[Federal Register: October 1, 2003 (Volume 68, Number 190)]
[Proposed Rules]               
[Page 56596-56598]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr01oc03-35]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2001-NM-270-AD]
RIN 2120-AA64

 
Airworthiness Directives; BAE Systems (Operations) Limited 
(Jetstream) Model 4101 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 all BAE Systems (Operations) 
Limited (Jetstream) Model 4101 airplanes. This proposal would require 
various inspections of the fuselage nose structure between stations 4 
and 11, and corrective actions if necessary. This action is necessary 
to detect and correct fatigue cracking in the primary structure of the 
nose of the airplane at the forward avionics bay (fuselage stations 4 
to 11), which could result in reduced structural integrity of the 
airplane. This action is intended to address the identified unsafe 
condition.

DATES: Comments must be received by October 31, 2003.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2001-NM-270-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-270-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 or 2000 or 
ASCII text.
    The service information referenced in the proposed rule may be 
obtained from British Aerospace Regional Aircraft American Support, 
13850 Mclearen Road, Herndon, Virginia 20171. This information may be 
examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, 
SW., Renton, Washington.

FOR FURTHER INFORMATION CONTACT: Todd Thompson, Aerospace Engineer, 
International Branch, ANM-116, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
227-1175; fax (425) 227-1149.

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:
    [sbull] 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.
    [sbull] For each issue, state what specific change to the proposed 
AD is being requested.
    [sbull] 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 2001-NM-270-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-270-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The Civil Aviation Authority (CAA), which is the airworthiness 
authority for the United Kingdom, notified the FAA that an unsafe 
condition may exist on all BAE Systems (Operations) Limited (Jetstream) 
Model 4101 airplanes. The CAA advises that during an inspection done in 
accordance with Jetstream Service Bulletin J41-A53-023, referenced in 
AD 98-24-01, amendment 39-10888 (63 FR 63975, November 18, 1998), which 
addresses the diaphragms in the nose cone structure, operators found 
damage in diaphragms 14153005-177 and -178. When those diaphragms were 
removed to allow for replacement, fatigue cracking was found in the 
primary structure of the nose of the airplane at the forward avionics 
bay (fuselage stations 4 to 11). Such fatigue cracking, if not detected 
and corrected in a timely manner, could result in reduced structural 
integrity of the airplane.

Explanation of Relevant Service Information

    The manufacturer has issued Jetstream Service Bulletin J41-53-047, 
Revision 1, dated July 19, 2002, which describes procedures for various 
inspections of the fuselage nose structure between stations 4 and 11, 
and corrective actions, if necessary, as follows:
    [sbull] Repetitive detailed visual inspections of (1) the forward 
avionics bay doors for damage, and repair of damage within certain 
limits; (2) the cho-shield conductive coating for cracking, flaking, 
wearing, and any uneven surface; restoration of the coating, if 
necessary; and surface resistance tests of the coating; (3) the forward 
and rear faces of the station 4 bulkhead and the attached parts for 
damage, and repair of damage within certain limits; (4) all the 
aircraft

[[Page 56597]]

structure between the rear face of the station 4 bulkhead and station 8 
for damage, and repair of damage within certain limits; and (5) all the 
aircraft structure between stations 8 and 11 for damage, and repair of 
damage within certain limits.
    [sbull] Repetitive detailed visual inspections for cracks and 
corrosion of the surround structures for the avionics bay doors 
including the aft vertical closing frames, frame 8, upper gutters, 
corner gussets, and lower gutters.
    [sbull] Repetitive radiographic and eddy current inspections for 
cracks and corrosion of the avionics bay doors apertures including the 
door frames, gutters and corner gussets.
    [sbull] Repetitive radiographic and eddy current inspections of the 
high intensity radiated field (HIRF) seal at the avionics bay doors 
apertures for damage (including mechanical damage, corrosion, and 
exposure of the ferrex wire in the bulb of the seal), and replacement 
of the seal, if necessary; and surface resistance tests of the HIRF 
seal.
    Accomplishment of the actions specified in the service bulletin is 
intended to adequately address the identified unsafe condition. The CAA 
classified this service bulletin as mandatory and issued British 
airworthiness directive 001-06-2001 to ensure the continued 
airworthiness of these airplanes in the United Kingdom.

FAA's Conclusions

    This airplane model is manufactured in the United Kingdom and is 
type certificated for operation in the United States under the 
provisions of section 21.29 of the Federal Aviation Regulations (14 CFR 
21.29) and the applicable bilateral airworthiness agreement. Pursuant 
to this bilateral airworthiness agreement, the CAA has kept the FAA 
informed of the situation described above. The FAA has examined the 
findings of the CAA, reviewed all available information, and determined 
that AD action is necessary for products of this type design that are 
certificated for operation in the United States.

Explanation of Requirements of Proposed Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other airplanes of the same type design registered 
in the United States, the proposed AD would require accomplishment of 
the actions specified in the service bulletin described previously, 
except as discussed below.

Differences Between the Service Bulletin and This Proposed AD

    Operators should note that, although the Accomplishment 
Instructions of the referenced service bulletin describe procedures for 
submitting reports of inspection findings, this proposed AD would not 
require those actions. The FAA does not need this information from 
operators.
    Although the service bulletin describes a detailed visual 
inspection, this proposed AD would require a detailed inspection.
    Also, the service bulletin specifies that operators may contact the 
manufacturer for disposition of repairs, this proposal would require 
operators to repair per a method approved by either the FAA or the CAA 
(or its delegated agent). In light of the type of repair that would be 
required to address the unsafe condition, and consistent with existing 
bilateral airworthiness agreements, we have determined that, for this 
proposed AD, a repair approved by either the FAA or the CAA (or its 
delegated agent) would be acceptable for compliance with this proposed 
AD.
    The Planning Information in Jetstream Service Bulletin J41-53-047, 
Revision 1, dated July 19, 2002, states that operators may remove the 
HIRF seal and do a detailed visual inspection of the avionics bay door 
surround structure under the HIRF seal, or do a radiographic and eddy 
current inspection of the avionics bay door surround structure. The 
Accomplishment Instructions of the service bulletin do not specify that 
operators may choose which type of inspection to perform. This proposed 
AD clarifies that operators may choose to do either a detailed 
inspection or radiographic and eddy current inspections.

Changes to 14 CFR Part 39/Effect on the Proposed AD

    On July 10, 2002, the FAA issued a new version of 14 CFR part 39 
(67 FR 47997, July 22, 2002), which governs the FAA's airworthiness 
directives system. The regulation now includes material that relates to 
altered products, special flight permits, and alternative methods of 
compliance (AMOCs). Because we have now included this material in part 
39, only the office authorized to approve AMOCs is identified in each 
individual AD.

Explanation of Labor Rate Increase

    We have reviewed the figures we have used over the past several 
years to calculate AD costs to operators. To account for various 
inflationary costs in the airline industry, we find it necessary to 
increase the labor rate used in these calculations from $60 per work 
hour to $65 per work hour. The cost impact information, below, reflects 
this increase in the specified hourly labor rate.

Cost Impact

    The FAA estimates that 57 airplanes of U.S. registry would be 
affected by this proposed AD, that it would take approximately 50 work 
hours per airplane to accomplish the proposed inspection, and that the 
average labor rate is $65 per work hour. Based on these figures, the 
cost impact of the proposed AD on U.S. operators is estimated to be 
$185,250, or $3,250 per airplane, per inspection cycle.
    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 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.

[[Page 56598]]

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:

BAE Systems (Operations) Limited (Formerly British Aerospace 
Regional Aircraft): Docket 2001-NM-270-AD.

    Applicability: All Model Jetstream 4101 airplanes, certificated 
in any category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To detect and correct fatigue cracking in the primary structure 
of the nose of the airplane at the forward avionics bay (fuselage 
stations 4 to 11), which could result in reduced structural 
integrity of the airplane, accomplish the following:
    (a) Perform detailed, radiographic, and eddy current inspections 
of the fuselage nose structure between stations 4 and 11 for 
discrepancies (including cracking, corrosion, and exposed wiring), 
per the Accomplishment Instructions of Jetstream Service Bulletin 
J41-53-047, Revision 1, dated July 19, 2002, except that reporting 
results of inspection findings is not required by this AD. Do the 
inspections at the later of the times specified in paragraphs (a)(1) 
and (a)(2) of this AD. Repeat the inspections thereafter at 
intervals not to exceed 6,000 landings.
    (1) Prior to the accumulation of 10,000 total landings, but not 
before the accumulation of 7,000 total landings.
    (2) Within 3,000 landings after the effective date of this AD, 
or at the next 8-year environmental (corrosion) inspection, 
whichever occurs first.


    Note 1: 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.''


    (b) For the inspections of the surround structure for the 
avionics bay doors, operators may either remove the high intensity 
radiated field (HIRF) seal and do a detailed inspection, or do 
radiographic and eddy current inspections with the HIRF seal in 
place.
    (c) If any discrepancy is found during any inspection required 
by this AD, before further flight, repair per Jetstream Service 
Bulletin J41-53-047, Revision 1, dated July 19, 2002. Where the 
service bulletin specifies contacting the manufacturer for 
disposition of repairs, before further flight, repair per a method 
approved by the Manager, International Branch, ANM-116, FAA, 
Transport Airplane Directorate; or the Civil Aviation Authority (or 
its delegated agent).

Alternative Methods of Compliance

    (d) In accordance with 14 CFR 39.19, the Manager, International 
Branch, ANM-116, FAA, is authorized to approve alternative methods 
of compliance for this AD.


    Note 2: The subject of this AD is addressed in British 
airworthiness directive 001-06-2001.


    Issued in Renton, Washington, on September 24, 2003.
Ali Bahrami,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 03-24846 Filed 9-30-03; 8:45 am]

BILLING CODE 4910-13-P