[Federal Register Volume 67, Number 139 (Friday, July 19, 2002)]
[Proposed Rules]
[Pages 47491-47493]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 02-18213]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2002-NM-104-AD]
RIN 2120-AA64


Airworthiness Directives; Saab Model SAAB 2000, SAAB SF340A, and 
SAAB 340B Series 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 Saab Model SAAB 2000, SAAB 
SF340A, and SAAB 340B series airplanes. This proposal would require 
replacing the main pitot static tube on each side of the airplane with 
a new improved pitot static tube, and installing a gasket between the 
tube and the airplane structure. This action is necessary to prevent 
ice from blocking the pitot system, due to the pitot tube not having 
enough heating capacity to stay above freezing temperature, which could 
result in erroneous airspeed indications This action is intended to 
address the identified unsafe condition.

DATES: Comments must be received by August 19, 2002.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2002-NM-104-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. 2002-NM-104-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 Saab Aircraft AB, SAAB Aircraft Product Support, S-
581.88, Linkoping, Sweden. This information may be examined at the FAA, 
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington.

FOR FURTHER INFORMATION CONTACT: Dan Rodina, Aerospace Engineer, 
International Branch, ANM-116, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
227-2125; 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:
     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 2002-NM-104-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. 2002-NM-104-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The Luftfartsverket (LFV), which is the airworthiness authority for 
Sweden, notified the FAA that an unsafe condition may exist on all Saab 
Model SAAB 2000, SAAB SF340A, and SAAB 340B series airplanes. The LFV 
advises that operators have reported a number of events involving 
incorrect airspeed indications. A typical scenario is that, during 
descent from cruise altitude, one or more airspeed indicators 
incorrectly show gradually decreasing airspeed. At lower altitudes, the 
correct airspeed is again displayed, and on the ground, no faults can 
be found. System analysis indicates that, in the scenario described 
above, a freezing temperature is present in the pitot pressure lines 
inside the pitot static tube. This condition, if not corrected, could 
result in ice blocking the pitot system, due to the pitot tube not 
having enough heating capacity to stay above freezing temperature, 
which could result in erroneous airspeed indications.

Explanation of Relevant Service Information

    Saab has issued Service Bulletin 2000-34-060 (for Model SAAB 2000 
series airplanes) and Service Bulletin 340-34-145 (for Model SAAB 
SF340A and SAAB 340B series airplanes), both dated October 1, 2001, 
which describe procedures for replacing the main pitot static tube on 
each side of the airplane with a new improved pitot static tube with 
increased heating. The service bulletins also describe procedures for 
installing a new gasket between the tube

[[Page 47492]]

and the airplane structure that will increase thermal insulation. 
Accomplishment of the actions specified in the service bulletins is 
intended to adequately address the identified unsafe condition. The LFV 
classified these service bulletins as mandatory and issued Swedish 
airworthiness directive 1-166 (for all Model SAAB 2000 series 
airplanes), dated October 1, 2001; and Swedish airworthiness directive 
1-167 (for all Model SAAB SF340A and SAAB 340B series airplanes), dated 
October 1, 2001; in order to assure the continued airworthiness of 
these airplanes in Sweden.

FAA's Conclusions

    These airplane models are manufactured in Sweden and are 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 LFV has kept the FAA informed of 
the situation described above. The FAA has examined the findings of the 
LFV, 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.

Cost Impact

    The FAA estimates that 312 airplanes of U.S. registry would be 
affected by this proposed AD, that it would take approximately 8 work 
hours per airplane to accomplish the proposed replacement, and that the 
average labor rate is $60 per work hour. Required parts would cost 
approximately $13,400 per airplane. Based on these figures, the cost 
impact of the proposed AD on U.S. operators is estimated to be 
$4,330,560, or $13,880 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:

Saab Aircraft AB: Docket 2002-NM-104-AD.

    Applicability: All Model SAAB 2000, SAAB SF340A, and SAAB 340B 
series airplanes, 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 prevent ice from blocking the pitot system, due to the pitot 
tube not having enough heating capacity to stay above freezing 
temperature, which could result in erroneous airspeed indications, 
accomplish the following:

Replacement

    (a) Within 12 months from the effective date of this AD, replace 
the main pitot static tube on each side of the airplane with a new 
improved pitot static tube, and install a gasket between the tube 
and the airplane structure; per the Accomplishment Instructions of 
Saab Service Bulletin 340-34-145 (for Model 340A and 340B series 
airplanes) or Saab Service Bulletin 2000-34-060 (for Model 2000 
series airplanes), both dated October 1, 2001; as applicable.

Spares

    (b) As of the effective date of this AD, no person shall install 
any static pitot tube having part number 856ML1 or 856ML2, on any 
airplane.

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, International Branch, ANM-116, 
Transport Airplane Directorate, FAA. Operators shall submit their 
requests through an appropriate FAA Principal Maintenance Inspector, 
who may add comments and then send it to the Manager, International 
Branch, ANM-116.

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the International Branch, ANM-116.

Special Flight Permits

    (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.

    Note 3: The subject of this AD is addressed in Swedish 
airworthiness directives 1-166 and 1-167, both dated October 1, 
2001.



[[Page 47493]]


    Issued in Renton, Washington, on July 11, 2002.
Lirio Liu-Nelson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 02-18213 Filed 7-18-02; 8:45 am]
BILLING CODE 4910-13-P