[Federal Register Volume 62, Number 198 (Tuesday, October 14, 1997)]
[Proposed Rules]
[Pages 53272-53274]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-27091]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97-NM-127-AD]
RIN 2120-AA64


Airworthiness Directives; British Aerospace (Jetstream) Model 
4101 Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes to revise an existing airworthiness 
directive (AD), applicable to certain British Aerospace (Jetstream) 
Model 4101 airplanes, that currently requires an inspection to 
determine the thickness of the intercostal that attaches the third crew 
member seat to the floor structure in the flight compartment, and 
replacement, if necessary. That AD was prompted by a report from the 
manufacturer indicating that intercostals have been installed that are 
not of sufficient thickness (and consequent strength) to support the 
third crew member seat during emergency landing dynamic conditions. The 
actions specified by that AD are intended to prevent the failure of 
this intercostal during an emergency landing, which could consequently 
result in injury to the flight crew. This action would revise the 
applicability of the existing AD by removing several airplanes.

DATES: Comments must be received by November 10, 1997.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 97-NM-127-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.
    The service information referenced in the proposed rule may be 
obtained from AI(R) American Support, Inc., 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: William Schroeder, Aerospace Engineer, 
Standardization Branch, ANM-113, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
227-2148; 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 notice may be changed in 
light of the comments received.
    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 notice must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 97-NM-127-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-103, Attention: Rules 
Docket No. 97-NM-127-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    On May 12, 1997, the FAA issued AD 97-11-02, amendment 39-10031 (62 
FR 28795, May 28, 1997), applicable to certain British Aerospace 
(Jetstream) Model 4101 airplanes, to require a one-time inspection to 
determine the thickness of the intercostal that attaches the third crew 
member seat to the floor structure in the flight compartment to 
determine the thickness of this part, and replacement with a new 
intercostal of the correct thickness, if necessary. That action was 
prompted by a report from the manufacturer indicating that intercostals 
have been installed that are not of sufficient thickness (and 
consequent strength) to support the third crew member seat during 
emergency landing dynamic conditions. The requirements of that AD are 
intended to prevent the failure of this intercostal during an emergency 
landing, which could consequently result in injury to the flight crew.

Actions Since Issuance of Previous Rule

    Since the issuance of that AD, the manufacturer has issued Alert 
Service Bulletin J41-A53-030, Revision 1, dated August 8, 1996, and 
Revision 2, dated February 14, 1997. The inspection and replacement 
procedures described in these revisions are identical to those 
described in the original version of the service bulletin (which was 
referenced in AD 97-11-02). The only change effected by Revisions 1 and 
2 is to remove airplanes having constructors numbers 41044, 41068, 
41069, and 41070 from the effectivity listing of the alert service 
bulletin, since these airplanes are not subject to the addressed unsafe 
condition. The Civil Aviation Authority (CAA), which is the 
airworthiness authority for the United Kingdom, classified these alert 
service bulletins as mandatory.
    The FAA has been advised that Jetstream Aircraft Limited has 
revised its corporate name to British Aerospace Regional Aircraft.

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 Sec. 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

[[Page 53273]]

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 revise AD 97-11-02 to 
continue to require a one-time inspection of the intercostal of the 
third crew member seat to the floor structure in the flight compartment 
to determine the thickness of this part, and replacement with a new 
intercostal of the correct thickness, if necessary. The proposed AD 
also would limit the applicability of the existing AD by removing 
several airplanes.

Cost Impact

    Since this proposed AD would merely delete airplanes from the 
applicability of the existing AD, it would add no additional costs, and 
would require no additional work to be performed by affected operators. 
The current costs associated with this AD are reiterated in their 
entirety (as follows) for the convenience of affected operators:
    The FAA estimates that 14 Jetstream Model 4101 airplanes of U.S. 
registry would be affected by this proposed AD, that it would take 
approximately 1 work hour per airplane to accomplish the proposed 
actions, 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 $840, or $60 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 AD were not adopted.

Regulatory Impact

    The regulations proposed herein would 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 
proposal would not have sufficient federalism implications to warrant 
the preparation of a Federalism Assessment.
    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 removing amendment 39-10031 (62 FR 
28795, May 28, 1997), and by adding a new airworthiness directive (AD), 
to read as follows:

British Aerospace Regional Aircraft [Formerly Jetstream Aircraft 
Limited; British Aerospace (Commercial Aircraft) Limited]: Docket 
97-NM-127-AD. Revises AD 97-11-02, Amendment 39-10031.

    Applicability: Jetstream Model 4101 airplanes, as listed in 
Jetstream Alert Service Bulletin J41-A53-030, Revision 2, dated 
February 14, 1997; certificated in any category.

    Note: This AD applies to each airplane identified in the 
preceding applicability provision, regardless of whether it has been 
otherwise 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 (d) 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 prevent failure during emergency landing dynamic conditions 
of the intercostal that attaches the third crew member seat (``third 
crew seat'') to the floor structure in the flight compartment, which 
could consequently result in injury to the flight crew, accomplish 
the following:
    (a) Within 30 days after July 2, 1997 (the effective date of AD 
97-11-02, amendment 39-10031), inspect the intercostal in the floor 
structure that supports the third crew seat in the flight 
compartment to determine the thickness of this part, in accordance 
with Part 1 of Jetstream Alert Service Bulletin J41-A53-030, dated 
January 19, 1996, Revision 1, dated August 8, 1996, or Revision 2, 
dated February 14, 1997.
    (b) If the thickness of the intercostal is 0.064 inch, no 
further action is required by this AD.
    (c) If the thickness of the intercostal is 0.048 inch, 
accomplish the actions specified in either paragraph (c)(1) or 
(c)(2) of this AD.
    (1) Prior to further flight, replace the intercostal with a new 
part manufactured from material having the correct thickness, in 
accordance with Jetstream Alert Service Bulletin J41-A53-030, dated 
January 19, 1996, Revision 1, dated August 8, 1996, or Revision 2, 
dated February 14, 1997. After replacement, no further action is 
required by this AD. Or
    (2) Prior to further flight, install a placard, in accordance 
with Jetstream Alert Service Bulletin J41-A53-030, dated January 19, 
1996, Revision 1, dated August 8, 1996, or Revision 2, dated 
February 14, 1997, to prohibit use of the third crew seat when the 
total weight of carry-on items stored in the forward right stowage 
area is more than 100 pounds. Within 6 months after installation of 
the placard, replace the intercostal with a new part manufactured 
from material having the correct thickness, in accordance with any 
of the service bulletins. After installation of the new intercostal, 
the placard may be removed.
    (d) 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, Standardization Branch, ANM-113, 
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, 
Standardization Branch, ANM-113.

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Standardization Branch, ANM-113.

    (e) 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.


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    Issued in Renton, Washington, on October 7, 1997.
James V. Devany,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 97-27091 Filed 10-10-97; 8:45 am]
BILLING CODE 4910-13-P