AD 2001-22-15

This amendment adopts a new airworthiness directive (AD) that applies to all Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC-12/45 airplanes. This AD requires you to inspect the cargo doors to identify front and rear end frames with plain lightening holes and install reinforcing plates on any frame with plain lightening 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 cracking at the edges of the unflanged lightening holes, which could result in major structural damage to the airplane. Such damage could result in possible loss of control of the airplane.

Final rule

2001-22-15 Pilatus Aircraft Ltd.: Amendment 39-12494; Docket No. 2001-CE-24-AD.

(a) What airplanes are affected by this AD? This AD affects Models PC-12 and PC-12/45 airplanes, all serial numbers, that are certificated in any category.

(b) Who must comply with this AD? Anyone who wishes to operate any of the above airplanes must comply with this AD.

(c) What problem does this AD address? The actions specified by this AD are intended to prevent cracking at the edges of the unflanged lightening holes, which could result in major structural damage to the airplane. Such damage could result in possible loss of control of the airplane.

(d) What actions must I accomplish to address this problem? To address this problem, you must accomplish the following:

Actions
Compliance
Procedures
(1) For manufacturer serial numbers (MSN) 101 through370, inspect the front and rear frames of the cargo door for lightening holes with plain rims.
Within the next 50hours time-in-service (TIS) after December 26, 2001(the effective date of this AD).
In accordance with the Accomplishment Instructions section of Pilatus Service Bulletin No. 52-004, dated April 20, 2001.
(2) If, during the inspection required in paragraph (d)(1) of this AD, a plain rim is found, install a reinforcing plate.
Prior to further flight after the inspection required in paragraph (d)(1) of this AD.
In accordance with the Accomplishment
Instructions section of Pilatus Service Bulletin No. 52-004, dated April 20, 2001.
(3) For all serial numbered airplanes, do not install any cargo door, part-number (P/N) 552.30.12.051 or P/N 552.30.12.052 (or FAA-approved equivalent part number), unless it has been inspected as required in paragraph (d)(1) of this AD and modified as required in paragraph (d)(2) of this AD.
As of December 26, 2001 (the effective date of this AD).
In accordance with the Accomplishment Instructions section of Pilatus Service Bulletin No. 52-004, dated April 20, 2001.

(e) Can I comply with this AD in any other way? You may use an alternative method of compliance or adjust the compliance time if:

(1) Your alternative method of compliance provides an equivalent level of safety; and

(2) The Manager, Small Airplane Directorate, approves your alternative. Submit your request through an FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Small Airplane Directorate.

Note 1: This AD applies to each airplane identified in paragraph (a) of this AD, 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 (e) 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 you have not eliminated the unsafe condition, specific actions you propose to address it.

(f) Where can I get information about 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.

(g) What if I need to fly the airplane to another location to comply with this AD? The FAA can issue a special flight permit under sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate your airplane to a location where you can accomplish the requirements of this AD.

(h) Are any service bulletins incorporated into this AD by reference? Actions required by this AD must be done in accordance with Pilatus Service Bulletin No. 52-004, dated April 20, 2001. The Director of the Federal Register approved this incorporation by reference under 5 U.S.C. 552(a) and 1 CFR part 51. You can get copies from Pilatus Aircraft Ltd., Customer Liaison Manager, CH-6371 Stans, Switzerland; or from Pilatus Business Aircraft Ltd., Product Support Department, 11755 Airport Way, Broomfield, Colorado 80021. You can look at copies at the FAA, Central Region, Office of the Regional Counsel, 901 Locust, Room 506, Kansas City, Missouri, or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

(i) When does this amendment become effective? This amendment becomes effective on December 26, 2001.

Note 2: The subject of this AD is addressed in Swiss AD HB 2001-389, dated June 25, 2001.

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 all Pilatus Models PC-12 and PC-12/45 airplanes. The FOCA reports that, during production, some PC-12 and PC-12/45 airplanes were equipped with cargo doors that do not have reinforcing flanges on the lightening holes in the front and rear end of the cargo door frames.

What is the potential impact if FAA took no action? If not detected and corrected, cracking at the edges of the unflanged lightening holes could result in major structural damage to the airplane. Such damage could result in possible 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 all Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 airplanes. This proposal was published in the Federal Register as a notice of proposed rulemaking (NPRM) on August 22, 2001 (66 FR 44093). The NPRM proposed to require you to inspect the cargo doors to identify front and rear end frames with plain lightening holes; and install reinforcing plates on any frame with plain lightening holes.

The Swiss AD and the manufacturer's service information applies to manufacturer serial numbers (MSN) 301 through 370 and all part-number (P/N) 552.30.12.051 and P/N 552.30.12.052, held as spares. We are expanding the applicability of this AD to all serial numbered airplanes. We are expanding the inspection and installation actions to cover MSN 101 through MSN 370, instead of MSN 301 through MSN 370, because these cargo doors may have been installed on MSN 101 through MSN 370 through field approval or other methods. Since cargo doors, part-number P/N 552.30.12.051 and P/N 552.30.12.052, held as spares, may be installed on airplanes not coveredby the applicability of the service information, the cargo doors on all serial numbered airplanes will have to be inspected and modified if necessary, prior to installation.

Was the public invited to comment? The FAA encouraged interested persons to participate in the making of this amendment. We did not receive any comments on the proposed rule or on our determination of the cost to the public.

FAA's Determination

What is FAA's final determination on this issue? After careful review of all available information related to the subject presented above, we have determined that air safety and the public interest require the adoption of the rule 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.

Cost Impact

How many airplanes does this AD impact? We estimate that this AD affects 230 airplanes in the U.S. registry.

What is the cost impact of this AD on owners/operators of the affected airplanes? We estimate the following costs to accomplish the inspection:

Labor cost
Parts cost
Total cost per airplane
Total cost on U.S. operators
1 workhour x $60 per hour = $60
No parts required for the inspection.
$60
$13,800.

We estimate the following costs to accomplish any necessary modifications that will be required based on the results of the inspection. We have no way of determining the number of airplanes that may need such modification:

Labor cost
Parts cost
Total cost per airplane
2 workhours x $60 per hour = $120
Provided by the manufacturer free of charge.
$120.

Regulatory Impact

Does this AD impact various entities? The regulations adopted herein will not have a substantial direct effect on the States, on the relationship between the national government and theStates, or on the distribution of power and responsibilities among the various levels of government. Therefore, it is determined that this final rule does not have federalism implications under Executive Order 13132.

Does this AD involve a significant rule or regulatory action? For the reasons discussed above, I certify that this action (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. A copy of the final evaluation prepared for this action is contained in the Rules Docket. A copy of it may be obtained by contacting the Rules Docket at the location provided under the caption ADDRESSES.

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 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. FAA amends Sec. 39.13 by adding a new AD to read as follows: