 12866. It has been determined further that this action involves 
an emergency regulation under DOT Regulatory Policies and Procedures 
(44 FR 11034, February 26, 1979). If it is determined that this 
emergency regulation otherwise would be significant under DOT 
Regulatory Policies and Procedures, a final regulatory evaluation will 
be prepared and placed in the Rules Docket.
    A copy of it, if filed, 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 U.S.C. 106(g), 40113, 44701.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by removing amendment 39-5758 (52 FR 
41551, October 29, 1987), and by adding a new airworthiness directive 
(AD), amendment 39-10786, to read as follows:

98-20-20  Boeing: Amendment 39-10786. Docket 98-NM-257-AD. 
Supersedes AD 87-23-10, amendment 39-5758.

    Applicability: Model 747 series airplanes, line positions 1 
through 671 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 (i)(1) 
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 detect and correct fatigue cracking of the upper segment of 
the bulkhead web, which could result in rapid depressurization of 
the airplane, and consequent reduced controllability of the 
airplane, accomplish the following:
    (a) Within 750 landings after December 10, 1987 (the effective 
date for AD 87-23-10, amendment 39-5758), unless accomplished within 
the last 1,250 landings [for airplanes subject to a 2,000-landing 
repeat inspection interval in accordance with paragraph (b) of this 
AD], or unless accomplished within the last 250 landings [for 
airplanes subject to a 1,000-landing repeat inspection interval in 
accordance with paragraph (b) of this AD], perform a detailed visual 
inspection; in accordance with Boeing Service Bulletin 747-53-2275, 
dated March 26, 1987, Revision 1, dated August 13, 1987, Revision 2, 
dated March 31, 1988, Revision 3, dated March 29, 1990, Revision 4, 
dated March 26, 1992, or Revision 5, dated January 16, 1997, or 
Boeing Alert Service Bulletin 747-53A2275, Revision 6, dated August 
27, 1998; of the aft side of the entire Body Station (BS) 2360 aft 
pressure bulkhead for damage such as dents, tears, nicks, gouges, or 
scratches; and cracks at splices and doublers, and around the 
Auxiliary Power Unit pressure pan cutout; and, for Group 4 airplanes 
only, inspect from the forward side, the area adjacent to the window 
cutout for damage or cracks.

    Note 2: Notwithstanding provisions to the contrary in AD 87-23-
10, and in Boeing Service Bulletin 747-53-2275, dated March 26, 
1987, Revision 1, dated August 13, 1987, Revision 2, dated March 31, 
1988, Revision 3, dated March 29, 1990, Revision 4, dated March 26, 
1992, and Revision 5, dated January 16, 1997: For Model 747SR 
airplanes operating at a cabin pressure differential lower than 8.6 
pounds-per-square-inch (psi), an adjustment factor of 1.2 shall not 
be used after the effective date of this AD as a multiplier for 
inspection thresholds and intervals specified in this AD.
    (b) After initial compliance with paragraph (a) of this AD, 
continue to inspect as follows:
    (1) For Group 1 airplanes, repeat the inspections required by 
paragraph (a) of this AD, at intervals not to exceed 2,000 landings.
    (2) For Groups 2 and 3 airplanes, repeat the inspections 
required by paragraph (a) of this AD, at intervals not to exceed 
1,000 landings; or optionally, at the applicable time specified in 
paragraph (b)(2)(i) or (b)(2)(ii) of this AD.
    (i) For Group 2 airplanes that operate the entire interval with 
aft lavatory complexes or galleys adjacent to bulkheads, repeat the 
inspections required by paragraph (a) of this AD at intervals not to 
exceed 2,000 landings.
    (ii) For Groups 2 and 3 airplanes that operate the entire 
interval with an intact protective shield on the lower half of the 
forward side of the bulkhead, repeat the inspections required by 
paragraph (a) of this AD at intervals not to exceed 2,000 landings; 
and perform a detailed visual inspection of the protective shield 
for damage in accordance with Boeing Service Bulletin 747-53-2275, 
dated March 26, 1987, Revision 1, dated August 13, 1987, Revision 2, 
dated March 31, 1988, Revision 3, dated March 29, 1990, Revision 4, 
dated March 26, 1992, or Revision 5, dated January 16, 1997, or 
Boeing Alert Service Bulletin 747-53A2275, Revision 6, dated August 
27, 1998, at intervals not to exceed 1,000 landings. If damage is 
found to the protective shield that exceeds the limits indicated in 
the service bulletin, prior to further flight, repeat the inspection 
required by paragraph (a) of this AD.
    (3) For Group 4 airplanes, repeat the inspections required by 
paragraph (a) of this AD at intervals not to exceed 1,000 landings.
    (c) Within 750 landings after December 10, 1987, or prior to the 
accumulation of 20,000 total landings, whichever occurs later, 
unless accomplished within the last 3,250 landings; and at intervals 
thereafter not to exceed 4,000 landings; perform eddy current, 
ultrasonic, and X-ray inspections of the aft side of the BS 2360 aft 
pressure bulkhead for cracks; in accordance with Boeing Service 
Bulletin 747-53-2275, dated March 26, 1987, Revision 1, dated August 
13, 1987, Revision 2, dated March 31, 1988, Revision 3, dated March 
29, 1990, Revision 4, dated March 26, 1992, or Revision 5, dated 
January 16, 1997, or Boeing Alert Service Bulletin 747-53A2275, 
Revision 6, dated August 27, 1998.
    (d) Within 750 landings after December 10, 1987, or prior to the 
accumulation of 20,000 total landings, whichever occurs later, 
unless accomplished within the last 6,250 landings; and thereafter 
at intervals not to exceed 7,000 landings until the inspection 
required by paragraph (g) of this AD is accomplished: Perform a 
detailed visual inspection to detect cracking of the BS 2360 aft 
pressure bulkhead web to Y-ring lap joint area between radial 
stiffeners from the forward side of the bulkhead, in accordance with 
Boeing Service Bulletin 747-53-2275, dated March 26, 1987, Revision 
1, dated August 13, 1987, Revision 2, dated March 31, 1988, Revision 
3, dated March 29, 1990, Revision 4, dated March 26, 1992, or 
Revision 5, dated January 16, 1997, or Boeing Alert Service Bulletin 
747-53A2275, Revision 6, dated August 27, 1998.
    (e) If any cracking or damage is found during any inspection 
required by paragraph (a), (b), (c), or (d) of this AD, repair prior 
to further flight in accordance with Boeing Service Bulletin 747-53-
2275, dated March 26, 1987, Revision 1, dated August 13, 1987, 
Revision 2, dated March 31, 1988, Revision 3, dated March 29, 1990, 
Revision 4, dated March 26, 1992, or Revision 5, dated January 16, 
1997, or Boeing Alert Service Bulletin 747-53A2275, Revision 6, 
dated August 27, 1998.
    (f) For the purpose of complying with this AD, the number of 
landings may be determined to equal the number of pressurization 
cycles where the cabin pressure differential was greater than 2.0 
psi.
    (g) Perform a one-time detailed visual inspection from the 
forward side of the bulkhead of the upper segment of the bulkhead 
web at BS 2360 to detect cracking, in accordance with Boeing Alert 
Service Bulletin 747-53A2275, Revision 6, dated August 27, 1998, at 
the earlier of the times specified in paragraphs (g)(1) and (g)(2) 
of this AD. If no cracking is detected during this inspection, no 
further action is required by this paragraph. Accomplishment of this 
inspection terminates the repetitive inspection requirement of 
paragraph (d) of this AD.

[[Page 50498]]

    (1) Within 7,000 landings after the most recent detailed visual 
inspection accomplished in accordance with paragraph (d) of this AD.
    (2) At the latest of the times specified in paragraphs 
(g)(2)(i), (g)(2)(ii), and (g)(2)(iii) of this AD.
    (i) Prior to the accumulation of 20,000 total landings.
    (ii) Within 1,500 landings after the most recent detailed visual 
inspection accomplished in accordance with paragraph (d) of this AD.
    (iii) Within 90 days after the effective date of this AD.
    (h) If any cracking is detected during the inspection required 
by paragraph (g) of this AD, prior to further flight, accomplish a 
surface probe eddy current inspection from the forward side of the 
bulkhead to detect cracking of the upper and lower segments of the 
bulkhead web around the fasteners that attach the web to the outer 
chord of the Y-ring, in accordance with Boeing Alert Service 
Bulletin 747-53A2275, Revision 6, dated August 27, 1998. Repair any 
cracking, prior to further flight, in accordance with a method 
approved by the Manager, Seattle Aircraft Certification Office 
(ACO), FAA, Transport Airplane Directorate; 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 Manager, Seattle ACO, to make such findings.
    (i)(1) 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.
    (i)(2) Alternative methods of compliance for repairs and 
modifications, approved previously in accordance with AD 87-23-10, 
amendment 39-5758, are approved as alternative methods of compliance 
with this AD.

    Note 3: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Seattle ACO.

    (j) 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.
    (k) Except as provided by paragraph (h) of this AD, the actions 
shall be done in accordance with Boeing Service Bulletin 747-53-
2275, dated March 26, 1987, Revision 1, dated August 13, 1987, 
Revision 2, dated March 31, 1988, Revision 3, dated March 29, 1990, 
Revision 4, dated March 26, 1992, or Revision 5, dated January 16, 
1997, or Boeing Alert Service Bulletin 747-53A2275, Revision 6, 
dated August 27, 1998. These Boeing service bulletins contain the 
following list of effective pages:

----------------------------------------------------------------------------------------------------------------
  Service bulletin referenced and                           Revision level shown                                
               date                        Page No.                on page               Date shown on page     
----------------------------------------------------------------------------------------------------------------
747-53-2275, March 26, 1987.......  1-50.................  Original..............  March 26, 1987.              
747-53-2275, Revision 1, August     1-8, 10-17, 26-51....  1.....................  August 13, 1987.             
 13, 1987.                                                                                                      
                                    9, 18-25.............  Original..............  March 26, 1987.              
747-53-2275, Revision 2, March 31,  1-8, 10-13, 18, 22,    2.....................  March 31, 1988.              
 1998.                               29, 35, 42, 49-53.                                                         
                                    14-17, 26-28, 30-34,   1.....................  August 13, 1987.             
                                     36-41, 43-38.                                                              
                                    9, 19-21, 23-25......  Original..............  March 26, 1987.              
747-53-2275, Revision 3, March 29,  1-33, 35, 54-57......  3.....................  March 29, 1990.              
 1990.                                                                                                          
                                    42, 49-53............  2.....................  March 31, 1988.              
                                    34, 36-41, 43-48.....  1.....................  August 13, 1987.             
747-53-2275, Revision 4, March 26,  1-60.................  4.....................  March 26, 1992.              
 1992.                                                                                                          
747-53-2275, Revision 5, January    1-66.................  5.....................  January 16, 1997.            
 16, 1997.                                                                                                      
747-53A2275, Revision 6, August     1-76.................  6.....................  August 27, 1997.             
 27, 1997.                                                                                                      
----------------------------------------------------------------------------------------------------------------

    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.
    (l) This amendment becomes effective on October 7, 1998.

    Issued in Renton, Washington, on September 14, 1998.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 98-25123 Filed 9-21-98; 8:45 am]
BILLING CODE 4910-13-P