AD 98-07-10 Airworthiness Directives; Agusta S.p.A. Model AB 412 Helicopters

Models named: AB 412. Read the applicability below — it usually turns on serial or part numbers too.

Agusta Model AB 412 helicopters with tail rotor blades, part number (P/N) 212-010-750-105, serial number (S/N) A5- (all 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 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 use the authority provided in paragraph (b) to request approval from the FAA. This approval may address either no action, if the current configuration eliminates the unsafe condition, or different actions necessary to address the unsafe condition described in this AD. Such a request should include an assessment of the effect of the changed configuration on the unsafe condition addressed by this AD. In no case does the presence of any modification, alteration, or repair remove any helicopter from the applicability of this AD.

Required within 10 hours time-in-service, unless accomplished previously. To prevent increased vibration levels, damage to the tail rotor drive system or tail rotor assembly, and subsequent loss of control of the helicopter, accomplish the following: (a) Inspect tail rotor blades for debond voids in accordance with the Accomplishment Instructions of Agusta Bollettino Tecnico (Technical Bulletin) No. 412-66, dated June 27, 1997 (hereafter referred to as ``Technical Bulletin''). (1) If a debond void is detected which does not exceed the limits prescribed in paragraph 3 of the Technical Bulletin, repair the tail rotor blade (blade) or replace it with an airworthy blade. (2) If a debond void exceeds the limits prescribed in paragraph 3 of the Technical Bulletin, replace the blade with an airworthy blade. (b) 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, Rotorcraft Standards Staff, 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, Rotorcraft Standards Staff. Note 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Rotorcraft Standards Staff. (c) Special flight permits will not be issued. (d) The inspection shall be done in accordance with Agusta Technical Bulletin No. 412-66, dated June 27, 1997. 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 Agusta S.p.A., 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. (e) This amendment becomes effective on April 16, 1998. Note 3: The subject of this AD is addressed in Registro Aeronautico Italiano (Italy) AD 97-194, dated July 9, 1997. Issued in Fort Worth, Texas, on March 24, 1998. Eric Bries, Acting Manager, Rotorcraft Directorate, Aircraft Certification Service. [FR Doc. 98-8464 Filed 3-31-98; 8:45 am] BILLING CODE 4910-13-U