03-672. Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

This document proposes to adopt a new airworthiness directive (AD) that would apply to certain Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC-12/45 airplanes. This proposed AD would require you to inspect the front and rear surfaces of the pressure dome for damage and cracks, and, if necessary, accomplish repairs. This proposed AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. The actions specified by this proposed AD are intended to detect and correct damage and cracks to the pressure dome, which could lead to rapid decompression.

DATES:

The Federal Aviation Administration (FAA) must receive any comments on this proposed rule on or before February 24, 2003.

ADDRESSES:

Submit comments to FAA, Central Region, Office of the Regional Counsel, Attention: Rules Docket No. 2002-CE-53-AD, 901 Locust, Room 506, Kansas City, Missouri 64106. You may view any comments at this location between 8 a.m. and 4 p.m., Monday through Friday, except Federal holidays. You may also send comments electronically to the following address: [e-mail]. Comments sent electronically must contain “Docket No. 2002-CE-53-AD” in the subject line. If you send comments electronically as attached electronic files, the files must be formatted in Microsoft Word 97 for Windows or ASCII text.

You may get service information that applies to this proposed AD from Pilatus Aircraft Ltd., Customer Liaison Manager, CH-6371 Stans, Switzerland; telephone: [phone]; facsimile: [phone]; or from Pilatus Business Aircraft Ltd., Product Support Department, 11755 Airport Way, Broomfield, Colorado 80021; telephone: [phone]; facsimile: [phone]. You may also view this information at the Rules Docket at the address above.

FOR FURTHER INFORMATION CONTACT:

Doug Rudolph, Aerospace Engineer, FAA, Small Airplane Directorate, 901 Locust, Room 301, Kansas City, Missouri 64106; telephone: [phone]; facsimile: [phone].

SUPPLEMENTARY INFORMATION:

Comments Invited

How Do I Comment on this Proposed AD?

The FAA invites comments on this proposed rule. You may submit whatever written data, views, or arguments you choose. You need to include the proposed rule's docket number and submit your comments to the address specified under the caption ADDRESSES. We will consider all comments received on or before the closing date. We may amend this proposed rule in light of comments received. Factual information that supports your ideas and suggestions is extremely helpful in evaluating the effectiveness of this proposed AD action and determining whether we need to take additional rulemaking action.

Are there any specific portions of this proposed AD I should pay attention to?

The FAA specifically invites comments on the overall regulatory, economic, environmental, and energy aspects of this proposed rule that might suggest a need to modify the proposed rule. You may view all comments we receive before and after the closing date of the proposed rule in the Rules Docket. We will file a report in the Rules Docket that summarizes each contact we have with the public that concerns the substantive parts of this proposed AD.

How Can I Be Sure FAA Receives My Comment?

If you want FAA to acknowledge the receipt of your mailed comments, you must include a self-addressed, stamped postcard. On the postcard, write “Comments to Docket No. 2002-CE-53-AD.” We will date stamp and mail the postcard back to you.

Discussion

What Events Have Caused This Proposed 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 Models PC-12 and PC-12/45 airplanes. The FOCA reports that drill and/or rivet tool damage could have occurred in areas around the edges of the rear pressure dome during assembly of the Models PC-12 and PC-12/45 airplanes.

Pilatus has received 19 reports of damaged pressure domes. The reported damage included nicks and scratches. This type of damage could also occur on the forward surface of the pressure dome.

What Are the Consequences if the Condition Is Not Corrected?

The damage to the pressure dome could result in cracks in the pressure dome and lead to rapid decompression.

Is There Service Information That Applies To This Subject?

Pilatus has issued PC-12 Service Bulletin Number 53-003, Revision No. 1, dated July 26, 2002.

What Are the Provisions of This Service Information?

The service bulletin includes procedures for:

—inspecting the pressure dome for damage/cracks; and

—repairing the pressure dome.

What Action Did the FOCA Take?

The FOCA classified this service bulletin as mandatory and issued Swiss AD Number HB 2002-608, dated November 1, 2002, in order to ensure the continued airworthiness of these airplanes in Switzerland.

Was This in Accordance With the Bilateral Airworthiness Agreement?

These airplane models are manufactured in Switzerland and are type certificated for operation in the United States under the provisions of section 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the applicable bilateral airworthiness agreement.

Pursuant to this bilateral airworthiness agreement, the FOCA has kept FAA informed of the situation described above.

The FAA's Determination and an Explanation of the Provisions of This Proposed AD

What Has FAA Decided?

The FAA has examined the findings of the FOCA; reviewed all available information, including the service information referenced above; and determined that:

—the unsafe condition referenced in this document exists or could develop on other Pilatus Models PC-12 and PC-12/45 airplanes of the same type design that are on the U.S. registry;

—the actions specified in the previously-referenced service information should be accomplished on the affected airplanes; and

—AD action should be taken in order to correct this unsafe condition.

What Would This Proposed AD Require?

This proposed AD would require you to incorporate the actions in the previously-referenced service bulletin.

Cost Impact

How Many Airplanes Would This Proposed AD Impact?

We estimate that this proposed AD affects 280 airplanes in the U.S. registry.

What Would Be the Cost Impact of This Proposed AD on Owners/Operators of the Affected Airplanes?

We estimate the following costs to accomplish the proposed inspection:

Labor cost	Parts cost	Total cost per airplane	Total cost on U.S. operators
8 workhours × $60 per hour = $480	No parts required	$480	$480 × 280 = $134,400

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

Labor cost	Parts cost	Total cost per airplane
16 workhours × $60 per hour = $960	No parts required	$960

Compliance Time of this Proposed AD

What Would Be the Compliance Time of This Proposed AD?

The compliance time of this proposed AD is within 90 days after the effective date of this AD, unless already accomplished.

Why Is the Compliance Time Presented in Calendar Time Instead of Hours Time-in-Service (TIS)?

Failure of the pressure dome is only unsafe during airplane operation. However, this unsafe condition is not a result of the number of times the airplane is operated. The chance of this situation occurring is the same for an airplane with 10 hours TIS as it would be for as airplane with 500 hours TIS. For this reason, FAA has determined that a compliance based on calendar time should be utilized in this AD in order to assure that the unsafe condition is addressed on all airplanes in a reasonable time period.

Regulatory Impact

Would This Proposed AD Impact Various Entities?

The regulations proposed herein would 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. Therefore, it is determined that this proposed rule would not have federalism implications under Executive Order 13132.

Would This Proposed AD Involve a Significant Rule or Regulatory Action?

For the reasons discussed above, I certify that this proposed 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) if promulgated, 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 draft regulatory evaluation prepared for this action has been placed 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
• Safety

The Proposed Amendment

Accordingly, under the authority delegated to me by the Administrator, the Federal Aviation Administration proposes to amend 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.

§ 39.13

[Amended]

2. FAA amends § 39.13 by adding a new airworthiness directive (AD) to read as follows:

Pilatus Aircraft Company Ltd.: Docket No. 2002-CE-53-AD

(a) What airplanes are affected by this AD? This AD affects Models PC-12 and PC-12/45 airplanes, that are certificated in any category, with the following serial numbers: 101 through 380, 382 through 385, 387 through 395, 398 through 406, 408, 409, 413, 415, and 417.

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

(c) What problem does this AD address? The actions specified by this AD are intended to detect and correct damage and cracks to the pressure dome, which could lead to rapid decompression.

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

Actions	Compliance	Procedures
(1) Inspect the pressure dome for crack/nick/scratch damage	Within the next 90 days after the effective date of this AD, unless already accomplished	In accordance with Pilatus Aircraft Ltd. PC-12 Service Bulletin No. 53-003, Revision 1, dated July 26, 2002, and the applicable maintenance manual.
(2) If during the inspection required by paragraph (d)(1) of this AD, type “A” or “B” nick/scratch damage (as specified in the service information) is found, accomplish repairs	Prior to further flight after the inspection in which the type “A” or “B” nick/scratch damage is found	In accordance with Pilatus Aircraft Ltd. PC-12 Service Bulletin No. 53-003, Revision 1, dated July 26, 2002, and the applicable maintenance manual.
(3) Pursuant to paragraph (d)(2) of this AD, if a repair was done in which metal was removed to a depth of more than 0.008 inches (0.2 millimeter) (type “C”), you must obtain approval of the repair scheme from the manufacturer through FAA at the address specified in paragraph (f) of this AD. If you do not receive through FAA an approval within 90 days or 600 takeoff/landings of the repair date, whichever occurs later, the aircraft is restricted to unpressurized flight only	Within 90 days or 600 takeoffs/landings of the repair date, whichever occurs first	In accordance with Pilatus Aircraft Ltd. PC-12 Service Bulletin No. 53-003, Revision 1, dated July 26, 2002, and the applicable maintenance manual.
(4) If during the inspection required by paragraph (d)(1) of this AD, type “C” nick/scratch damage (as specified in the service information) is found, use a 10X magnified visual inspection to repetitively inspect for cracks. If cracks are found: (i) Obtain a repair scheme from the manufacturer through FAA at the address specified in paragraph (f) of this AD (ii) Incorporate this repair scheme	If type “C” damage is found, inspect for cracks prior to further flight and every 10 hours TIS thereafter. Obtain an FAA approval within 90 days or 600 takeoffs/landings, whichever occurs first, from the date of repair for type of “C” damage. An FAA approval is required to fly pressurized beyond 90 days or 600 landings/takeoffs, whichever occurs first, from date of repair for type “C damage	In accordance with Pilatus Aircraft Ltd. PC-12 Service Bulletin No. 53-003, Revision 1, dated July 26, 2002, and the applicable maintenance manual.
(5) If damage is found outside of the inspection area during the inspection required by paragraph (d)(1) of this AD, do not apply any of the repair procedures from Pilatus Aircraft Ltd. PC-12 Service Bulletin No. 53-003, Revision 1, dated July 26, 2002, to damage. If such damage is found: (i) Obtain a repair scheme from the manufacturer through FAA at the address specified in paragraph (f) of this AD (ii) Incorporate this repair scheme.	Prior to further flight after the inspection in which the damage outside the inspection area is found	Obtain this repair scheme through FAA at the address specified in paragraph (f) of this AD.

Note 1:

As earlier specified in this AD, flight is not permitted if crack damage is found.

Note 2:

As earlier specified in this AD, FAA approval is required to fly pressurized beyond 90 days or 600 takeoffs/landings, whichever occurs first, from date of repair for type “C” damage.

(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 Standards Office 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 Standards Office Manager.

Note 3:

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? Doug Rudolph, Aerospace Engineer, FAA, Small Airplane Directorate, 901 Locust, Room 301, Kansas City, Missouri 64106; telephone: [phone]; facsimile: [phone].

(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) How do I get copies of the documents referenced in this AD? You may get copies of the documents referenced in this AD Pilatus Aircraft Ltd., Customer Liaison Manager, CH-6371 Stans, Switzerland; telephone: [phone]; facsimile: [phone]; or from Pilatus Business Aircraft Ltd., Product Support Department, 11755 Airport Way, Broomfield, Colorado 80021; telephone: [phone]; facsimile: [phone]. You may view these documents at FAA, Central Region, Office of the Regional Counsel, 901 Locust, Room 506, Kansas City, Missouri 64106.

Note 4:

The subject of this AD is addressed in Swiss AD Number HB 2002-608, dated November 1, 2002.

Issued in Kansas City, Missouri, on January 8, 2003.

Dorenda D. Baker,

Acting Manager, Small Airplane Directorate, Aircraft Certification Service.