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

ACTION: Final rule.

SUMMARY: We are superseding an existing 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:

Field reports have indicated that the possibility exists that both Primary Flight Displays (PFDs) could indicate a roll attitude offset of up to 10 degrees in the same direction if an accelerated turn onto the active runway is performed immediately followed by take-off. In addition, annunciated heading splits have been reported. This condition has been reported to correct itself after several minutes.
Additionally, if the aeroplane is operating in geographical latitudes with low horizontal magnetic field strength, incorrect heading may be displayed if the ADAHRS switches from GPS track to magnetometer heading while the aeroplane is on the ground.

This situation, if not corrected, could result in an undesired bank angle, heading splits and/or incorrect heading, which would constitute an unsafe condition.

We are issuing this AD to require actions to correct the unsafe condition on these products.

DATES: This AD becomes effective April 1, 2010.
On April 1, 2010, the Director of the Federal Register approved the incorporation by reference of Honeywell International Inc. Service Bulletin KSG 7200-34-09, Revision 0, dated September 24, 2009; and Pilatus Aircraft Ltd. Pilatus PC-12 Service Bulletin No.: 34-022, dated October 5, 2009, listed in this AD.
As of April 20, 2009 (74 FR 17384, April 15, 2009), the Director of the Federal Register approved the incorporation by reference of Pilatus Aircraft Ltd. Temporary Revision No. 11 to PC-12/47E Pilot's Operating Handbook, Report No. 02277, dated March 18, 2009, listed in this AD.

ADDRESSES: You may examine the AD docket on the Internet at http:// www.regulations.gov or in person at the Docket Management Facility, U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT: Doug Rudolph, Aerospace Engineer, FAA, Small Airplane Directorate, 901 Locust, Room 301, ACE-112, Kansas City, Missouri 64106; telephone: (816) 329-4059; fax: (816) 329-4090.

SUPPLEMENTARY INFORMATION:

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 December 10, 2009 (74 FR 65493), and proposed to supersede AD 2009-08-10, Amendment 39- 15883 (74 FR 17384, April 15, 2009). That NPRM proposed to correct an unsafe condition for the specified products. The MCAI states that:

Field reports have indicated that the possibility exists that both Primary Flight Displays (PFDs) could indicate a roll attitude offset of up to 10 degrees in the same direction if an accelerated turn onto the active runway is performed immediately followed by take-off. In addition, annunciated heading splits have been reported. This condition has been reported to correct itself after several minutes.
Additionally, if the aeroplane is operating in geographical latitudes with low horizontal magnetic field strength, incorrect heading may be displayed if the ADAHRS switches from GPS track to magnetometer heading while the aeroplane is on the ground.
This situation, if not corrected, could result in an undesired bank angle, heading splits and/or incorrect heading, which would constitute an unsafe condition.
As a short-term interim measure, AD 2009-0028-E has been released in February 2009 to limit at 30[deg] the bank angle during climb. Afterwards, as a result of the ongoing investigation, the problem has been temporarily addressed with some limitations in the take-off procedure. These limitations have been mandated by AD 2009- 0080-E which superseded AD 2009-0028-E.
In order to terminate the operational limitations, an updated ADAHRS version with improved software was developed.
For the reasons described above, this AD supersedes AD 2009- 0080-E and mandates as a terminating action either an update of the ADAHRS software or the replacement of the ADAHRS unit.
From MSN 1181 and subsequent an improved ADAHRS unit was implemented during production.

You may obtain further information by examining the MCAI in the AD docket.

Comments

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

Comment Issue No. 1: Limit the Applicability to Manufacturer Serial Numbers (MSN) 545, and 1001 Through 1180

Mr. Scott Lania, Alpha Flying, Inc., requests limiting the applicability to MSN 545, and 1001 through 1180, which have the affected air data, attitude, and heading reference system (ADAHRS) unit installed. Paragraph (f)(4) of the proposed AD addresses the issue of installing one of the affected ADAHRS units on other Pilatus Model PC- 12/47E airplanes.
Mr. Lania requests this change in the applicability since Pilatus is installing a new version of the ADAHARS at production on MSN 1181 and subsequent.
The FAA partially agrees with the commenter. We agree that Pilatus is installing a new version of the ADAHRS in production. However, we disagree with changing the applicability of this AD. To prevent future installation of the defective ADAHARS unit on airplanes, the applicability must be for all airplanes, thus preventing the introduction of the unsafe condition on these airplanes. Paragraph (f)(4), which prohibits installation of the affected ADAHRS on other Pilatus Model PC-12/47E airplanes, would not apply unless the applicability was for all airplanes.
We are not changing the final rule AD action based on this comment.

Comment Issue No. 2: Use "Serviceable'' or "Modified'' in Describing the ADAHRS Unit

Mr. Lania also requests that the word "new'' in paragraph (f)(2)(ii) of the Actions and Compliance section of the proposed AD be replaced with the word "serviceable'' or "modified.''
Mr. Lania states that when accomplishing the Pilatus service bulletin to comply with this AD, the ADAHRS unit is not being replaced with a new unit; instead, it is being modified with upgraded software and the data plate of the ADAHRS unit is being changed to the new part number (P/N). Mr. Lania concludes that in the accomplishment of this AD on all the affected airplanes, relatively few, if any, of the ADAHRS units will be replaced with new units.
We disagree with the commenter. The word "new'' refers to a new Honeywell unit from the manufacturer, so the word "serviceable'' is not an appropriate substitution here. We believe the commenter's intent is to use modified components instead of getting a new ADAHRS unit. The use of modified components is addressed in paragraph (f)(2)(i) of the proposed AD. In paragraph (f)(2)(i) of the proposed AD, the operator may accomplish the Honeywell service bulletin, which changes the P/N after the unit gets new software uploaded.
We are not changing the final rule AD action based on this comment.

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 highlighted in a Note within the AD.

Costs of Compliance

We estimate that this AD will affect 50 products of U.S. registry. We also estimate that it will take about 6 work-hours per product to comply with the basic requirements of this AD. The average labor rate is $85 per work-hour. Required parts will cost about $0 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 $25,500 or $510 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 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 http:// www.regulations.gov; 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) 647-5527) 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

Accordingly, under the authority delegated to me by the Administrator, the FAA amends 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. The FAA amends Sec. 39.13 by removing Amendment 39-15883 (74 FR 17384, April 15, 2009) and adding the following new AD: