AD 81-13-11

81-13-11 COSTRUZIONI AERONAUTICHE GIOVANNI AGUSTA: Amendment 39- 4142. Applies to Model A109A series helicopters, certificated in all categories, that have main rotor blades, P/N 1090-0103-01-07, installed.

Compliance required as indicated, unless already accomplished.

To detect and prevent corrosion which could result in an in-flight rotor blade failure, accomplish the following:

(a) Within the next 25 hours time in service after the effective date of this AD:

(1) Inspect the main rotor blade leading edge abrasion strip inner end and scarf joint for filler erosion, filler release, and corrosion, in accordance with Part I of the "Accomplishment" paragraph of Agusta Bollettino Tecnico No. 109-7, dated February 6, 1978, or an FAA-approved equivalent.

(2) If no filler erosion or release is found during the inspection specified in paragraph (a)(1) of this AD, apply a polyurethane tape to the blade and comply with paragraph (b) of this AD.

(3) If fillererosion or release is found during the inspection specified in paragraph (a)(1) of this AD, clean the area and inspect for corrosion and bond separation.

(4) If corrosion or bond separation is not found during the inspection in paragraph (a)(3) of this AD, fill with urethane adhesive, apply a polyurethane tape to the blade, and comply with paragraph (b) of this AD.

(5) If corrosion is not found during the inspection required by paragraph (a)(3) of this AD but marginal bonding separation not deeper than 5 mm. (0.2 in.) is found, clean and flush the area, fill with urethane adhesive, apply a polyurethane tape to the blade, and comply with paragraph (b) of this AD.

(6) If corrosion or bond separation deeper than 5 mm. (0.2 in.) is found during the inspection required by paragraph (a)(3) of this AD, replace the blade with a serviceable blade of the same part number, or an FAA-approved equivalent, return the helicopter to service and comply with paragraph (b) of this AD.(b) After the last flight of each day in which the helicopter is operated after compliance with paragraph (a) of this AD, check the main rotor blade polyurethane tapes for condition and adhesion in accordance with Part II of the "Accomplishment" paragraph of Agusta Bollettino Tecnico No. 109-7, dated February 6, 1978, or an FAA-approved equivalent. The check required by this paragraph may be accomplished by the pilot.

(c) If during the check required by paragraph (b) of this AD, a tape defect or abnormal condition including bond separation is found, comply with paragraph (a) of this AD before flight, except that the helicopter may be flown in accordance with FAR Sections 21.197 and 21.199 to a base where the work can be performed.

(d) If an equivalent means of compliance is used in complying with this AD, that equivalent must be approved by the Chief, Aircraft Certification Staff, AEU-100, FAA, Europe, Africa and Middle East Office, c/o American Embassy, Brussels, Belgium.

The manufacturer's specifications and procedures identified and described in this directive are incorporated herein and made a part hereof pursuant to 5 U.S.C. 552(a)(1). All persons affected by this directive who have not already received these documents from the manufacturer may obtain copies upon request to Costruzioni Aeronautiche Giovanni Agusta, Cascina Costa (Gallarate), Italy. These documents may be examined at FAA Headquarters, Room 916, 800 Independence Avenue, SW., Washington, DC 20591.

This amendment becomes effective July 20, 1981.