AD 2002-02-11

This amendment adopts a new airworthiness directive (AD) that applies to all Pilatus Britten-Norman Limited (Pilatus Britten-Norman) BN-2, BN-2A, BN-2B, BN-2T, and BN2A MK. III series airplanes. This AD requires you to repetitively inspect certain oleo attachment brackets for cracks and replace any cracked bracket found during any inspection. In working with the United Kingdom, we have determined that the bracket may, as an option, be replaced with a newly designed steel bracket, increasing the length of time between the repetitive inspections. The actions specified by this AD are intended to detect and correct cracked oleo attachment brackets. Such a condition could cause the attachment bracket to fail, which could result in detachment of the main landing gear.

Final rule.

2002-02-11 Pilatus Britten-Norman LTD.: Amendment 39-12639; Docket No. 2001-CE-39-AD.

(a) What airplanes are affected by this AD? This AD affects Models BN-2, BN-2A, BN-2A-2, BN-2A-3, BN-2A-6, BN-2A-8, BN-2A-9, BN-2A-20, BN-2A-21, BN-2A-26, BN-2A-27, BN-2B-20, BN-2B-21, BN-2B-26, BN-2B-27, BN-2T, BN-2T-4R, BN2A MK. III, BN2A MK. III-2, and BN2A MK. III-3 airplanes, all constructor numbers, that are certificated in any category.

(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 cracked oleo attachment brackets. Such a condition could cause the attachment bracket to fail, which could result in detachment of the main landing gear.

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

ActionsCompliance
Procedures
(1) Inspect, visually or using 10x magnifying glass, the oleo attachment brackets, part number (P/N) NB-40-0075, for cracks.
Within the next 25 hours time-in-service (TIS) or 50 landings, whichever occurs first, after March 25, 2002 (the effective date of this AD), and thereafter at intervals not to exceed 500 hours TIS or 1200 landings, whichever occurs first.
In accordance with B-N Service Bulletin Number SB 273, Issue 3 dated December 5, 2001, and the applicable maintenance manual.
(2) Inspect visually or using 10x magnifying glass, the oleo attachment brackets, P/N NB-40-0479, for cracks.
Within the next 4 years after the date of installation or the next time the main landing gear is removed, whichever occurs first, after March 25, 2002 (the effective date of this AD), and repetitively inspect thereafter every time the main landing gear is removed or at intervals not to exceed 4 years, whichever occurs first.
In accordance with B-N Service BulletinNumber SB 273, Issue 3, dated December 5, 2001, and the applicable maintenance manual.
(3) If cracks are found during any inspection required in paragraph (d)(1) or (d)(2) of this AD, replace the cracked oleo attachment bracket with another oleo attachment bracket, P/N NB-40-0075 or P/N NB-40-0479.
Prior to further fight after the inspection(s) required in paragraph (d)(1) and (d)(2) of this AD in which the crack is found. Repetitively inspect at the repetitive inspection intervals specified in paragraph (d)(1) or (d)(2) of this AD, whichever is applicable.
In accordance with B-N Service Bulletin Number SB 273, Issue 3, dated December 5, 2001, and the applicable maintenance manual.
(4) Do not install any oleo attachment bracket, P/N NB-40-0075 or NB-40-0479 (or FAA-approved equivalent part number), unless it has been inspected as required in paragraph (d)(1) and (d)(2) of this AD and determined to be airworthy.
As of March 25, 2002 (the effective date of this AD.

Not applicable.

(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 B-N Service Bulletin Number SB 273, Issue 3, dated December 5, 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 Britten-Norman Limited, Bembridge, Isle of Wight, United Kingdom PO35 5PR. 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.

Note 2: The subject of this AD is addressed in United Kingdom CAA AD 005-09-2000, not dated.

(i) When does this amendment become effective? This amendment becomes effective on March 25, 2002.

Discussion

What Events Have Caused This AD?

The Civil Aviation Authority (CAA), which is the airworthiness authority for the United Kingdom, notified FAA that an unsafe condition may exist on all BN-2, BN-2A, BN-2B, BN-2T, and BN2A MK. III series airplanes. The United Kingdom CAA reports five occurrences of failure of the oleo attachment bracket, part number (P/N) NB-40-0075. This bracket is the main attachment point for the main landing gear. The CAA determined that the cause for failure of these brackets is the current design of P/N NB-40-0075.

What Is the Potential Impact If FAA Took No Action?

Cracked oleo attachment brackets, if not detected and corrected, could fail and detach from the main landing gear.

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 Britten-Norman BN-2, BN-2A, BN-2B, BN-2T,and BN2A MK. III series airplanes. This proposal was published in the Federal Register as a notice of proposed rulemaking (NPRM) on November 23, 2001 (66 FR 58687). The NPRM proposed to require you to repetitively inspect the oleo attachment brackets, P/N NB-40-0075, for cracks and replace any cracked bracket found during any inspection. Accomplishment of the proposed actions as specified in the NPRM would be required in accordance with B-N Service Bulletin Number 273, Issue 2, dated January 12, 2000.

Is There a Modification I Can Incorporate Instead of Repetitively Inspecting the Oleo Attachment Brackets?

The FAA has determined that long-term continued operational safety would be better assured by design changes that remove the source of the problem rather than by repetitive inspections or other special procedures.

The manufacturer has changed the design of the oleo attachment bracket, P/N NB-40-0075, which is made of aluminum alloy. The newly designed oleo attachment bracket, P/N NB-40-0479, is made of steel. This design reduces the number of repetitive inspections. The newly designed part has been introduced in Issue 3 of B-N Service Bulletin Number SB 273.

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.

We did receive Issue 3 of B-N Service Bulletin Number SB 273. This service bulletin introduces the new design oleo attachment bracket described above. We have determined that the option to install this new design bracket should be incorporated into the AD. This installation will increase the time between repetitive inspection intervals (reduce the number of inspections).

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 126 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 inspections:

Labor cost
Parts cost
Total cost per airplane
Total cost on U.S. operators
3 workhours x $60 per hour = $180.
No cost for parts
$180
$180 x 126 = $22,680

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

Labor cost
Parts cost
Total cost per airplane
12 workhours x $60 per hour = $720.
$370
$720 + $370 = $1,090

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 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: