[Federal Register Volume 65, Number 63 (Friday, March 31, 2000)]
[Proposed Rules]
[Pages 17206-17208]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-8020]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-NM-380-AD]
RIN 2120-AA64


Airworthiness Directives; Bombardier Model DHC-8-100 and -300 
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 certain Bombardier Model DHC-8-100 
and -300 series airplanes. This proposal would require revising the 
Aircraft Log Book to correct the airplane Production Modification List; 
performing an inspection to determine which bonded skin panels on the 
airplane require bonding integrity inspections (BII); and revising the 
Airworthiness Limitations List of the Approved Maintenance Plan to 
include the BII requirements. This proposal also would, for certain 
airplanes, require repetitive ultrasonic bond inspections to detect 
disbonding of airplane skin panels, and repair, if necessary. This 
proposal is prompted by issuance of mandatory continuing airworthiness 
information by a foreign civil airworthiness authority. The actions 
specified by the proposed AD are intended to prevent damage to bonded 
skin panels to go undetected, which could result in failure of the 
bonded skin panels, and consequent loss of controllability of the 
airplane.

DATES: Comments must be received by May 1, 2000.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 98-NM-

[[Page 17207]]

380-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 Bombardier, Inc., Bombardier Regional Aircraft Division, 
Garratt Boulevard, Downsview, Ontario M3K 1Y5, Canada. This information 
may be examined at the FAA, Transport Airplane Directorate, 1601 Lind 
Avenue, SW., Renton, Washington; or at the FAA, Engine and Propeller 
Directorate, New York Aircraft Certification Office, 10 Fifth Street, 
Third Floor, Valley Stream, New York.

FOR FURTHER INFORMATION CONTACT: Franco Pieri, Aerospace Engineer, 
Airframe and Propulsion Branch, ANE-171, FAA, Engine and Propeller 
Directorate, New York Aircraft Certification Office, 10 Fifth Street, 
Third Floor, Valley Stream, New York 11581; telephone (516) 256-7526; 
fax (516) 568-2716.

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 98-NM-380-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. 98-NM-380-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    Transport Canada Civil Aviation (TCCA), which is the airworthiness 
authority for Canada, notified the FAA that an unsafe condition may 
exist on certain Bombardier Model DHC-8-100 and -300 series airplanes. 
TCCA advises that, during a Bombardier investigation of an operator 
query, inconsistencies were found between the effectivity tables for 
the bonding integrity inspection (BII) in the non-destructive testing 
manuals and the modification status record in the airplane Modification 
Log. As a result of these inconsistencies, some of the bonded skin 
panels on affected DHC-8 aircraft were not being inspected under the 
BII program even though they were manufactured with panels that require 
a bonding integrity inspection. Failure to conduct these inspections 
could allow damage to bonded skin panels to go undetected, which could 
result in failure of the bonded skin panels, and consequent loss of 
controllability of the airplane.

Explanation of Relevant Service Information

    Bombardier has issued Service Bulletin S.B. 8-51-2, Revision `A,' 
dated September 19, 1998, which describes procedures for revising the 
Aircraft Log Book to correct the airplane Production Modification List; 
performing an inspection to determine which bonded skin panels on the 
airplane require the BII program; and revising the Airworthiness 
Limitations List of the Approved Maintenance Plan to include the BII 
requirements.
    Bombardier also has issued Part 5, sections 55-00-01 and 57-30-01 
of Bombardier Production Support Manual (PSM) 1-8-7A, dated December 
15, 1998 (for Model DHC-8-100 series airplanes); and Part 5, sections 
55-00-01 and 57-30-01 of Bombardier PSM 1-83-7A, dated April 30, 1999 
(for Model DHC-8-300 series airplanes) which describe procedures for 
repetitive ultrasonic bond inspections to detect disbonding of the 
affected airplane skin panels and repair, if necessary.
    Accomplishment of the actions specified in the service bulletin and 
service information is intended to adequately address the identified 
unsafe condition. TCCA classified this service bulletin and service 
information as mandatory and issued Canadian airworthiness directive 
CF-98-31, dated September 1, 1998, in order to assure the continued 
airworthiness of these airplanes in Canada.

FAA's Conclusions

    These airplane models are manufactured in Canada and are 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, TCCA has kept the FAA informed of 
the situation described above. The FAA has examined the findings of 
TCCA, 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 information described previously, 
except as discussed below.

Differences Between Proposed Rule and Service Information

    Operators should note that, although the service information 
specifies that the manufacturer may be contacted for disposition of 
certain repair conditions, this proposal would require the repair of 
those conditions to be accomplished in accordance with a method 
approved by the FAA.
    Operators also should note that, although the Canadian 
airworthiness directive affects Bombardier Model DHC-8-314 series 
airplanes, Bombardier Model DHC-8-314 series airplanes are not type 
certificated in the United States. Therefore, the proposed AD does not 
affect those airplanes.

Cost Impact

    The FAA estimates that 41 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 revisions to the Aircraft 
Log Book, Approved Maintenance Plan, and inspection, and that the 
average labor rate is $60 per work hour. Based on these figures, the 
cost impact of the actions proposed by this AD on U.S. operators is 
estimated to be $2,460, or $60 per airplane.

[[Page 17208]]

    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 adding the following new 
airworthiness directive:

Bombardier Inc. (Formerly de Havilland, Inc.): Docket 98-NM-380-AD.

    Applicability: DHC-8-100 and -300 series airplanes, serial 
numbers 215 through 341 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 (e) 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 damage to bonded skin panels to go undetected, which 
could result in failure of the bonded skin panels, and consequent 
loss of controllability of the airplane; accomplish the following:

Revision to Aircraft Log Book and Airworthiness Limitations List

    (a) Within 30 days after the effective date of this AD, perform 
the actions required by paragraphs (a)(1), (a)(2), and (a)(3) of 
this AD.
    (1) Revise the Aircraft Log Book to correct the airplane 
Production Modification List in accordance with the Accomplishment 
Instructions in Part A of Section III of Bombardier Service Bulletin 
S.B. 8-51-2, Revision `A,' dated September 19, 1998.
    (2) Perform an inspection to determine which bonded skin panels 
on the airplane require bonding integrity inspections (BII) in 
accordance with the Accomplishment Instructions in Part B of Section 
III of Bombardier Service Bulletin S.B. 8-51-2, Revision `A,' dated 
September 19, 1998.
    (3) Revise the Airworthiness Limitations List of the Approved 
Maintenance Plan by inserting the bonding integrity inspections 
identified as de Havilland Maintenance Task 5500/01 and de Havilland 
Maintenance Task 5700/01 into the Airworthiness Limitations List. 
Except as provided by paragraph (e) of this AD: After the actions 
specified in paragraph (a)(3) of this AD have been accomplished, no 
alternative replacement times or structural inspection intervals may 
be approved for the bonded panels of the empennage and wings 
specified in de Havilland Maintenance Task 5500/01 and de Havilland 
Maintenance Task 5700/01.

On-Condition Repetitive Inspections

    (b) For airplanes on which the bonded skin panels require BII's, 
as determined in paragraph (a)(2) of this AD: At the next required 
maintenance visit, but no later than 12 months after the effective 
date of this AD, perform an initial ultrasonic bond inspection to 
detect disbonding of the skin panels, in accordance with Part 5, 
sections 55-00-01 and/or 57-30-01, of Bombardier Production Support 
Manual (PSM) 1-8-7A, dated December 15, 1998 (for Model DHC-8-100 
series airplanes); or Part 5, sections 55-00-01 and 57-30-01 of 
Bombardier PSM 1-83-7A, dated April 30, 1999 (for Model DHC-8-300 
series airplanes); as applicable. Thereafter, repeat the ultrasonic 
inspection at the interval specified in the applicable PSM.

On-Condition Repair

    (c) Except as provided by paragraph (d) of this AD, if any 
disbonding is detected during any inspection required by paragraph 
(b) of this AD, prior to further flight, repair in accordance with 
Part 5, sections 55-00-01 and 57-30-01 of Bombardier PSM 1-8-7A, 
dated December 15, 1998 (for Model DHC-8-100 series airplanes); or 
Part 5, sections 55-00-01 and 57-30-01 of Bombardier PSM 1-83-7A, 
dated April 30, 1999 (for Model DHC-8-300 series airplanes); as 
applicable.
    (d) If any disbonding is detected during any inspection required 
by paragraph (b) of this AD; and the applicable service information 
specifies to contact Bombardier for appropriate action: Prior to 
further flight, repair in accordance with a method approved by the 
Manager, New York Aircraft Certification Office (ACO), FAA, Engine 
and Propeller Directorate. For a repair method to be approved by the 
Manager, New York ACO, as required by this paragraph, the Manager's 
approval letter must specifically reference this AD.

Alternative Methods of Compliance

    (e) 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, New York ACO. 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.

Special Flight Permits

    (f) Special flight permits may be issued in accordance with 
Secs. 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 Canadian 
airworthiness directive.


    Issued in Renton, Washington, on March 27, 2000.
Donald L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 00-8020 Filed 3-30-00; 8:45 am]
BILLING CODE 4910-13-P