[Federal Register Volume 61, Number 180 (Monday, September 16, 1996)]
[Rules and Regulations]
[Pages 48619-48620]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-23242]



[[Page 48619]]

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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 96-NM-231-AD; Amendment 39-9755; AD 96-19-08]
RIN 2120-AA64


Airworthiness Directives; Saab Model SAAB 2000 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This amendment adopts a new airworthiness directive (AD) that 
is applicable to certain Saab Model SAAB 2000 series airplanes. This 
action requires repetitive visual inspections to detect whether the de-
icing system boots on the horizontal stabilizer are inflating fully. It 
also requires modification of the stabilizer de-icing system tube as 
terminating action for the repetitive inspections. This amendment is 
prompted by reports indicating that condensational water may collect in 
the de-icing system tube, freeze in low temperatures, and keep the 
boots from inflating fully. The actions specified in this AD are 
intended to prevent such failure which, if not corrected, could keep 
the stabilizer de-icing system from operating properly, and 
consequently result in reduced controllability of the airplane.

DATES: Effective October 1, 1996.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of October 1, 1996.
    Comments for inclusion in the Rules Docket must be received on or 
before November 15, 1996.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 96-NM-231-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056.
    The service information referenced in this AD 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; or at the 
Office of the Federal Register, 800 North Capitol Street, NW., suite 
700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Ruth Harder, Aerospace Engineer, 
Standardization Branch, ANM-113, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (206) 
227-1721; fax (206) 227-1149.

SUPPLEMENTARY INFORMATION: The Luftfartsverket (LFV), which is the 
airworthiness authority for Sweden, recently notified the FAA that an 
unsafe condition may exist on certain Saab Model SAAB 2000 series 
airplanes. The LFV advises that it has received reports indicating that 
the de-icing system boots on the horizontal stabilizer do not always 
inflate fully in low temperatures. Condensational water, which collects 
in the stabilizer de-icing system, can freeze in low temperatures and 
prevent air from moving through the de-icing tube and properly 
inflating the boots. This condition, if not corrected, could result in 
failure of the de-icing system for the horizontal stabilizer, 
consequently leading to reduced controllability of the airplane.
    In addition, the LFV has received reports indicating that the 
Engine Indication and Crew Alerting System (EICAS) displays in the 
cockpit continue to show that the de-icing system is operating properly 
although the stabilizer boots may not be inflating fully; consequently, 
the flightcrew is not aware that this system is not operating properly.

Explanation of Relevant Service Information

    Saab has issued Service Bulletin SAAB 2000-30-006, dated December 
22, 1995, which describes procedures for modifying the de-icing system 
tube. Modification is accomplished by drilling a hole in the tube. The 
LFV classified this service bulletin as mandatory and issued Swedish 
airworthiness directive (SAD) 1-084, dated January 3, 1996, in order to 
assure the continued airworthiness of these airplanes in Sweden.
    In that SAD, the LFV also required repetitive visual inspections of 
the stabilizer de-icing boots prior to modification of the de-icing 
tube, and established conditions for conducting those inspections.

FAA's Conclusions

    This airplane model is manufactured in Sweden 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 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 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, this AD is being issued to prevent condensational 
water from collecting in the tube of the de-icing system on the 
horizontal stabilizer. This AD requires repetitive visual inspections 
of the stabilizer de-icing boots after each flight to determine if they 
are operating fully. This AD also requires the de-icing tube to be 
modified by drilling a hole to allow condensational water to drain; 
such modification constitutes terminating action for the repetitive 
inspections. The modification is required to be accomplished in 
accordance with the service bulletin described previously.

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.

[[Page 48620]]

    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 96-NM-231-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, 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 adding the following new 
airworthiness directive:

96-19-08 Saab Aircraft AB: Amendment 39-9755. Docket 96-NM-231-AD.

    Applicability: Model SAAB 2000 series airplanes having serial 
numbers 004 through 030, certificated in any category.

    Note 1: 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 condensational water from collecting in the tube of 
the de-icing system for the horizontal stabilizer, which could cause 
the system to fail in low temperatures, and consequently lead to 
reduced controllability of the airplane, accomplish the following:
    (a) Within 10 days after the effective date of this AD, conduct 
a visual inspection of the boots of the stabilizer de-icing system 
to determine whether the boots on the horizontal stabilizer are 
inflating fully. This inspection shall be conducted while the 
airplane is parked, using the Auxiliary Power Unit (APU) bleed air 
to operate the stabilizer de-icing system for one cycle, to 
determine whether the boots on the horizontal stabilizer have 
inflated fully.
    (1) If the boots inflate fully, repeat the inspection after each 
flight until the modification required by paragraph (b) of this AD 
has been accomplished.
    (2) If the boots do not inflate fully, prior to further flight, 
perform the modification required by paragraph (b) of this AD.
    (b) Within 30 days after the effective date of this AD, modify 
the tube in the stabilizer de-icing system by drilling a hole, in 
accordance with Saab Service Bulletin SAAB 2000-30-006, dated 
December 22, 1995. This modification constitutes terminating action 
for the visual inspections required by paragraph (a) of this AD.
    (c) As of the effective date of this AD, no person shall install 
on any airplane a de-icing tube having Saab part number (P/N) 
7330100-542 (on Model SAAB 2000 series airplanes having serial 
numbers 004 through 008, inclusive) or P/N 7330101-651 (on Model 
SAAB 2000 series airplanes having serial numbers 009 through 030, 
inclusive) unless that tube has been modified in accordance with 
Saab Service Bulletin SAAB 2000-30-006, dated December 22, 1995, 
prior to installation.
    (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.
    (f) The modification shall be done in accordance with Saab 
Service Bulletin SAAB 2000-30-006, dated December 22, 1995. 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 SAAB Aircraft AB, SAAB Aircraft 
Product Support, S-581.88, Linkoping, Sweden. 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.
    (g) This amendment becomes effective on October 1, 1996.

    Issued in Renton, Washington, on September 5, 1996.
James V. Devany,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 96-23242 Filed 9-13-96; 8:45 am]
BILLING CODE 4910-13-U