[Federal Register Volume 64, Number 78 (Friday, April 23, 1999)]
[Proposed Rules]
[Pages 19932-19934]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-10172]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-CE-05-AD]
RIN 2120-AA64


Airworthiness Directives; deHavilland Inc. Models DHC-2 Mk. I, 
DHC-2 Mk. II, and DHC-2 Mk. III Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes to adopt a new airworthiness directive 
(AD) that would apply to all deHavilland Inc. (deHavilland) Models DHC-
2 Mk. I, DHC-2 Mk. II, and DHC-2 Mk. III airplanes. The proposed AD 
would require repetitively inspecting the rear fuselage bulkhead at 
Station 228 for cracks. The proposed AD would also require repairing 
any crack found or replacing any cracked rear fuselage bulkhead in 
accordance with a repair or replacement scheme obtained from the 
manufacturer through the Federal Aviation Administration (FAA). The 
proposed AD is the result of mandatory continuing airworthiness 
information (MCAI) issued by the airworthiness authority for Canada. 
The actions specified by the proposed AD are intended to detect and 
correct cracking of the rear fuselage bulkhead at Station 228, which 
could result in structural damage of the fuselage to the point of 
failure with consequent loss of airplane control.

DATES: Comments must be received on or before May 21, 1999.

ADDRESSES: Submit comments in triplicate to the FAA, Central Region, 
Office of the Regional Counsel, Attention: Rules Docket No. 99-CE-05-
AD, Room 1558, 601 E. 12th Street, Kansas City, Missouri 64106. 
Comments may be inspected at this location between 8 a.m. and 4 p.m., 
Monday through Friday, holidays excepted. Service information that 
applies to the proposed AD may be obtained from Bombardier Inc., 
Bombardier Regional Aircraft Division, Garratt Boulevard, Downsview, 
Ontario, Canada M3K 1Y5; telephone: (416) 633-7310. This information 
also may be examined at the Rules Docket at the address above.

FOR FURTHER INFORMATION CONTACT: Mr. James Delisio, Aerospace Engineer, 
FAA, New York Aircraft Certification Office, 10 Fifth Street, 3rd 
Floor, Valley Stream, New York 11581-1200; telephone: (516) 256-7521; 
facsimile: (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 should 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 that summarizes 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 No. 99-CE-05-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, Central Region, Office of the Regional Counsel, Attention: 
Rules Docket No. 99-CE-05-AD, Room 1558, 601 E. 12th Street, Kansas 
City, Missouri 64106.

Discussion

    Transport Canada, which is the airworthiness authority for Canada, 
recently notified the FAA that an unsafe condition may exist on all 
deHavilland Models DHC-2 Mk. I, DHC-2 Mk. II, and DHC-2 Mk. III 
airplanes. Transport Canada reports three incidents of cracks found in 
the rear fuselage bulkhead at Station 228. The airplanes involved in 
these incidents had between 10,000 and 12,000 hours time-in-service 
(TIS).
    This condition, if not detected and corrected in a timely manner, 
could result in structural damage of the fuselage to the point of 
failure with consequent loss of airplane control.

[[Page 19933]]

Relevant Service Information

    Bombardier Inc. has issued the following service information to 
address the above-referenced condition:

--deHavilland Beaver Service Bulletin 2/52, dated August 30, 1998, 
which specifies procedures for inspecting the rear fuselage bulkhead at 
Station 228 for cracks on Models DHC-2 Mk. I and DHC-2 Mk. II 
airplanes; and
--deHavilland Beaver Service Bulletin TB/60, dated August 30, 1998, 
which specifies procedures for inspecting the rear fuselage bulkhead at 
Station 228 for cracks on Model DHC-2 Mk. III airplanes.

    Transport Canada classified these service bulletins as mandatory 
and issued Canadian AD No. CF-98-38, dated October 15, 1998, in order 
to assure the continued airworthiness of these airplanes in Canada.

The FAA's Determination

    This airplane model is manufactured in Canada 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, Transport Canada has kept the FAA 
informed of the situation described above.
    The FAA has examined the findings of Transport Canada; reviewed all 
available information, including the service information referenced 
above; and determined that AD action is necessary for products of this 
type design that are certificated for operation in the United States.

Explanation of the Provisions of the Proposed AD

    Since an unsafe condition has been identified that is likely to 
exist or develop in other deHavilland Models DHC-2 Mk. I, DHC-2 Mk. II, 
and DHC-2 Mk. III airplanes of the same type design registered in the 
United States, the FAA is proposing AD action. The proposed AD would 
require the following:

--Repetitively inspecting the rear fuselage bulkhead at Station 228 for 
cracks in accordance with the previously referenced service 
information; and
--Repairing any crack found or replacing any cracked rear fuselage 
bulkhead in accordance with a repair or replacement scheme obtained 
from the manufacturer through the FAA.

Compliance Time of the Proposed AD

    The compliance time of the proposed AD is presented in both 
calendar time and hours TIS. While cracks are generally a result of 
classic fatigue (i.e., aging and cylic operation), the FAA and 
Bombardier believe that the condition could develop over time 
regardless of how often the airplane is operated. In order to assure 
that rear fuselage bulkhead cracking does not go undetected, a 
compliance time of specific hours TIS and calendar time (whichever 
occurs first) is proposed.

Cost Impact

    The FAA estimates that 350 airplanes in the U.S. registry would be 
affected by the proposed AD, that it would take approximately 1 
workhour per airplane to accomplish the proposed initial inspection, 
and that the average labor rate is approximately $60 an hour. Based on 
these figures, the total cost impact of the proposed initial inspection 
on U.S. operators is estimated to be $21,000, or $60 per airplane. 
These figures only take into the account the costs of the initial 
inspection and do not take into account the costs of the repetitive 
inspections or the cost of any repair or replacement necessary if any 
rear fuselage bulkhead was found cracked. The FAA has no way of 
determining the number of repetitive inspections each owner/operator 
would incur over the life of his/her affected airplane or the number of 
airplanes that would have a cracked rear fuselage bulkhead and need 
repair or replacement.

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 action (1) is 
not a ``significant regulatory action'' under Executive Order 12866; 
(2) is not a ``significant rule'' under 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 has been placed 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 a new airworthiness directive 
(AD) to read as follows:

deHavilland Inc. Docket No. 99-CE-05-AD.

    Applicability: Models DHC-2 Mk. I, DHC-2 Mk. II, and DHC-2 Mk. 
III airplanes, all serial numbers, 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 (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 in the body of this AD, unless 
already accomplished.
    To detect and correct cracking of the rear fuselage bulkhead at 
Station 228, which could result in structural damage of the fuselage 
to the point of failure with consequent loss of airplane control, 
accomplish the following:
    (a) Within the next 400 hours time-in-service (TIS) after the 
effective date of this AD or within the next 12 calendar months 
after the effective date of this AD, whichever occurs first, and 
thereafter at intervals not to exceed 2,000 hours TIS or 5 years, 
whichever occurs first, inspect the rear fuselage bulkhead at 
Station 228 for cracks. Inspect in accordance with the 
Accomplishment Instructions section of whichever of the following 
service bulletins that is applicable:
    (1) For the Models DHC-2 Mk. I and DHC-2 Mk. II airplanes: 
deHavilland Beaver

[[Page 19934]]

Service Bulletin 2/52, dated August 30, 1998; or
    (2) For the Model DHC-2 Mk. III airplanes: deHavilland Beaver 
Service Bulletin TB/60, dated August 30, 1998.
    (b) If any crack(s) is/are found in the rear fuselage bulkhead 
at Station 228 during any inspection required by paragraph (a) of 
this AD, prior to further flight, accomplish the following:
    (1) Obtain a repair or replacement scheme from the manufacturer 
through the FAA, New York Aircraft Certification Office (ACO), 10 
Fifth Street, 3rd Floor, Valley Stream, New York 11581-1200; 
facsimile: (516) 568-2716.
    (2) Incorporate this repair or replacement scheme.
    (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) An alternative method of compliance or adjustment of the 
initial or repetitive compliance times that provides an equivalent 
level of safety may be approved by the Manager, New York Aircraft 
ACO, 10 Fifth Street, 3rd Floor, Valley Stream, New York 11581-1200. 
The request shall be forwarded through an appropriate FAA 
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.

    (e) Questions or technical information related to deHavilland 
Beaver Service Bulletin TB/60, dated August 30, 1998, and 
deHavilland Beaver Service Bulletin 2/52, dated August 30, 1998, 
should be directed to Bombardier Inc., Bombardier Regional Aircraft 
Division, Garratt Boulevard, Downsview, Ontario, Canada M3K 1Y5; 
telephone: (416) 633-7310. This service information may be examined 
at the FAA, Central Region, Office of the Regional Counsel, Room 
1558, 601 E. 12th Street, Kansas City, Missouri 64106.

    Note 3: The subject of this AD is addressed in Canadian AD No. 
CF-98-38, dated October 15, 1998.

    Issued in Kansas City, Missouri, on April 15, 1999.
Michael Gallagher,
Manager, Small Airplane Directorate, Aircraft Certification Service.
[FR Doc. 99-10172 Filed 4-22-99; 8:45 am]
BILLING CODE 4910-13-P