Airworthiness directives: Pilatus Aircraft Ltd.,
[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]
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
[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.
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
Total cost per Labor cost
Parts cost
airplane
Total cost on U.S. operators
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..
Forward Dihedral Fitting Replacement
Labor cost
Parts cost
Total cost per airplane
93 workhours per fitting (2 fittings per $142 per replacement fitting $5,722 per fitting. airplane) x $60 per hour = $5,580 per fitting.
Aft Dihedral Fitting Replacement and Modification
Total cost per Labor cost
Parts cost
airplane
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.
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.
Model
Manufacturer serial Nos. (MSN)
PC-7................................... 101 through 618.
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:
Actions
Compliance
Procedures
(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).
(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
(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.
(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.
(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
(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.
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]
BILLING CODE 4910-13-P
