[Federal Register Volume 67, Number 60 (Thursday, March 28, 2002)]
[Proposed Rules]
[Pages 14886-14889]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 02-7417]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-CE-124-AD]
RIN 2120-AA64


Airworthiness Directives; de Havilland 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 certain de Havilland Inc. (de Havilland) 
Models DHC-2 Mk. I, DHC-2 Mk. II, and DHC-2 Mk. III airplanes. This 
proposed AD would establish a life limit for the front fuselage struts 
and would require you to repetitively replace the front fuselage struts 
every 15 years or repetitively inspect the struts for corrosion or 
fatigue damage and replace when the damage exceeds a certain level. 
This 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 prevent 
structural failure of the front fuselage caused by corrosion or fatigue 
damage to the struts that develops over time, which could result in 
reduced or loss of control of the airplane.

DATES: The Federal Aviation Administration (FAA) must receive any 
comments on this proposed rule on or before May 10, 2002.

ADDRESSES: Submit comments to FAA, Central Region, Office of the 
Regional Counsel, Attention: Rules Docket No. 98-CE-124-AD, 901 Locust, 
Room 506, Kansas City, Missouri 64106. You may view any comments at 
this location between 8 a.m. and 4 p.m., Monday through Friday, except 
Federal holidays. You may also send comments electronically to the 
following address: [email protected]. Comments sent electronically 
must contain ``Docket No. 98-CE-124-AD'' in the subject line. If you 
send comments electronically as attached electronic files, the files 
must be formatted in Microsoft Word 97 for Windows or ASCII text.
    You may get service information that applies to this proposed AD 
from Bombardier Inc., Bombardier Regional Aircraft Division, 123 
Garratt Boulevard, Downsview, Ontario, Canada M3K 1Y5; telephone: (416) 
633-7310. You may also view this information at the Rules Docket at the 
address above.

FOR FURTHER INFORMATION CONTACT: Mr. Jon Hjelm, Aerospace Engineer, New 
York Aircraft Certification Office, 10 Fifth Street, 3rd Floor, Valley 
Stream, New York 11581-1200; telephone: (516) 256-7523; facsimile: 
(516) 568-2716.

SUPPLEMENTARY INFORMATION:   

Comments Invited

How do I Comment on This Proposed AD?

    The FAA invites comments on this proposed rule. You may submit 
whatever written data, views, or arguments you choose. You need to 
include the rule's docket number and submit your comments to the 
address specified under the caption ADDRESSES. We will consider all 
comments received on or before the closing date. We may amend this 
proposed rule in light of comments received. Factual information that 
supports your ideas and suggestions is extremely helpful in evaluating 
the effectiveness of this proposed AD action and determining whether we 
need to take additional rulemaking action.

Are There any Specific Portions of This Proposed AD I Should Pay 
Attention to?

    The FAA specifically invites comments on the overall regulatory, 
economic, environmental, and energy aspects of this proposed rule that 
might suggest a need to modify the rule. You may view all comments we 
receive before and after the closing date of the rule in the Rules 
Docket. We will file a report in the Rules Docket that summarizes each 
contact we have with the public that concerns the substantive parts of 
this proposed AD.

How can I be Sure FAA Receives my Comment?

    If you want FAA to acknowledge the receipt of your mailed comments, 
you must include a self-addressed, stamped postcard. On the postcard, 
write ``Comments to Docket No. 98-CE-124-AD.'' We will date stamp and 
mail the postcard back to you.

Discussion

What Events Have Caused This Proposed AD?

    Transport Canada, which is the airworthiness authority for Canada, 
notified FAA that an unsafe condition may exist on certain de Havilland 
Models DHC-2 Mk. I, DHC-2 Mk. II, and DHC-2 Mk. III airplanes. 
Transport Canada reports numerous incidents of corrosion of the front 
fuselage struts. Further analysis of the front fuselage struts reveals 
that these parts are not life limited and incur corrosion and fatigue 
damage over time.

What are the Consequences if the Condition is not Corrected?

    Corrosion damage, if not detected and corrected, could result in 
failure of the front fuselage and possible reduced or loss of control 
of the airplane.

Is There Service Information That Applies to This Subject?

    De Havilland Inc. has issued Parts Service Manual (PSM) No. 1-2-2, 
Part 5, Temporary Revision 2-22; and PSM No. 1-2T-2, Part 5, Temporary 
Revision 2T-6, both dated August 3, 1998. These service documents 
establish a life limit of 15 years for the front fuselage struts. The 
procedures for replacement of the front fuselage struts are included in 
the applicable maintenance manual.

[[Page 14887]]

What Action did the Transport Canada Take?

    Transport Canada issued Canadian AD CF-98-37, dated September 29, 
1998, in order to ensure the continued airworthiness of these airplanes 
in Canada. This Canadian AD established a 15-year life limit on the 
front fuselage struts and requires replacement at that time on the 
affected airplanes in the Canadian registry.
    Transport Canada revised this AD (Canadian AD CF-98-37R1, dated 
August 20, 1999) to allow repetitive inspections of the front fuselage 
struts until corrosion damage exceeds a certain limit. When it exceeds 
this limit, front fuselage strut replacement is mandatory.

Was This in accordance With the Bilateral Airworthiness Agreement?

    These airplane models are manufactured in Canada 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, Transport 
Canada has kept FAA informed of the situation described above.

The FAA's Determination and an Explanation of the Provisions of 
this Proposed AD

What has FAA Decided?

    The FAA has examined the findings of Transport Canada; reviewed all 
available information, including the service information referenced 
above; and determined that:
--The unsafe condition referenced in this document exists or could 
develop on de Havilland Inc. Models DHC-2 Mk. I, DHC-2 Mk. II, and DHC-
2 Mk. III airplanes of the same type design that are on the U.S. 
registry;
--A life limit of 15 years should be established on the front fuselage 
struts of the affected airplanes; and
--AD action should be taken in order to correct this unsafe condition.

What Would This Proposed AD Require?

    This proposed AD would establish a life limit for the front 
fuselage struts and would require you to repetitively replace the front 
fuselage struts every 15 years or repetitively inspect the struts for 
corrosion or fatigue damage and replace when the damage exceeds a 
certain level.

Cost Impact

How Many Airplanes Would This Proposed AD Impact?

    We estimate that this proposed AD would affect 354 airplanes in the 
U.S. registry.

What Would be the Cost Impact of This Proposed AD on Owners/Operators 
of the Affected Airplanes?

    We estimate the following costs to accomplish each proposed 
replacement:

--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                          Parts cost   Total cost
                       Labor cost                            per          per                           Total cost on U.S. operators
                                                           airplane     airplane
--------------------------------------------------------------------------------------------------------------------------------------------------------
108 workhours X $60 an hour = $6,480 per airplane......       $2,352       $8,832                                            $3,126,528 per replacement
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Compliance Time of this Proposed AD

What Would be the Compliance Time of This Proposed AD?

    The replacement compliance time of this proposed AD is upon 
accumulating 15 years from the date of installation of the front 
fuselage struts or within the next 12 calendar months after the 
effective date of this AD, whichever occurs later, and thereafter at 
intervals not to exceed 15 years. If the repetitive inspection option 
is used, then the repetitive compliance time interval would be at 1 and 
5 years depending on the method used (provided certain corrosion or 
damage limits are not exceeded).

Why is the Compliance Time Presented in Calendar Time Instead of Hours 
Time-in-Service (TIS)?

    The compliance of the proposed AD is presented in calendar time 
instead of hours TIS. The need for establishing a life limit for the 
front fuselage struts as specified in the proposed AD is the result of 
reports of corrosion found in this area on the affected airplanes. 
Corrosion can occur regardless of whether the aircraft is in operation. 
In order to ensure that the unsafe condition specified in the proposed 
AD does not go undetected if the airplane was not in operation for an 
extended period of time, the compliance is presented in calendar time 
instead of hours TIS.

Regulatory Flexibility Determination and Analysis

What are the requirements of the Regulatory Flexibility Act?

    The Regulatory Flexibility Act of 1980 was enacted by Congress to 
assure that small entities are not unnecessarily or disproportionately 
burdened by government regulations. This Act establishes ``as principle 
of regulatory issuance that agencies shall endeavor, consistent with 
the objectives of the rule and of applicable statutes, to fit 
regulatory and informational requirements to the scale of the 
businesses, organizations, and governmental jurisdictions subject to 
regulation.'' To achieve this principle, the Act requires agencies to 
solicit and consider flexible regulatory proposals and to explain the 
rationale for their actions. The Act covers a wide range of small 
entities, including small businesses, not-for-profit organizations, and 
small governmental jurisdictions.
    Agencies must perform a review to determine whether a proposed or 
final rule will have a significant economic impact on a substantial 
number of small entities. If the determination is that the rule will, 
the Agency must prepare a regulatory flexibility analysis as described 
in the RFA.
    However, if an agency determines that a proposed or final rule is 
not expected to have a significant economic impact on a substantial 
number of small entities, section 605(b) of the RFA provides that the 
head of the agency may so certify and a regulatory flexibility analysis 
is not required. The certification must include a statement providing 
the factual basis for this determination, and the reasoning should be 
clear.

What is FAA's Determination?

    The FAA has determined that this proposed AD could have a 
significant economic impact on a substantial number of small entities. 
However, we have determined that we should continue with this proposed 
action in order to address the unsafe condition and ensure aviation 
safety.
    You may obtain a copy of the complete Regulatory Flexibility 
Analysis (entitled ``Initial Regulatory Flexibility Analysis'') that 
was prepared for this proposed AD from the Docket file at the location 
listed under the ADDRESSES section of this document.

[[Page 14888]]

Regulatory Impact

Would This Proposed AD Impact Various Entities?

    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 proposed rule would not have federalism 
implications under Executive Order 13132.

Would This Proposed AD Involve a Significant Rule or Regulatory Action?

    For the reasons discussed above, I certify that this proposed 
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, could 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, under 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. FAA amends Sec. 39.13 by adding a new airworthiness directive 
(AD) to read as follows:

de Havilland Inc.: Docket No. 98-CE-124-AD
    (a) What airplanes are affected by this AD? This AD affects all 
serial numbers of Models DHC-2 Mk. I, DHC-2 Mk. II, and DHC-2 Mk. 
III airplanes that are certificated in any category.
    (b) Who must comply with this AD? Anyone who wishes to operate 
any of the airplanes identified in paragraph (a) of this AD must 
comply with this AD.
    (c) What problem does this AD address? The actions specified by 
this AD are intended to prevent structural failure of the front 
fuselage caused by corrosion or fatigue damage to the struts that 
develops over time, which could result in reduced or loss of control 
of the airplane.
    (d) What actions must I accomplish to address this problem? To 
address this problem, you must accomplish the following:

------------------------------------------------------------------------
           Actions                 Compliance            Procedures
------------------------------------------------------------------------
(1) Replace each front        Initially replace     In accordance with
 fuselage strut with a new     upon accumulating     the applicable
 strut. Part numbers for       15 years on each      maintenance manual,
 existing and replacement      front fuselage        as specified in de
 front fuselage struts parts   strut or within the   Havilland Parts
 are presented in paragraph    next 12 calendar      Service Manual 1-2-
 (e) of this AD.               months after the      2, Part 5,
                               effective date of     Temporary Revision
                               this AD, whichever    2-22; and de
                               occurs later.         Havilland Parts
                               Repetitively          Service Manual 1-2T-
                               replace thereafter    2, Part 5,
                               upon accumulating     Temporary Revision
                               15 years on each      2T-6, both dated
                               front fuselage        August 3, 1998.
                               strut.
(2) As an alternative method  Initially inspect     For the detailed
 of compliance to the          upon accumulating     inspection, use an
 replacements in paragraph     15 years on each      inspection light,
 (d)(1) of this AD, you may    front fuselage        inspection mirror,
 repetitively inspect each     strut or within the   and 10X magnifying
 front fuselage strut, as      next 12 calendar      glass. For the
 follows:                      months after the      ultrasonic
                               effective date of     inspection, use FAA-
                               this AD, whichever    approved procedures
                               occurs later.         that follow a
                               Accomplish the        similar calibration
                               repetitive detailed   and measures strut
                               inspection            thickness to that
                               thereafter at         detailed in
                               intervals not to      Bombardier Service
                               exceed 12 months      Bulletin 2/49,
                               and the ultrasonic    Revision C.
                               thickness
                               measurement at
                               intervals not to
                               exceed 5 years.
                               Accomplish the
                               corrosion
                               prevention work
                               prior to further
                               flight after each
                               inspection.
                               Accomplish the
                               replacement prior
                               to further flight
                               after damage is
                               found or the
                               thickness is found
                               below 0.030 inches.
                               Then after
                               replacement either
                               replace with a new
                               strut at 15-year
                               intervals
                               thereafter or
                               repetitively
                               inspect as
                               prescribed above
                               beginning at 15
                               years after each
                               replacement.
(i) perform a detailed
 inspection of each front
 fuselage strut and all
 fittings attached to the
 frame for damage
 (corrosion, cracks, dents).
 When fatigue damage is
 found, you must replace the
 damaged strut. After each
 inspection, clean the drain
 holes around the bottom end
 fitting and protect the
 tube with an appropriate
 corrosion preventive spray.
 Part numbers for existing
 and replacement front
 fuselage struts parts are
 presented in paragraph (e)
 of this AD.
(ii) perform an ultrasonic
 thickness measurement of
 all surfaces on each front
 months and the Service
 fuselage strut. When
 minimum thickness is below
 0.030 inches, you must
 replace the affected strut.
 Part numbers for existing
 and replacement front
 fuselage struts parts are
 presented in paragraph (e)
 of this AD.

[[Page 14889]]

 
(3) Do not install, on any    As of the effective   Not Applicable.
 affected airplane, any        date of this AD.
 front fuselage strut unless
 it has a part number
 specified in the
 Replacement Part Number
 column of the chart
 presented in paragraph (e)
 of this AD.
------------------------------------------------------------------------

    (e) What part number front fuselage struts should I use for 
replacements? The following charts presents the part numbers for 
existing parts and replacement parts for the front fuselage strut 
replacements:

----------------------------------------------------------------------------------------------------------------
                                                Replacement part
            Installed part number                    number                         Description
----------------------------------------------------------------------------------------------------------------
C2FS209 or C2FS3281A.........................          C2FS3281A           Strut Assembly Front Fuselage, Left.
C2FS210 or C2FS3282A.........................          C2FS3282A          Strut Assembly Front Fuselage, Right.
----------------------------------------------------------------------------------------------------------------

    (f) Can I comply with this AD in any other way? You may use an 
alternative method of compliance or adjust the compliance time if:
    (1) Your alternative method of compliance provides an equivalent 
level of safety; and
    (2) The Manager, New York Aircraft Certification Office, 
approves your alternative. Submit your request through an FAA 
Principal Maintenance Inspector, who may add comments and then send 
it to the Manager, New York Aircraft Certification Office.

    Note 1: This AD applies to each airplane identified in paragraph 
(a) of this AD, 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 (f) 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 you have not eliminated the unsafe condition, specify 
actions you propose to address it.

    (g) Where can I get information about any already-approved 
alternative methods of compliance? Contact Jon Hjelm, Aerospace 
Engineer, FAA, New York Aircraft Certification Office, 10 Fifth 
Street, Third Floor, Valley Stream, New York 11581; telephone: (516) 
256-7523; facsimile: (516) 256-2716.
    (h) What if I need to fly the airplane to another location to 
comply with this AD? The FAA can issue a special flight permit under 
sections 21.197 and 21.199 of the Federal Aviation Regulations (14 
CFR 21.197 and 21.199) to operate your airplane to a location where 
you can accomplish the requirements of this AD.
    (i) How do I get copies of the documents referenced in this AD? 
You may direct technical questions to or get copies of the documents 
referenced in this AD from Bombardier Inc., Bombardier Regional 
Aircraft Division, 123 Garratt Boulevard, Downsview, Ontario, Canada 
M3K 1Y5; telephone: (416) 633-7310. You may view these documents at 
FAA, Central Region, Office of the Regional Counsel, 901 Locust, 
Room 506, Kansas City, Missouri 64106.

    Note 2: The subject of this AD is addressed in Canadian AD CF-
98-37R1, dated August 20, 1999.



    Issued in Kansas City, Missouri, on March 20, 2002.
Dorenda D. Baker,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 02-7417 Filed 3-27-02; 8:45 am]
BILLING CODE 4910-13-U