[Federal Register Volume 61, Number 175 (Monday, September 9, 1996)]
[Rules and Regulations]
[Pages 47410-47411]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-22600]


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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 95-NM-264-AD; Amendment 39-9746; AD 96-18-19]
RIN 2120-AA64


Airworthiness Directives; de Havilland Model DHC-7 Series 
Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to certain de Havilland Model DHC-7 series airplanes, that 
requires repetitive non-destructive inspections to detect disbonding of 
fuselage skin panels, and repair, if necessary. This amendment is 
prompted by a report of disbonding on fuselage skin panels, which was 
attributed to a manufacturing process error. The actions specified by 
this AD are intended to prevent disbonding of the skin panels of the 
fuselage, which could result in degradation of the structural 
capability of the airplane fuselage.

DATES: Effective October 15, 1996.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of October 15, 1996.

ADDRESSES: The service information referenced in this AD may be 
obtained from Bombardier, Inc., Bombardier Regional Aircraft Division, 
Garratt Boulevard, Downsview, Ontario, Canada M3K 1Y5. This information 
may be examined at the Federal Aviation Administration (FAA), Transport 
Airplane Directorate, Rules Docket, 1601 Lind Avenue, SW., Renton, 
Washington; or at the FAA, New York Aircraft Certification Office, 
Engine and Propeller Directorate, 10 Fifth Street, Third Floor, Valley 
Stream, New York; or at the Office of the Federal Register, 800 North 
Capitol Street, NW., suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Sol Maroof, Aerospace Engineer, 
Airframe and Propulsion Branch, ANE-171, FAA, New York Aircraft 
Certification Office, Engine and Propeller Directorate, 10 Fifth 
Street, Third Floor, Valley Stream, New York 11581; telephone (516) 
256-7522; fax (516) 568-2716.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) to include an airworthiness 
directive (AD) that is applicable to certain de Havilland Model DHC-7 
series airplanes was published in the Federal Register on May 21, 1996 
(61 FR 25417). That action proposed to require repetitive non-
destructive inspections to detect disbonding of the fuselage skin 
panels, and repair, if necessary.
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the single comment received.
    The commenter supports the proposed rule.

Conclusion

    After careful review of the available data, including the comment 
noted above, the FAA has determined that air safety and the public 
interest require the adoption of the rule as proposed.

Cost Impact

    The FAA estimates that 50 de Havilland Model DHC-7 series airplanes 
of U.S. registry will be affected by this AD, that it will take 
approximately 18 work hours per airplane to accomplish the required 
actions, and that the average labor rate is $60 per work hour. Based on 
these figures, the cost impact of the AD on U.S. operators is estimated 
to be $54,000, or $1,080 per airplane, per inspection cycle.
    The cost impact figure discussed above is based on assumptions that 
no operator has yet accomplished any of the 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 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.
    For the reasons discussed above, I certify that this action (1) is 
not a ``significant regulatory action'' under

[[Page 47411]]

Executive Order 12866; (2) is not a ``significant rule'' under DOT 
Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); 
and (3) 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 final evaluation has been prepared 
for this action and it is contained in the Rules Docket. A copy of it 
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:

96-18-19 De Havilland, Inc.: Amendment 39-9746. Docket 95-NM-264-AD.

    Applicability: Model DHC-7 series airplanes, serial numbers 003 
through 113 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 request approval for an 
alternative method of compliance in accordance with paragraph (b) 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 disbonding of the skin panels of the fuselage, which 
could result in degradation of the structural capability of the 
airplane fuselage, accomplish the following:
    (a) Within 6 months after the effective date of this AD, perform 
a non-destructive inspection to detect disbonding of the fuselage 
skin panels, in accordance with the Accomplishment Instructions of 
Bombardier Service Bulletin S.B. 7-51-1, Revision 'A', dated March 
31, 1995.
    (1) If no disbonding is detected, repeat the inspection 
thereafter at intervals not to exceed 3 years.
    (2) If any disbonding is detected, prior to further flight, 
repair it in accordance with a method approved by the Manager, New 
York Aircraft Certification Office (ACO), FAA, Engine and Propeller 
Directorate.
    (b) 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 New York Aircraft Certification Office 
(ACO), FAA, Engine and Propeller Directorate. Operators shall submit 
their requests through an appropriate FAA Principal Maintenance 
Inspector, who may add comments and then send it to the Manager, New 
York ACO.

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the New York ACO.

    (c) 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.
    (d) The inspections shall be done in accordance with Bombardier 
Service Bulletin S.B. 7-51-1, Revision 'A', dated March 31, 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 Bombardier, Inc., Bombardier 
Regional Aircraft Division, Garratt Boulevard, Downsview, Ontario, 
Canada M3K 1Y5. Copies may be inspected at the FAA, Transport 
Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or 
at the FAA, New York Aircraft Certification Office, Engine and 
Propeller Directorate, 10 Fifth Street, Third Floor, Valley Stream, 
New York; or at the Office of the Federal Register, 800 North 
Capitol Street, NW., suite 700, Washington, DC.
    (e) This amendment becomes effective on October 15, 1996.

    Issued in Renton, Washington, on August 29, 1996.
Bill R. Boxwell,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 96-22600 Filed 9-4-96; 8:45 am]
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