[Federal Register: October 3, 2003 (Volume 68, Number 192)]
[Rules and Regulations]
[Page 57343-57345]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr03oc03-7]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 2003-CE-29-AD; Amendment 39-13323; AD 2003-20-05]
RIN 2120-AA64
Airworthiness Directives; PILATUS Aircraft Ltd. Model PC-7
Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
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SUMMARY: The FAA adopts a new airworthiness directive (AD) for certain
PILATUS Aircraft Ltd. (Pilatus) Model PC-7 airplanes. This AD requires
you to inspect the forward and aft dihedral fittings for cracks and
replace any cracked fitting. This AD also requires you to modify the
aft dihedral fitting and spar-cap bolt holes. This AD is the result of
mandatory continuing airworthiness information (MCAI) issued by the
airworthiness authority for Switzerland. The actions specified by this
AD are intended to prevent cracks from developing in the forward and
aft dihedral fittings, which could result in failure of the wing in
certain maneuvers. Such failure could lead to loss of control of the
airplane.
DATES: This AD becomes effective on November 14, 2003.
The Director of the Federal Register approved the incorporation by
reference of certain publications listed in the regulation as of
November 14, 2003.
ADDRESSES: You may get the service information identified in this AD
from Pilatus Aircraft Ltd., Customer Liaison Manager, CH-6371 Stans,
Switzerland; telephone: +41 41 619 63 19; facsimile: +41 41 619 6224;
or from Pilatus Business Aircraft Ltd., Product Support Department,
11755 Airport Way, Broomfield, Colorado 80021; telephone: (303) 465-
9099; facsimile: (303) 465-6040.
You may view the AD docket at FAA, Central Region, Office of the
Regional Counsel, Attention: Rules Docket No. 2003-CE-29-AD, 901
Locust, Room 506, Kansas City, Missouri 64106. Office hours are 8 a.m.
to 4 p.m., Monday through Friday, except Federal holidays.
FOR FURTHER INFORMATION CONTACT: Doug Rudolph, Aerospace Engineer, FAA,
Small Airplane Directorate, 901 Locust, Room 301, Kansas City, Missouri
64106; telephone: (816) 329-4059; facsimile: (816) 329-4090.
SUPPLEMENTARY INFORMATION:
Discussion
What Events Have Caused This AD?
The Federal Office for Civil Aviation (FOCA), which is the
airworthiness authority for Switzerland, recently notified FAA that an
unsafe condition may exist on certain Pilatus Model PC-7 airplanes. The
FOCA reports that an operator of a similar aircraft type design, which
uses identical dihedral fittings, reported a crack in one fitting. An
inspection of the fleet revealed stress corrosion cracking in six aft
dihedral fittings. Each cracked fitting was found on airplanes that had
logged more than 3,000 hours time-in-service (TIS) or had been in
service for 10 years or more.
What Is the Potential Impact if FAA Took No Action?
Cracks in the forward and aft dihedral fittings could result in
failure of the wing in certain maneuvers. Such failure could lead to
loss of control of the airplane.
Has FAA Taken Any Action to This Point?
We issued a proposal to amend part 39 of the Federal Aviation
Regulations (14 CFR part 39) to include an AD that would apply to
certain Pilatus Model PC-7 airplanes. This proposal was published in
the Federal Register as a notice of proposed rulemaking (NPRM) on July
3, 2003 (68 FR 398970). The NPRM proposed to require you to:
--Inspect the forward and aft dihedral fittings for cracks;
--Replace any cracked fittings found; and
--Modify the aft dihedral fittings and spar-cap bolt holes.
Was the Public Invited To Comment?
We provided the public the opportunity to participate in the
development of this AD. We received no comments on the proposal or on
the determination of the cost to the public.
Conclusion
What Is FAA's Final Determination on This Issue?
We have carefully reviewed the available data and determined that
air safety and the public interest require adopting the AD as proposed
except for minor editorial corrections. We have determined that these
minor corrections:
--Provide the intent that was proposed in the NPRM for correcting the
unsafe condition; and
--Do not add any additional burden upon the public than was already
proposed in the NPRM.
Changes to 14 CFR Part 39--Effect on the AD
How Does the Revision to 14 CFR Part 39 Affect This AD?
On July 10, 2002, the FAA published a new version of 14 CFR part 39
(67 FR 47997, July 22, 2002), which governs the FAA's AD system. This
regulation now includes material that relates to altered products,
special flight permits, and alternative methods of compliance. This
material previously was included in each individual AD. Since this
material is included in 14 CFR part 39, we will not include it in
future AD actions.
Costs of Compliance
How Many Airplanes Does This AD Impact?
We estimate that this AD affects 10 airplanes in the U.S. registry.
[[Page 57344]]
What Is the Cost Impact of This AD on Owners/Operators of the Affected
Airplanes?
We estimate the following costs to accomplish the actions of this
AD:
Inspections
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Total cost per
Labor cost Parts cost airplane Total cost on U.S. operators
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3 workhours per fitting (4 Not applicable....... $180 x 4 fittings per $720 x 10 = $7,200.
fittings per airplane) x $60 per airplane = $720.
hour = $180 per fitting..
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Forward Dihedral Fitting Replacement
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Labor cost Parts cost Total cost per airplane
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93 workhours per fitting (2 fittings per $142 per replacement fitting $5,722 per fitting.
airplane) x $60 per hour = $5,580 per
fitting.
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Aft Dihedral Fitting Replacement and Modification
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Total cost per
Labor cost Parts cost airplane
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20 workhours per fitting for $76 per replacement $1,200 + $76 + $66 =
replacement and fitting and $66 for $1,342 (labor,
modification (2 fittings modification bolts. replacement, and
per airplane) x $60 per modification per
hour = $1,200 per fitting. fitting).
10 workhours per fitting for $600 + $66 = $666
modification only (2 (labor and
fittings per airplane) x modification per
$60 per hour = $600 per fitting).
fitting.
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Compliance Time of This AD
What Is the Compliance Time of This AD?
The compliance time of this AD is whichever occurs later: (1) upon
the accumulation of 3,000 hours time-in-service (TIS) on the dihedral
fittings or 10 years after installation of the dihedral fittings,
whichever occurs first; or (2) within 90 days after the effective date
of this AD.
Why Is the Compliance Time of This AD Presented in Both Hours TIS and
Calendar Time?
Cracking of the dihedral fittings on the affected airplanes is
caused by stress corrosion, which starts as a result of high local
stress incurred through operation. Corrosion can then develop
regardless of whether the airplane is in flight or on the ground. The
cracks may not be noticed initially as a result of the stress loads,
but could then progress as a result of corrosion. The stress incurred
during flight operations or temperature changes could then cause rapid
crack growth. In order to ensure that these stress corrosion cracks do
not go undetected, a compliance time of specific hours TIS and calendar
time is used.
Regulatory Findings
Will This AD Impact Various Entities?
We have determined that this AD will not have federalism
implications under Executive Order 13132. This AD will 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.
Will This AD Involve a Significant Rule or Regulatory Action?
For the reasons discussed above, I certify that this AD:
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. 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.
We prepared a summary of the costs to comply with this AD and
placed it in the AD Docket. You may get a copy of this summary by
sending a request to us at the address listed under ADDRESSES. Include
``AD Docket No. 2003-CE-29-AD'' in your request.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
Adoption of the Amendment
0
Accordingly, under 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
0
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]
0
2. FAA amends Sec. 39.13 by adding a new AD to read as follows:
2003-20-05 Pilatus Aircraft Ltd.: Amendment 39-13323; Docket No.
2003-CE-29-AD.
When Does This AD Become Effective?
(a) This AD becomes effective on November 14, 2003.
Are Any Other ADs Affected by This Action?
(b) None.
[[Page 57345]]
What Airplanes Are Affected by This AD?
(c) This AD affects the following airplane models and serial
numbers that are:
(1) Certificated in any category; and
(2) Equipped with forward and aft dihedral fittings, part number
(P/N) 111.34.07.469, 111.34.07.470, 111.34.07.471, and P/N
111.34.07.472.
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Model Manufacturer serial Nos. (MSN)
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PC-7................................... 101 through 618.
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What Is the Unsafe Condition Presented in This AD?
(d) This AD is the result of mandatory continuing airworthiness
information (MCAI) issued by the airworthiness authority for
Switzerland. The actions specified by this AD are intended to
prevent cracks from developing in the forward and aft dihedral
fittings, which could result in failure of the wing in certain
maneuvers. Such failure could lead to loss of control of the
airplane.
What Must I Do To Address This Problem?
(e) To address this problem, you must accomplish the following:
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Actions Compliance Procedures
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(1) Accomplish the following At whichever of the Inspect in
inspections: following occurs accordance with
(i) Using Impedance-Plane later, unless Pilatus PC-7
Eddy-Current inspection already Service Bulletin
procedures, inspect the aft accomplished: upon No. 57-006,
dihedral fittings, P/N the accumulation of Revision No. 3,
111.34.07.469 and P/N 3,000 hours time-in- dated January 15,
111.34.07.470, for cracks; service (TIS) on 2003.
and. the dihedral
(ii) Using Radiographic fittings or 10
inspection procedures, years after
inspect the forward installation of the
dihedral fittings, P/N dihedral fittings,
111.34.07.471 and P/N whichever occurs
111.34.07.472, for cracks. first; or within 90
days after November
14, 2003 (the
effective date of
this AD).
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(2) If a crack is found in Prior to further Modify in accordance
any aft dihedral fittings, flight after the with Pilatus PC-7
P/N 111.34.07.469 and/or P/ inspection required Service Bulletin
N 111.34.07.470, replace in paragraph (e)(1) No. 57-006,
with an improved fitting, P/ of this AD. Revision No. 3,
N 557.10.09.071 and/or P/N dated January 15,
557.10.09.072 (as 2003.
applicable or FAA-approved
equivalent P/N), and modify
the spar-cap bolt holes
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(3) If no cracks are found Prior to further Modify in accordance
in any aft dihedral flight after the with Pilatus PC-7
fittings, P/N 111.34.07.469 inspection required Service Bulletin
and P/N 111.34.07.470, in paragraph (e)(1) No. 57-006,
modify the fittings and the of this AD. Revision No. 3,
spar-cap bolt holes dated January 15,
2003.
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(4) If cracks are found in Prior to further Not applicable.
any forward dihedral flight after the
fittings, P/N 111.34.07.471 inspection required
and/or P/N 111.34.07.472, in paragraph (e)(1)
replace with a new part of this AD.
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(5) If no cracks are found Not applicable...... Not applicable.
in any forward dihedral
fittings, P/N 111.34.07.471
and P/N 111.34.07.472, no
further action is required
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(6) Only install aft As of November 14, Modify the spar-cap
dihedral fittings that have 2003 (the effective bolt holes in
a P/N of 557.10.09.071 and date of this AD). accordance with
P/N 557.10.09.072. You must Pilatus PC-7
also accomplish the spar- Service Bulletin
cap bolt hole modification No. 57-006,
Revision No. 3,
dated January 15,
2003.
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What About Alternative Methods of Compliance?
(f) You may request a different method of compliance or a
different compliance time for this AD by following the procedures in
14 CFR 39.13. Send your request to the Manager, Standards Office,
Small Airplane Directorate, FAA. For information on any already
approved alternative methods of compliance, contact Doug Rudolph,
Aerospace Engineer, FAA, Small Airplane Directorate, 901 Locust,
Room 301, Kansas City, Missouri 64106; telephone: (816) 329-4059;
facsimile: (816) 329-4090.
Is There Material Incorporated by Reference?
(g) Actions required by this AD must be done in accordance with
Pilatus PC-7 Service Bulletin No. 57-006, Revision No. 3, dated
January 15, 2003. The Director of the Federal Register approved the
incorporation by reference of this service bulletin in accordance
with 5 U.S.C. 552(a) and 1 CFR part 51. You may get a copy from
Pilatus Aircraft Ltd., Customer Liaison Manager, CH-6371 Stans,
Switzerland; telephone: +41 41 619 63 19; facsimile: +41 41 619
6224; or from Pilatus Business Aircraft Ltd., Product Support
Department, 11755 Airport Way, Broomfield, Colorado 80021;
telephone: (303) 465-9099; facsimile: (303) 465-6040. You may review
copies at FAA, Central Region, Office of the Regional Counsel, 901
Locust, Room 506, Kansas City, Missouri 64106; or at the Office of
the Federal Register, 800 North Capitol Street, NW, suite 700,
Washington, DC.
Is There Other Information That Relates to This Subject?
(h) Swiss AD HB 2003-196, dated May 12, 2003, also addresses the
subject of this AD.
Issued in Kansas City, Missouri, on September 24, 2003.
Michael Gallagher,
Manager, Small Airplane Directorate, Aircraft Certification Service.
[FR Doc. 03-24685 Filed 10-2-03; 8:45 am]
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