[Federal Register Volume 60, Number 51 (Thursday, March 16, 1995)]
[Proposed Rules]
[Pages 14237-14238]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-6469]



[[Page 14237]]


DEPARTMENT OF TRANSPORTATION

14 CFR Part 39

[Docket No. 95-NM-17-AD]


Airworthiness Directives; 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 certain Jetstream Model 4101 
airplanes. This proposal would require replacement of a certain 
pressure switch with a certain new pressure switch in the fuel system 
for the engines. This proposal is prompted by a report indicating that 
the current design of a certain pressure switch in the fuel system for 
the engines does not meet current fire resistant properties, which 
could result in the failure of the pressure switch during a fire in the 
engine compartment. The actions specified by the proposed AD are 
intended to prevent failure of the existing pressure switch in the fuel 
system for the engines, which, during an engine fire, could result in 
fuel leakage that could add fuel to the fire.

DATES: Comments must be received by April 10, 1995.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 95-NM-17-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 Jetstream Aircraft, Inc., P.O. Box 16029, Dulles 
International Airport, Washington, DC 20041-6029. 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 (206) 
227-2148; fax (206) 227-1320.

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 95-NM-17-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. 95-NM-17-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The Civil Aviation Authority (CAA), which is the airworthiness 
authority for the United Kingdom, recently notified the FAA that an 
unsafe condition may exist on certain Jetstream Model 4101 airplanes. 
The CAA advises that, during a design review of the fuel system, the 
manufacturer determined that the current design of the pressure switch 
having part number (P/N) 1153P0073 in the fuel system of the left and 
right engine does not meet the fire resistant properties, as required 
by section 25.1183 (a) of the Federal Aviation Regulations (14 CFR 
25.1183), ``Flammable fluid-carrying components.''
    If a fire in the engine compartment occurred, the existing pressure 
switch in the fuel system for the left and right engine could fail. If 
the pressure switch fails, fuel leakage could occur during an engine 
fire, which could add fuel to the fire.
    Jetstream has issued Service Bulletin J41-73-007, dated November 
22, 1994, which describes procedures for replacement of the pressure 
switch having P/N 1153P0073 with a new pressure switch having P/N 
1153P0094 in the fuel system for the left and right engines. The new 
pressure switch has been redesigned to meet the fire resistance 
requirements of section 25.1183(a) of the Federal Aviation Regulations 
[14 CFR 25.1183 (a)]. The pressure switch provides a warning to the 
flight crew if fuel filter blockage begins to occur. The CAA classified 
this service bulletin as mandatory in order to assure the continued 
airworthiness of these airplanes in the United Kingdom.
    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.
    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 replacement of a 
certain pressure switch with a certain new pressure switch in the fuel 
system of the left and right engine. The actions would be required to 
be accomplished in accordance with the service bulletin described 
previously.
    As a result of recent communications with the Air Transport 
Association (ATA) of America, the FAA has learned that, in general, 
some operators may misunderstand the legal effect of AD's on airplanes 
that are identified in the applicability provision of the AD, but that 
have been altered or repaired in the area addressed by the AD. The FAA 
points out that all airplanes identified in the applicability provision 
of an AD are legally subject to the AD. If an airplane has been altered 
or repaired in the affected area in such a way as to affect compliance 
with the AD, the owner or operator is required to obtain FAA approval 
for an alternative method of compliance with the AD, in accordance with 
the paragraph of each AD that provides for such approvals. A note has 
been included in this notice to clarify this long standing requirement.
    The FAA estimates that 15 airplanes of U.S. registry would be 
affected by this proposed AD, that it would take 
[[Page 14238]] approximately 3 work hours per airplane to accomplish 
the proposed actions, and that the average labor rate is $60 per work 
hour. Required parts would be supplied by the manufacturer at no cost 
to the operators. Based on these figures, the total cost impact of the 
proposed AD on U.S. operators is estimated to be $2,700, or $180 per 
airplane.
    The total 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 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. App. 1354(a), 1421 and 1423; 49 U.S.C. 
106(g); and 14 CFR 11.89.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by adding the following new 
airworthiness directive:

Jetstream Aircraft Limited: Docket 95-NM-17-AD.

    Applicability: Model 4101 airplanes, constructors numbers 41004 
through 41046 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 use the authority 
provided in paragraph (c) to request approval from the FAA. This 
approval may address either no action, if the current configuration 
eliminates the unsafe condition; or different actions necessary to 
address the unsafe condition described in this AD. Such a request 
should include an assessment of the effect of the changed 
configuration on the unsafe condition addressed by this AD. In no 
case does the presence of any modification, alteration, or repair 
remove any airplane from the applicability of this AD.

    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent failure of the existing pressure switch in the fuel 
system of the left and right engine, which, during an engine fire, 
could result in fuel leakage that could add fuel to the fire, 
accomplish the following:
    (a) Within 60 days after the effective date of this AD, replace 
pressure switch having part number (P/N) 1153P0073 with a new 
pressure switch having P/N 1153P0094 in the fuel system of the left 
and right engine, in accordance with Jetstream Service Bulletin J41-
73-007, dated November 22, 1994.
    (b) As of the effective date of this AD, no person shall install 
a pressure switch, P/N 1153P0073, on any airplane.
    (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, 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.

    (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 10, 1995.
Neil D. Schalekamp,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 95-6469 Filed 3-15-95; 8:45 am]
BILLING CODE 4910-13-U