[Federal Register Volume 61, Number 87 (Friday, May 3, 1996)]
[Rules and Regulations]
[Pages 19807-19808]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-10076]



=======================================================================
-----------------------------------------------------------------------

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 95-CE-47-AD; Amendment 39-9578; AD 96-09-04]
RIN 2120-AA64


Airworthiness Directives; de Havilland Model DHC-3 Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

-----------------------------------------------------------------------

SUMMARY: This amendment supersedes Airworthiness Directive (AD) 90-12-
08, which currently requires the following on de Havilland Model DHC-3 
airplanes: repetitively inspecting (using dye penetrant methods) the 
tailplane main rib forward flanges and the main rib forward lower 
flanges at the tailplane front attachment fitting for cracks and 
repairing any cracked flange. This AD action will retain the repetitive 
inspections currently required by AD 90-12-08, and will allow a certain 
modification as terminating action for these repetitive inspections. 
This action is prompted by the Federal Aviation Administration's 
determination that installing new angles and plates on the tailplane 
root ribs on de Havilland Model DHC-3 airplanes provides an equivalent 
level of safety to the repetitive inspections required by AD 90-12-08. 
The actions specified by this AD are intended to prevent failure of the 
tailplane structure caused by cracked tailplane main rib forward 
flanges or main rib forward lower flanges at the tailplane front 
attachment fitting, which, if not detected and corrected, could result 
in loss of control of the airplane.

DATES: Effective May 17, 1996.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of May 17, 1996.

ADDRESSES: Service information that applies to this AD may be obtained 
from Bombardier Inc., (the parent company of de Havilland) Bombardier 
Regional Aircraft Division, Garrett Boulevard, Downsview, Ontario, 
Canada M3K 1Y5; telephone (416) 633-7310. This information may also be 
examined at the Federal Aviation Administration (FAA), Central Region, 
Office of the Assistant Chief Counsel, Attention: Rules Docket 95-CE-
47-AD, Room 1558, 601 E. 12th Street, Kansas City, Missouri 64106; or 
at the Office of the Federal Register, 800 North Capitol Street, NW., 
suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Mr. Jeff Casale, Aerospace Engineer, 
FAA, New York Aircraft Certification Office, 10 5th St., 3rd Floor, 
Valley Stream, New York 11581; telephone (516) 256-7521; facsimile 
(516) 568-2716.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) to include an AD that would apply 
to de Havilland Model DHC-3 airplanes was published in the Federal 
Register on November 14, 1995 (60 FR 57201). This action would retain 
the repetitive inspections currently required by AD 90-12-08, and would 
allow incorporating a certain modification as terminating action for 
these repetitive inspections. Accomplishment of this action will be in 
accordance with de Havilland Service Bulletin (SB) No. 3/46, Revision 
B, dated December 1, 1989 and de Havilland SB No. 3/50, Revision A, 
dated February 17, 1995.
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. No comments were received on the 
proposed rule or the FAA's determination of the cost to the public.
    After careful review of all available information related to the 
subject presented above, the FAA has determined that air safety and the 
public interest require the adoption of the rule as proposed except for 
minor editorial corrections. The FAA has determined that these minor 
corrections will not change the meaning of the AD and will not add any 
additional burden upon the public than was already proposed.
    The FAA estimates that 49 airplanes in the U.S. registry will be 
affected by this AD, that it will take approximately 35 workhours per 
airplane to accomplish the inspection and that the average labor rate 
is approximately $60 an hour. Based on these figures, the total cost 
impact of this AD on U.S. operators is estimated to be $102,900 or 
$2,100 per airplane. This figure represents the cost of the initial 
inspection, and does not reflect the costs for repetitive inspections 
or possible repairs. The FAA has no way of determining how many 
tailplane main rib forward or main rib forward lower flanges may need 
to be repaired or how many repetitive inspections each owner/operator 
of the affected airplanes would incur over the life of the airplane.
    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 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 copy of the final 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, 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 removing AD 90-12-08, Amendment 39-
6622, and by adding a new airworthiness directive (AD) to read as 
follows:

96-09-04  De Havilland: Amendment 39-9578. Docket No. 95-CE-47-AD; 
Supersedes AD 90-12-08, Amendment 39-6622.

    Applicability: Model DHC-3 airplanes (all serial numbers), 
certificated in any category, that do not have Modification 3/935 
incorporated in accordance with de Havilland Service Bulletin (SB) 
number (No.) 3/50, Revision A, dated February 17, 1995.


[[Page 19808]]


    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: Within the next 3 calendar months after the 
effective date of this AD, unless already accomplished (compliance 
with AD 90-12-08), and thereafter at intervals not to exceed 24 
calendar months.
    To prevent failure of the tailplane structure caused by cracked 
tailplane main rib forward flanges or main rib forward lower flanges 
at the tailplane front attachment fitting, which, if not detected 
and corrected, could result in loss of control of the airplane, 
accomplish the following:
    (a) Inspect, using dye penetrant methods, the tailplane main rib 
forward flanges and the main rib forward lower flanges at the 
tailplane front attachment fitting in accordance with the 
ACCOMPLISHMENT INSTRUCTIONS section of de Havilland SB No. 3/46, 
Revision B, dated December 1, 1989.

    Note 2: Pay particular attention to the front attachment fitting 
area.

    (b) Prior to further flight, repair any tailplane main rib 
forward flange or main rib forward lower flange found cracked during 
any inspection required by this AD. Accomplish this repair in 
accordance with the ACCOMPLISHMENT INSTRUCTIONS section of de 
Havilland SB No. 3/46, Revision B, dated December 1, 1989.
    (c) Installing tailplane root rib angles and plates of improved 
design (Modification 3/935) in accordance with de Havilland SB 3/50, 
Revision A, dated February 17, 1995, terminates the repetitive 
inspection requirement of this AD. Modification 3/935 may be 
incorporated at any time provided that any tailplane main rib 
forward flange or main rib forward lower flange found cracked during 
any inspection required by this AD is repaired.
    (d) 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.
    (e) 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 
Certification Office, 10 5th St., 3rd Floor, Valley Stream, New York 
11581. The request shall be forwarded through an appropriate FAA 
Maintenance Inspector, who may add comments and then send it to the 
Manager, New York Aircraft Certification Office.

    Note 3: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the New York Aircraft Certification Office.

    (f) Alternative methods of compliance approved in accordance 
with AD 90-12-08 (superseded by this action) are considered approved 
as alternative methods of compliance with this AD.
    (g) The inspections, repairs, and replacements required by this 
AD shall be done in accordance with de Havilland Service Bulletin 
No. 3/46, Revision B, dated December 1, 1989, and de Havilland 
Service Bulletin No. 3/50, Revision A, dated February 17, 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. (the parent company 
of de Havilland), Bombardier Regional Aircraft Division, Garrett 
Boulevard, Downsview, Ontario, Canada M3K 1Y5; telephone (416) 633-
7310. Copies may be inspected at the FAA, Central Region, Office of 
the Assistant Chief Counsel, Room 1558, 601 E. 12th Street, Kansas 
City, Missouri, or at the Office of the Federal Register, 800 North 
Capitol Street, NW., 7th Floor, suite 700, Washington, DC.
    (h) This amendment supersedes AD 90-12-08, Amendment 39-6622.
    (i) This amendment (39-9578) becomes effective on May 17, 1996.

    Issued in Kansas City, Missouri, on April 18, 1996.
Henry A. Armstrong,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 96-10076 Filed 5-2-96; 8:45 am]
BILLING CODE 4910-13-U