AD 99-20-13 Airworthiness Directives; Eurocopter Canada Ltd. Model BO 105 LS A-3 Helicopters

Makes named: bendix. Read the applicability below — it usually turns on serial or part numbers too.

Model BO 105 LS A-3 helicopter, with Part Number (P/N) 2604067 (Bendix) or J17322-1 (Lord) rotor tension-torsion (TT) strap, installed, certificated in any category. Note 1: This AD applies to each helicopter identified in the preceding applicability provision, regardless of whether it has been otherwise modified, altered, or repaired in the area subject to the requirements of this AD. For helicopters 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 the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.

Required as indicated, unless accomplished previously. To prevent main rotor blade (blade) separation due to failure of a TT strap, accomplish the following: (a) Before further flight: (1) Create a component log card or equivalent record for each TT strap. (2) Review the history of the helicopter and each TT strap. Determine the age since initial installation on any helicopter (age) and the number of flights on each TT strap. Enter both the age and the number of flights for each TT strap on the component log card or equivalent record. For the time-in-service (TIS) where the number of flights is unknown, multiply the number of hours TIS by 5 to determine the number of flights. If a TT strap has been previously used at any time on a Model BO 105 LS A-3 `SUPERLIFTER', BO-105 CB- 5, BO-105 CBS-5, BO-105 DBS-5, or any MBB-BK 117 series helicopter, multiply the number of flights accumulated on those other models by a factor of 1.6 and then add that result to the number of flights accumulated on the helicopters affected by this AD. (3) Remove any TT strap from service if the total hours TIS or number of flights and age cannot be determined. (4) Remove any TT strap from service that has either accumulated 40,000 or more flights or has an age equal to or greater than 216 months. (b) When a TT strap age is greater than or equal to 120 months and less than 216 months and has accumulated less than 40,000 flights, inspect the TT strap in accordance with the ``Accomplishment Instructions,'' paragraph 2.B.2., of Eurocopter Canada Alert Service Bulletin BO 105 LS A-3 No. ASB-BO 105 LS-10-10, dated September 1, 1999 (ASB), according to the following: (1) If the age is greater than or equal to 120 months but less than 132 months and has less than 35,200 flights, inspect the TT strap within the next 6 weeks. If the number of flights equals or exceeds 35,200, inspect the TT strap before further flight. (2) If the age is greater than or equal to 132 months but less than 144 months and has less than 30,400 flights, inspect the TT strap within the next 5 weeks. If the number of flights equals or exceeds 30,400, inspect the TT strap before further flight. (3) If the age is greater than or equal to 144 months but less than 156 months and has less than 25,600 flights, inspect the TT strap within the next 4 weeks. If the number of flights equals or exceeds 25,600, inspect the TT strap before further flight. (4) If the age is greater than or equal to 156 months but less than 168 months and has less than 20,800 flights, inspect the TT strap within the next 3 weeks. If the number of flights equals or exceeds 20,800, inspect the TT strap before further flight. (5) If the age is greater than or equal to 168 months but less than 180 months and has less than 16,000 flights, inspect the TT strap within the next 2 weeks. If the number of flights equals or exceeds 16,000, inspect the TT strap before further flight. (6) If the age is greater than or equal to 180 months but less than 216 months, inspect the TT strap before further flight. (c) If a defect is found as a result of the inspections of paragraph (b), remove the TT strap from service before further flight. (d) If no defect is found as a result of the inspection, a maximum of 1,000 flights or 12 months additional time is permitted on a one-time basis before the TT strap must be replaced, provided the limits of paragraph (a)(4) are not exceeded. (e) An alternative method of compliance or adjustment of the compliance time that [[Page 56158]] provides an acceptable level of safety may be used if approved by the Manager, Regulations Group, FAA, Rotorcraft Directorate. Operators shall submit their requests through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Regulations Group, Rotorcraft Directorate. Note 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Regulations Group, Rotorcraft Directorate. (f) Special flight permits may be issued for up to five flights in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the helicopter to a location where the requirements of this AD can be accomplished. (g) The TT strap inspections shall be done in accordance with paragraph 2.B.2. of the ``Accomplishment Instructions'' in Eurocopter Canada Alert Service Bulletin BO 105 LS A-3 No. ASB-BO 105 LS-10-10, dated September 1, 1999. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from American Eurocopter Corporation, 2701 Forum Drive, Grand Prairie, Texas 75053-4005, telephone (972) 641-3460, fax (972) 641-3527. Copies may be inspected at the FAA, Office of the Regional Counsel, Southwest Region, 2601 Meacham Blvd., Room 663, Fort Worth, Texas; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. (h) This amendment becomes effective on November 2, 1999, to all persons except those persons to whom it was made immediately effective by Emergency Priority Letter AD 99-20-13, issued September 24, 1999, which contained the requirements of this amendment. Note 3: The subject of this AD is addressed in Transport Canada Civil Aviation, Canada, AD CF-99-24R1, dated September 22, 1999. Issued in Fort Worth, Texas, on October 4, 1999. Henry A. Armstrong, Manager, Rotorcraft Directorate, Aircraft Certification Service. [FR Doc. 99-26713 Filed 10-15-99; 8:45 am] BILLING CODE 4910-13-P