AD 2007-03-08

final rule

Airworthiness Directives; Pilatus Aircraft Ltd., PC-6 Series Airplanes

AD Number
2007-03-08
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Docket No. FAA-2006-25929 Directorate Identifier 2006-CE-54-AD
FR Citation
72 FR 4635

Applicability

TypeManufacturerModelDetails
aircraft Pilatus Various Airworthiness Directives; Pilatus Aircraft Ltd., PC-6 Series Airplanes
aircraft Aviat Various Airworthiness Directives; Pilatus Aircraft Ltd., PC-6 Series Airplanes

Unsafe Condition

Exfoliation corrosion in the fittings installed exterior to the bottom skin of the wing skin.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Inspect the fittings for exfoliation corrosion. Replace any affected fittings as necessary.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

Before further flight.

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

Pilatus Aircraft Ltd., PC-6 Series Airplanes.

AI-generated summary from the source AD text. Verify against the official source before acting.

Federal Register Abstract

We are adopting a new airworthiness directive (AD) for the products listed above. This AD results from mandatory continuing airworthiness information (MCAI) issued by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as the discovery of exfoliation corrosion in the fittings of some PC-6 airplanes. These fittings are installed exterior to the bottom skin of the wing skin. If not corrected, undetected corrosion in this area could lead to failure of the fitting and subsequent loss of control of the airplane. We are issuing this AD to require actions to correct the unsafe condition on these products.

Document Text

Show stored source text (verify against official source)
[Federal Register Volume 72, Number 21 (Thursday, February 1, 2007)]
[Rules and Regulations]
[Pages 4635-4637]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: E7-1494]



[[Page 4635]]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2006-25929 Directorate Identifier 2006-CE-54-AD; 
Amendment 39-14919; AD 2007-03-08]
RIN 2120-AA64


Airworthiness Directives; Pilatus Aircraft Ltd., PC-6 Series 
Airplanes

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

ACTION: Final rule.

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

SUMMARY: We are adopting a new airworthiness directive (AD) for the 
products listed above. This AD results from mandatory continuing 
airworthiness information (MCAI) issued by an aviation authority of 
another country to identify and correct an unsafe condition on an 
aviation product. The MCAI describes the unsafe condition as the 
discovery of exfoliation corrosion in the fittings of some PC-6 
airplanes. These fittings are installed exterior to the bottom skin of 
the wing skin. If not corrected, undetected corrosion in this area 
could lead to failure of the fitting and subsequent loss of control of 
the airplane. We are issuing this AD to require actions to correct the 
unsafe condition on these products.

DATES: This AD becomes effective March 8, 2007.
    The Director of the Federal Register approved the incorporation by 
reference of certain publications listed in this AD as of March 8, 
2007.

ADDRESSES: You may examine the AD docket on the Internet at <a href="http://dms.dot.gov">http://dms.dot.gov</a> or in person at the Docket Management Facility, U.S. 
Department of Transportation, 400 Seventh Street, SW., Nassif Building, 
Room PL-401, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Doug Rudolph, Aerospace Engineer, FAA, 
Small Airplane Directorate, 901 Locust Street, Room 301, Kansas City, 
Missouri 64106; telephone: (816) 329-4059; fax: (816) 329-4090.

SUPPLEMENTARY INFORMATION:

Streamlined Issuance of AD

    The FAA is implementing a new process for streamlining the issuance 
of ADs related to MCAI. The streamlined process will allow us to adopt 
MCAI safety requirements in a more efficient manner and will reduce 
safety risks to the public. This process continues to follow all FAA AD 
issuance processes to meet legal, economic, Administrative Procedure 
Act, and Federal Register requirements. We also continue to meet our 
technical decision-making responsibilities to identify and correct 
unsafe conditions on U.S.-certificated products.
    This AD references the MCAI and related service information that we 
considered in forming the engineering basis to correct the unsafe 
condition. The AD contains text copied from the MCAI and for this 
reason might not follow our plain language principles.

Discussion

    We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR 
part 39 to include an AD that would apply to the specified products. 
That NPRM was published in the Federal Register on November 3, 2006 (71 
FR 64653). That NPRM proposed to require repetitive inspections of the 
wing strut fitting and the replacement of corroded wing strut fittings 
with new retrofit wing strut fittings.

Comments

    We gave the public the opportunity to participate in developing 
this AD. We have considered the comments received.

Comment Issue: Summary

    Clay Lacy asks if there is a planned hourly minimum or just 
calendar time for the compliance. He notes that he has a PC-6 that was 
built by Fairchild in 1967, has only 1,600 hours total time, and has 
always been hangared. Mr. Lacy added, ``We have never detected any 
corrosion at any location.''
    We are relying on the Federal Office for Civil Aviation (FOCA), 
which is the state of design authority, and the manufacturer's 
(Pilatus) determination that calendar time compliance for this type of 
corrosion inspection is appropriate. The FOCA AD requires a one-time 
inspection, and the corresponding service bulletin (SB) states the 
required repetitive inspection will be included in Chapter 5 of the 
Aircraft Maintenance Manual (AMM). Both initial and repetitive 
compliance times are specified in calendar time. We do not have 
information for this issue to correlate between Time-In-Service (TIS) 
and calendar time.

Comment Issue: What Prompted AD

    Clay Lacy states if possible he would like more information that 
prompted this proposed AD.
    Further information on what prompted this proposed AD may be found 
in the Docket Management System (DMS). This action was initiated as a 
result of FOCA AD HB-2006-400. We have checked the DMS and this 
document is electronically available.

Conclusion

    We reviewed the available data, including the comments received, 
and determined that air safety and the public interest require adopting 
the AD as proposed.

Differences Between This AD and the MCAI or Service Information

    We have reviewed the MCAI and related service information and, in 
general, agree with their substance. But we might have found it 
necessary to use different words from those in the MCAI to ensure the 
AD is clear for U.S. operators and is enforceable. In making these 
changes, we do not intend to differ substantively from the information 
provided in the MCAI and related service information.
    We might also have required different actions in this AD from those 
in the MCAI in order to follow FAA policies. Any such differences are 
described in a separate paragraph of the AD, and take precedence over 
the actions copied from the MCAI.

Costs of Compliance

    We estimate that this AD will affect about 49 products of U.S. 
registry. We also estimate that it will take 27 work-hours per product 
to comply with this AD. The average labor rate is $80 per work-hour. 
Required parts will cost about $2,500 per wing per product. Where the 
service information lists required parts costs that are covered under 
warranty, we have assumed that there will be no charge for these parts. 
As we do not control warranty coverage for affected parties, some 
parties may incur costs higher than estimated here. Based on these 
figures, we estimate the cost of this AD to the U.S. operators to be 
$350,840 or $7,160 per product.

Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I, section 106, describes the 
authority of the FAA Administrator. ``Subtitle VII: Aviation 
Programs,'' describes in more detail the scope of the Agency's 
authority.
    We are issuing this rulemaking under the authority described in 
``Subtitle VII, Part A, Subpart III, Section 44701: General 
requirements.'' Under that section, Congress charges the FAA with 
promoting safe flight of civil aircraft in air commerce by prescribing 
regulations for practices, methods, and procedures the Administrator 
finds necessary for safety in air commerce. This regulation

[[Page 4636]]

is within the scope of that authority because it addresses an unsafe 
condition that is likely to exist or develop on products identified in 
this rulemaking action.

Regulatory Findings

    We 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.
    For the reasons discussed above, I certify this AD:
    (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.
    We prepared a regulatory evaluation of the estimated costs to 
comply with this AD and placed it in the AD Docket.

Examining the AD Docket

    You may examine the AD docket on the Internet at <a href="http://dms.dot.gov">http://dms.dot.gov</a>; or in person at the Docket Management Facility between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD 
docket contains the NPRM, the regulatory evaluation, any comments 
received, and other information. The street address for the Docket 
Office (telephone (800) 647-5227) is in the ADDRESSES section. Comments 
will be available in the AD docket shortly after receipt.

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 FAA amends 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. The FAA amends Sec.  39.13 by adding the following new AD:

2007-03-08 Pilatus Aircraft Ltd., PC-6 Series Airplanes: Amendment 
39-14919; Docket No. FAA-2006-25929; Directorate Identifier 2006-CE-
54-AD.

Effective Date

    (a) This airworthiness directive (AD) becomes effective March 8, 
2007.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Models PC-6, PC-6-H1, PC-6-H2, PC-6/350, 
PC-6/350-H1, PC-6/350-H2, PC-6/A, PC-6/A-H1, PC-6/A-H2, PC-6/B-H2, 
PC-6/B1-H2, PC-6/B2-H2, PC-6/B2-H4, PC-6/C-H2, and PC-6/C1-H2 
airplanes; manufacturer serial numbers (MSN) 101 through 949, MSN 
951, and MSN 2001 through 2092; that are certificated in any 
category. These airplanes are also identified as Fairchild Republic 
Company PC-6 airplanes, Fairchild Industries PC-6 airplanes, 
Fairchild Heli Porter PC-6 airplanes, or Fairchild-Hiller 
Corporation PC-6 airplanes.

Reason

    (d) The mandatory continuing airworthiness information (MCAI) 
states that exfoliation corrosion in the fittings of some PC-6 
airplanes was found. These fittings are installed exterior to the 
bottom skin of the wing skin. If not corrected, undetected corrosion 
in this area could lead to failure of the fitting and subsequent 
loss of control of the airplane.

Actions and Compliance

    (e) Unless already done, do the following actions.
    (1) Within 12 months after the effective date of this AD and 
repetitively thereafter at intervals not to exceed 12 months, 
perform an inspection required by paragraph 3.B.(2) of PILATUS PC-6 
Service Bulletin (SB) No. 57-003, dated June 13, 2006, of the 
fittings Part Number (P/N) 6102.0041.00, P/N 111.35.06.055 or P/N 
111.35.06.056 for signs of corrosion. Repair of minor surface 
corrosion is permitted according to the Repair and Overhaul Manual 
(ROM) (Report No. 1391), Chap. 2 and 4. Corrosion outside these 
limits is not permitted.
    (2) If during any of the inspections required by paragraph 
(e)(1) of this AD, any minor surface corrosion is found, prior to 
further flight, remove the minor surface corrosion (Ref. ROM. Chap. 
2 and 4).
    (3) If during any of the inspections required by paragraph 
(e)(1) of this AD, any corrosion out of limits is found (Ref. ROM, 
Chap. 2 and 4), prior to further flight, replace the fittings in 
accordance with paragraph 4 of PILATUS PC-6 SB No. 57-003, dated 
June 13, 2006, with new (retrofit) fittings P/N 111.35.06.185 and/or 
P/N 111.35.06.186.
    (4) Replacement of the fittings with new (improved) fittings P/N 
111.35.06.185 (left hand side) and/or 111.35.06.186 (right hand 
side) terminates the repetitive inspection for that side.

FAA AD Differences

    Note: This AD differs from the MCAI and/or service information 
as follows:
    (1) The FAA AD is requiring repetitive inspections, not just a 
one-time inspection as required in the MCAI.
    (2) The Service Bulletin specifies ``subsequent inspections for 
corrosion will be included in Chapter 5 of the Aircraft Maintenance 
Manual (AMM).'' The only way we (FAA) can mandate these repetitive 
inspections is through an AD.

Other FAA AD Provisions

    (f) The following provisions also apply to this AD:
    (1) Alternative Methods of Compliance (AMOCs): The Manager, 
Standards Staff, FAA, ATTN: Doug Rudolph, Aerospace Engineer, FAA, 
Small Airplane Directorate, 901 Locust, Room 301, Kansas City, 
Missouri 64106; telephone: (816) 329-4059; fax: (816) 329-4090, has 
the authority to approve AMOCs for this AD, if requested using the 
procedures found in 14 CFR 39.19.
    (2) Airworthy Product: For any requirement in this AD to obtain 
corrective actions from a manufacturer or other source, use these 
actions if they are FAA-approved. Corrective actions are considered 
FAA-approved if they are approved by the State of Design Authority 
(or their delegated agent). You are required to assure the product 
is airworthy before it is returned to service.
    (3) Reporting Requirements: For any reporting requirement in 
this AD, under the provisions of the Paperwork Reduction Act (44 
U.S.C. 3501 et.seq.), the Office of Management and Budget (OMB) has 
approved the information collection requirements and has assigned 
OMB Control Number 2120-0056.

Related Information

    (g) Refer to FOCA AD HB-2006-400, effective date September 28, 
2006, which references Pilatus Aircraft Ltd. SB No. 57-003, dated 
June 13, 2006, for related information.

Material Incorporated by Reference

    (h) You must use PILATUS PC-6 Service Bulletin (SB) No. 57-003, 
dated June 13, 2006, to do the actions required by this AD, unless 
the AD specifies otherwise.
    (1) The Director of the Federal Register approved the 
incorporation by reference of this service information under 5 
U.S.C. 552(a) and 1 CFR part 51.
    (2) For service information identified in this AD, contact 
Pilatus Aircraft Ltd., Customer Liaison Manager, CH-6371 Stans, 
Switzerland; telephone: +41 41 619 63 19; fax: +41 41 619 6224.
    (3) You may review copies at the FAA, Central Region, Office of 
the Regional Counsel, 901 Locust, Room 506, Kansas City, Missouri 
64106; or at the National Archives and Records Administration 
(NARA). For information on the availability of this material at 
NARA, call 202-741-6030, or go to: <a href="http://www.archives.gov/federal-register/cfr/ibr-locations.html">http://www.archives.gov/federal-register/cfr/ibr-locations.html</a>.


[[Page 4637]]


    Issued in Kansas City, Missouri, on January 24, 2007.
Kim Smith,
Manager, Small Airplane Directorate, Aircraft Certification Service.
 [FR Doc. E7-1494 Filed 1-31-07; 8:45 am]
BILLING CODE 4910-13-P

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