AD 2001-03-11

This amendment adopts a new airworthiness directive (AD) that applies to all British Aerospace HP137 Mk1, Jetstream series 200, and Jetstream Models 3101 and 3201 airplanes that are equipped with certain main landing gear (MLG) radius rods. This AD requires inspection of the MLG radius rods for cracks and replacement of any cracked rod. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for the United Kingdom. The actions specified by this AD are intended to detect and correct cracks in the MLG radius rods. Such cracks could result in MLG failure during takeoff, landing, or taxi operations, with consequent loss of airplane control.

Final rule

2001-03-11 BRITISH AEROSPACE: Amendment 39-12115; Docket No. 2000-CE-54-AD.

(a) What airplanes are affected by this AD? This AD affects HP137 Mk1, Jetstream series 200, and Jetstream Models 3101 and 3201 airplanes, all serial numbers, that are:

(1) certificated in any category; and

(2) equipped with a main landing gear (MLG) radius rod, APPH Ltd. part number 1847 or 1862, all suffixes.

(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 detect and correct cracks in the MLG radius rods. Such cracks could result in MLG failure during takeoff, landing, or taxi operations, 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) Check the maintenance records to determine whether one of the affected MMLG radius rods is installed.

(2) If, by checking the maintenance
records, you can positively show that one of the affected MLG radius rods is not installed, then the inspection and possible replacement requirements of this AD do not apply. Make an entry into the aircraft record that shows compliance with this portion of the AD, in accordance with section 43.9 of the Federal Aviation Regulations (14 CFT 43.9).

(3) If, by checking the maintenance
records, you find that one of the affected MLG radius rods is installed or you cannot positively show that one of the affected MLG radius roads is not installed, inspect any affected MLG radius rod for cracks.

(4) If any MLG radius road is found cracked, replace it with an FAA-approved MLG radius rod that is crack free.

(5) Do not install, on any affected airplane, a part number 1847 or 1862 MLG radius road (all suffixes), unless it has been inspected and is found to be free of cracks as specified in paragraph (d) (3).

(6) The owner/operator holding at least a private pilot certificate as authorized by section 43.7 of the Federal Aviation Regulations (14 CFT 43.7) may accomplish the actions required in paragraphs (d) (1) and (d) (2) of this AD.
Within the next 200 hours
time-in-service (TIS) after
April 6, 2001 (the effective
Date of this AD), unless already accomplished.

Prior to further flight after
checking the maintenance records

Prior to further flight after checking the maintenance records, unless already accomplished.

Prior to further flight after the inspection.

As of April 6, 100` (the effective date of this AD).

Not Applicable.
As specified in British
Aerospace Mandatory Service
Bulletin 32-JA 991140, Issued:
April 14, 2000.

Not Applicable.

In accordance with the
procedures in APPH Ltd.
Service Bulletin 1847-32-07,
dated February 2000; or APPH
Ltd. Service Bulletin 1862-32-07
dated February 2000, as
applicable.

In accordance with the
procedures in the applicable
maintenance manual.

Not Applicable.

Not Applicable.

Note 1: British Aerospace Mandatory Service Bulletin 32-JA 991140, Issued: April 14, 2000; APPH Ltd. Service Bulletin 1847-32-07, dated February 2000; and APPH Ltd. Service Bulletin 1862-32-07, dated February 2000, state if no cracks are found during the inspection required in paragraph (d) (3), check the edge of the one-way restrictor bore and radius sharp edge with a 0.010 to 0.020 inch radius if required. The FAA highly recommends that this be accomplished.

Note 2: British Aerospace Mandatory Service Bulletin 32-JA 991140, Issued: April 14, 2000; APPH Ltd. Service Bulletin 1847-32-07, dated February 2000; and APPH Ltd. Service Bulletin 1862-32-07, dated February 2000, specify reporting the results of the inspections to British Aerospace Regional Aircraft. The FAA highly recommends that each owner/operator submit this information. British Aerospace and the British Civil Airworthiness Authority (CAA) will use this information to determine whether further action is necessary. The FAA will evaluate the information from the British CAA and may initiate further rulemaking action.

(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 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. Forairplanes 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 Mr. 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 British Aerospace Mandatory Service Bulletin 32-JA 991140, Issued: April 14, 2000, APPH Ltd. Service Bulletin 1847-32-07, dated February 2000, and APPH Ltd. Service Bulletin 1862-32-07, dated February 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 British Aerospace Regional Aircraft, Prestwick International Airport, Ayrshire, KA9 2RW, Scotland. 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 effectiveon April 6, 2001.

Note 4: The subject of this AD is addressed in British AD 002-04-2000, not dated.

Discussion
What events have caused this AD? The Civil Aviation Authority (CAA), which is the airworthiness authority for the United Kingdom, recently notified the FAA that an unsafe condition may exist on certain British Aerospace HP137 Mk1, Jetstream series 200, and Jetstream Models 3101 and 3201 airplanes. The CAA reports an incident where a MLG radius rod cylinder cracked, which allowed the gland nut to separate from the housing and caused the MLG unit to move 30 degrees outboard.

The cause has been traced to a quality control problem with the MLG manufacturer, APPH Ltd. In particular, the cause is inadequate countersinking of a drilled hole for the attachment of a flexible hose on a batch of MLG radius rods, part numbers 1847 and 1862, all suffixes.

What are the consequences if the condition is not corrected? Cracks in the MLG radius rods, if not detected and corrected, could result in MLG failure during takeoff, landing, or taxi operations, with consequent loss of airplane control.

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 British Aerospace HP137 Mk1, Jetstream series 200, and Jetstream Models 3101 and 3201 airplanes that are equipped with certain main landing gear (MLG) radius rods. This proposal was published in the Federal Register as a notice of proposed rulemaking (NPRM) on November 2, 2000 (65 FR 65800). The NPRM proposed to require inspection of the MLG radius rods for cracks, with replacement of any cracked rod.

Was the public invited to comment? Interested persons were afforded an opportunity to participate in the making of this amendment. No comments were 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 264 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
10 workhours X $60
per hour = $600
No parts required for
inspection
$600 per airplane
$600 x 264 =
$158,400

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

Labor Cost
Parts Cost
Total Cost Per Airplane
2 workhours X $60 per hour =
$120 to accomplish each MLG
radius rod replacement
. $7,315 per MLG radius rod

$120 + $7,315 = $7,435 per MLG
radius rod that needs replaced.

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 RegulatoryPolicies 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.

39.13 [Amended]
2. FAA amends 39.13 by adding a newAD to read as follows: