2001-09-11 Bell Helicopter Textron, Inc. and Agusta S.p.A.: Amendment 39-12217. Docket No. 99-SW-27-AD. Supersedes AD 98-07-03, Amendment 39-10421, Docket No. 97-SW-58-AD.
Applicability: Bell Helicopter Textron, Inc. Model 412, 412CF, and 412EP helicopters and Agusta S.p.A. Model AB412 helicopters, with tail rotor yoke assembly, part number (P/N) 212-011-702-all dash numbers, 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.
Compliance: Required as indicated, unless accomplished previously.
To prevent static and dynamic overload damage to the tail rotor yoke (yoke) that could result in loss of the tail rotor and subsequent loss of control of the helicopter, accomplish the following:
(a) Before further flight, review the historical records of the yoke assembly for any static or dynamic overload damage that could have imposed a bending load on the yoke. The damage may not have required replacing the yoke assembly; for example, an incident in which a damaged tail rotor blade was replaced due to a blade strike. If the records indicate that overload damage may have occurred, replace the yoke with an airworthy yoke.
(b) Before further flight, unless the requirements of paragraph (c) of this AD have been accomplished previously:
(1) Install a Never Exceed Velocity (Vne) red line at 120 knots indicated airspeed (KIAS) on the pilot and copilot airspeed indicators using red tape or paint and a slippage indicator on the instrument case and glass.
(2) Install a placard made of material that is not easily erased, disfigured, or obscured on the instrument panel in clear view of the pilot and copilot:
"Observe temporary Maximum Never Exceed (Vne) airspeed red line (marked at 120 knots indicated airspeed (KIAS)). Vne is 20 KIAS less than the value presented on the airspeed limitation placard for each ambient condition."
(3) Insert the applicable Bell Helicopter Textron (BHT) 412 Temporary Revision, dated August 16, 1996, into the Model 412 Rotorcraft Flight Manual (RFM) or the applicable section of Agusta AB412 Temporary Revision No. 2, dated April 17, 1997, into the Model AB412 RFM.
(c) Within 180 calendar days:
(1) Remove yoke assembly, P/N 212-011-702-all dash numbers, andreplace it with an airworthy yoke assembly, P/N 212-011-702-all dash numbers, with zero hours time-in-service (TIS), or an airworthy yoke (regardless of TIS) that has passed a one-time x-ray diffraction inspection in accordance with BHT Alert Service Bulletin (ASB) 412-96-89, Revision A, dated October 17, 1997; BHT ASB 412CF-96-01, dated September 3, 1996; or Agusta Bolletino Tecnico (Technical Bulletin) No. 412-65, dated April 17, 1997, whichever is applicable.
(2) Install an airworthy tail rotor flapping stop, P/N 212-011-713-103.
(3) After the requirements of paragraphs (c)(1) and (c)(2) of this AD are accomplished, remove the 120 KIAS redline from the pilot and copilot airspeed indicators; remove the Vne airspeed restriction placard; and remove the BHT 412 Temporary Revision, dated August 16, 1996; BHT ASB 412CF-96-01, dated September 3, 1996; or Agusta AB412 Temporary Revision No. 2, as applicable, from the RFM.
(d) After accomplishing the requirements of paragraph (c) of this AD, at intervals not to exceed 25 hours TIS, inspect the yoke assembly and tail rotor flapping stop (stop) in accordance with Part III, Recurring 25-Hour Special Inspection and Conditional Inspection Requirement, of BHT ASB 412-96-89, Revision A, dated October 17, 1997; BHT ASB 412CF-96-01, dated September 3, 1996; or Agusta Technical Bulletin No. 412-65, dated April 17, 1997, as applicable. Replace any unairworthy yoke assembly or stop with an airworthy yoke assembly or stop before further flight.
(e) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Regulations Group, Rotorcraft Directorate, FAA. 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.
Note 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Regulations Group.
(f) Special flight permits may be issued in accordance with Secs. 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the helicopter at airspeeds not to exceed 120 KIAS to a location where the requirements of this AD can be accomplished.
(g) The inspections and installations shall be done in accordance with Bell Helicopter Textron Alert Service Bulletin 412-96-89, Revision A, dated October 17, 1997; Bell Helicopter Textron Alert Service Bulletin 412CF-96-01, dated September 3, 1996; or Agusta Bolletino Tecnico (Technical Bulletin) No. 412-65, dated April 17, 1997. The incorporation by reference of those documents was approved previously by the Director of the Federal Register, in accordance with 5 U.S.C. 552(a) and 1 CFR part 51, as of April 8, 1998 (63 FR 14026, March 24, 1998), as corrected on July 20, 1998 (63 FR 38742). Copies may be obtained from Bell Helicopter Textron, Inc., P.O. Box 482, Fort Worth, Texas 76101, telephone (817) 280-3391, fax (817) 280-6466; or Agusta, 21017 Cascina Costa di Samarate (VA), Via Giovanni Agusta 520, telephone (0331) 229111, fax (0331) 229605-222595. 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 June 11, 2001.
Note 3: The subject of this AD is addressed in Registro Aeronautico Italiano (Italy) AD 97-223, dated August 1, 1997.