[Federal Register Volume 62, Number 88 (Wednesday, May 7, 1997)]
[Rules and Regulations]
[Pages 24810-24812]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-11880]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 93-CE-45-AD; Amendment 39-10016; AD 97-07-10 R1]
RIN 2120-AA64
Airworthiness Directives; de Havilland DHC-6 Series Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule; correction.
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SUMMARY: This document clarifies information in an existing
airworthiness directive (AD) that applies to de Havilland DHC-6 series
airplanes that do not have a certain wing strut modification
(Modification 6/1581) incorporated. That AD currently requires
inspecting the wing struts for cracks or damage (chafing, etc.),
replacing wing struts that are found damaged beyond certain limits or
are found cracked, and incorporating Modification No. 6/1581 to prevent
future chafing damage. The actions specified in that AD are intended to
prevent failure of the wing struts, which could result in loss of
control of the airplane. This document clarifies the requirements of
the current AD by eliminating all reference to repetitive inspections.
The AD results from several reports of wing strut damage caused by the
upper fairing rubbing against the wing strut.
DATES: Effective May 23, 1997.
The incorporation by reference of certain publications listed in
the regulations was approved previously by the Director of the Federal
Register as of May 23, 1997 (62 FR 15373).
FOR FURTHER INFORMATION CONTACT: Jon Hjelm, Aerospace Engineer, FAA,
New
[[Page 24811]]
York Aircraft Certification Office, 10 Fifth Street, 3rd Floor, Valley
Stream, New York 11581; telephone (516) 256-7523; facsimile (516) 568-
2716.
SUPPLEMENTARY INFORMATION: On March 26, 1997, the Federal Aviation
Administration (FAA) issued AD 97-07-10, Amendment 39-9984 (62 FR
15373, April 1, 1997), which applies to de Havilland DHC-6 series
airplanes. That AD requires inspecting the wing struts for cracks or
damage (chafing, etc.), replacing wing struts that are found damaged
beyond certain limits or are found cracked, and incorporating
Modification No. 6/1581 to prevent future chafing damage. Modification
No. 6/1581 consists of installing a preformed nylon shield around the
area of each wing strut at the upper end closest to the wing.
Accomplishment of the inspection and modification is required in
accordance with de Havilland Service Bulletin No. 6/342, dated February
23, 1976.
That AD resulted from several reports of wing strut damage caused
by the upper fairing rubbing against the wing strut on the affected
airplanes. The actions required by that AD are intended to prevent
failure of the wing struts, which could result in loss of control of
the airplane.
Need for the Correction
Since the issuance of that AD, the FAA noticed that paragraph
(b)(1) of the AD is unnecessary. This paragraph reads:
Incorporating Modification No. 6/1581 eliminates the repetitive
inspection requirement of this AD.
Repetitive inspections are not required by AD 97-07-10. Leaving
this paragraph in the AD could lead to confusion among the operators of
the affected airplanes as to what is the intent of the AD. In addition
to deleting paragraph (b)(1) of this AD, paragraph (b)(2) will become
part of paragraph (b).
Correction of Publication
This document clarifies the requirements of AD 97-07-10, and
correctly adds the AD as an amendment to section 39.13 of the Federal
Aviation Regulations (14 CFR 39.13).
The AD is being reprinted in its entirety for the convenience of
affected operators. The effective date of the AD remains May 23, 1997.
Since this action only clarifies a current requirement, it has no
adverse economic impact and imposes no additional burden on any person.
Therefore, the FAA has determined that notice and public procedures are
unnecessary.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
Adoption of the Correction
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 97-07-10, Amendment 39-
9984 (62 FR 15373, April 1, 1997), and by adding a new airworthiness
directive (AD), to read as follows:
97-07-10 R1 DeHavilland: Amendment 39-10016; Docket No. 93-CE-45-
AD. Revises AD 97-07-10, Amendment 39-9984.
Applicability: Models DHC-6-1, DHC-6-100, DHC-6-200, and DHC-6-
300 airplanes (all serial numbers), certificated in any category,
that do not have Modification No. 6/1581 incorporated.
Note 1: Modification No. 6/1581 consists of installing a
preformed nylon shield around the area of each wing strut at the
upper end closest to the wing.
Note 2: 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, unless already accomplished.
To prevent failure of the wing struts, which could result in
loss of control of the airplane, accomplish the following:
(a) Within the next 100 hours time-in-service (TIS) after the
effective date of this AD, inspect the wing struts, part number (P/
N) C6W1005 (or FAA-approved equivalent), for cracks or damage
(chafing, etc.) in accordance with the ACCOMPLISHMENT INSTRUCTIONS
section of de Havilland Service Bulletin (SB) No. 6/342, dated
February 23, 1976.
(1) If damage is found on a wing strut that exceeds 0.025-inch
in depth, exceeds a total length of 5 inches, or where any two
places of damage are separated by less than 10 inches of undamaged
surface over the length of the strut, prior to further flight,
replace the wing strut with an airworthy FAA-approved part in
accordance with the applicable maintenance manual.
(2) If any crack is found, prior to further flight, replace the
wing strut with an airworthy FAA-approved part in accordance with
the applicable maintenance manual.
(3) If damage is found on a wing strut that exceeds 0.010-inch
in depth, provided the damage does not exceed 0.025-inch in depth,
the damage does not exceed a total length of 5 inches, and where any
two places of damage are separated by a minimum of 10 inches
undamaged surface over the length of the strut, within 500 hours TIS
after the inspection specified in paragraph (a) of this AD, replace
the wing strut with an airworthy FAA-approved part in accordance
with the applicable maintenance manual.
(b) Within the next 600 hours TIS after the effective date of
this AD, incorporate Modification No. 6/1581 in accordance with the
ACCOMPLISHMENT INSTRUCTIONS section of de Havilland SB No. 6/342,
dated February 23, 1976. Incorporating Modification No. 6/1581 may
be accomplished at any time prior to 600 hours TIS after the
effective date of this AD, at which time it must be incorporated.
(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
compliance times that provides an equivalent level of safety may be
approved by the Manager, New York Aircraft Certification Office
(ACO), FAA, 10 Fifth Street, 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 ACO.
Note 3: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the New York ACO.
(e) The inspections and modification required by this AD shall
be done in accordance with de Havilland Service Bulletin No. 6/342,
dated February 23, 1976. This incorporation by reference was
approved previously by the Director of the Federal Register, in
accordance with 5 U.S.C. 552(a) and 1 CFR part 51, as of May 23,
1997 (62 FR 15373, April 1, 1997). Copies may be obtained from de
Havilland, Inc., 123 Garratt Boulevard, Downsview, Ontario M3K 1Y5
Canada. 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., suite 700, Washington, DC.
(f) This amendment (39-10016) becomes effective on May 23, 1997.
[[Page 24812]]
Issued in Kansas City, Missouri, on May 1, 1997.
Michael Gallagher,
Manager, Small Airplane Directorate, Aircraft Certification Service.
[FR Doc. 97-11880 Filed 5-6-97; 8:45 am]
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