AD 2001-05-02

This amendment supersedes Airworthiness Directive (AD) 98-08-22, which currently requires inspecting the elevator and rudder attachment brackets for cracks and corrosion on certain Pilatus Aircraft Ltd. (Pilatus) Model PC-7 airplanes and replacing any cracked or corrosion-damaged parts . Since the issuance of AD 98-08-22, Pilatus has redesigned the brackets. Installation of these brackets should inhibit corrosion, which resulted in cracks or corrosion damage. This AD requires you to replace the elevator and rudder attachment brackets with parts of improved design. 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 failure of the elevator and rudder attachment brackets because of cracks or corrosion damage. Such failure could result in the elevator or rudder separating from the airplane with consequent loss of airplane control.

Final rule

2001-05-02 PILATUS AIRCRAFT LTD: Amendment 39-12138; Docket No. 2000-CE-46-AD; Supersedes AD 98-08-22, Amendment 39-10471.

(a) What airplanes are affected by this AD? This AD affects Model PC-7 airplanes, serial numbers MSN 001 through MSN 612, 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 failure of the elevator and rudder attachment brackets because of cracks or corrosion damage, which could result in the elevator or rudder separating from the airplane with consequent loss of airplane control.

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

Actions
Compliance
Procedures
(1) Replace the horizontal
stabilizer brackets with new parts
using replacement kit No.
500.50.07.132 and replace the
vertical stabilizer bracket with new
parts using replacement kit No.
500.50.07.133.
Within the next 100 hours
time-in-service (TIS) or 6
months after April 27, 2001
(the effective date of this AD),
whichever occurs first, unless
already accomplished
.
In accordance with the
Accomplishment Instructions
of Pilatus Service Bulletin No.
55-005, dated March 23, 2000,
the aircraft maintenance
manuals, and illustrated parts
catalogs
(2) Do not install any parts
identified as old parts in
replacement kit No. 500.50.07.132
(or FAA-approved equivalent part
numbers) or 500.50.07.133 (or
FAA-approved equivalent part
number).
As of April 27, 2001 (the
effective date of this AD).

Not Applicable.

(e) Can I comply with this AD in any other way?

(1) You may use an alternative method of compliance or adjust the compliance time if:

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

(ii) 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.

(2) Alternative methods of compliance approved under AD 98-08-22, which is superseded by this AD, are not approved as alternative methods of compliance with this AD.

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 Roman Gabrys, Aerospace Engineer, FAA, Small Airplane Directorate, 901 Locust, Room 301, Kansas City, Missouri 64106; telephone: (816) 329-4141; 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. 55-005, dated March 23, 2000. 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. 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) Does this AD action affect any existing AD actions? This amendment supersedes AD 98-08- 22, Amendment 39-10471.

(j) When does this amendment become effective? This amendment becomes effective on April 27, 2001.

Note 2: The subject of this AD is addressed in Swiss AD HB 2000-411, dated September 27, 2000.

Discussion
Has FAA taken any action to this point? Reports received from the Federal Office for Civil Aviation (FOCA), which is the airworthiness authority for Switzerland, revealed instances of corrosion and cracking in the elevator and rudder attachment brackets on Pilatus Model PC-7 airplanes that have been operated in areas of high humidity or salt content. This caused FAA to issue AD 98-08-22, Amendment 39-10471 (63 FR 19175, April 17, 1998). That AD requires you to inspect the elevator and rudder attachment brackets for cracks and/or corrosion, and replace any cracked or corrosion-damaged parts, as applicable.

What has happened since AD 98-08-22 to initiate this action? The FOCA recently notified FAA of the need to change AD 98-08-22. The FOCA reports that Pilatus has redesigned the elevator and rudder attachment brackets. Installation of these brackets should inhibit the cause of corrosion, which resulted in cracks or corrosion damage.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 January 2, 2001 (66 FR 57). The NPRM proposed to supersede AD 98-08-22. AD 98-08-22 currently requires inspecting the elevator and rudder attachment brackets for cracks and corrosion, and replacing any cracked or corrosion-damaged parts. Since the issuance of AD 98-08-22, Pilatus has redesigned the brackets. Installation of these brackets should inhibit corrosion, which resulted in cracks or corrosion damage. The NPRM also proposed to require you to replace the elevator and rudder attachment brackets with parts of improved design.

Was the public invited to comment? Interested persons were afforded an opportunity to participate in the making of this amendment. No commentswere received on the proposed rule or the FAA's 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 determined that these minor corrections:

- will not change the meaning of the AD; and
- will not add any additional burden upon the public than was already proposed.

Cost Impact
How many airplanes does this AD impact? We estimate that this AD affects 8 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 modification:

Labor Cost
Parts Cost
Total Cost Per Airplane
Total Cost on U.S
Operators.

8 workhours X $60 per hour = $480
Parts will be provided by the manufacturer free of charge
$480
$480 X 8 = $3,840

Why is the compliance in hours time-in-service (TIS) and calendar time? The affected airplanes are used in general aviation operations. Some operators may accumulate 100 hours TIS on the airplane in less than 6 months. We have determined that the dual compliance time:

- gives all owners/operators of the affected airplanes adequate time to schedule and do the actions in this AD; and

- ensures that the unsafe condition referenced in this AD will be corrected within a reasonable time period without inadvertently grounding any of the affected airplanes.

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 the States, or on the distribution of power and responsibilities among the various levels of government. Therefore, it is determined that thisfinal 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, theFederal 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.

39.13 [Amended]
2. FAA amends 39.13 by removing Airworthiness Directive (AD) 98-08-22, Amendment 39- 10471 (63 FR 19175, April 17, 1998), and by adding a new AD to read as follows: