78-17-03 BELL HELICOPTER TEXTRON (BHT): Amendment 39-3282 as amended by Amendment 39-3359 (Airworthiness Docket No. 78-ASW-37). Applies to Model 212 helicopters certificated in all categories equipped with main transmission spiral bevel gear, P/N 204-040-701-3.
Compliance is required as indicated.
To minimize the possibility of failure of the input spiral bevel gear, P/N 204-040-701-3, used in the main transmission of Bell Helicopter Textron (BHT) Model 212 helicopters, accomplish the following:
a. Within the next 25 hours time in service after the effective date of this Airworthiness Directive (AD):
1. For helicopters with rotor brakes, remove the rotor brake quill assembly, P/N 205-040-300-1, as prescribed by paragraph 1 of Part I of BHT Service Bulletin No. 212-78-8, dated July 28, 1978, or later FAA approved revision.
2. For helicopters without rotor brakes, remove the cover plate, P/N 204-040-174-1, from the left side of the transmission.
3. Utilizing the opening provided by step 1 or step 2, above, inspect all 62 teeth of the main spiral bevel gear, P/N 204-040-701-3, as prescribed by paragraph 2 of Part I of BHT Service Bulletin No. 212-78-8, dated July 28, 1978, or later FAA approved revision.
4. Remove and replace any gear that does not meet the inspection requirements set forth in step 3, above. Utilize instructions in the appropriate maintenance and overhaul manual for this procedure.
5. Install cover, P/N 204-040-174-1, over rotor brake quill port, reinstall panels and cowling, and perform the ground run utilizing procedures prescribed by paragraphs 4, 5, and 6 of Part I of BHT Service Bulletin No. 212-78-8, dated July 28, 1978, or later FAA approved revision.
6. Install adjacent to the limitation placard on the rotor brake handle in the crew compartment a decal or placard with the following words: ROTOR BRAKE INOPERATIVE. Letters are to be 1/8-inch minimum height printed or embossed on a contrasting background.
b. Within 25 hours time in service after accomplishment of the requirements of paragraph a. of this AD, and thereafter at intervals not to exceed 25 hours time in service, conduct the inspections and replacement, if appropriate, prescribed by Part II of BHT Service Bulletin No. 212-78-8, dated July 28, 1978, or later FAA approved revision.
BHT Service Bulletin No. 212-78-8 pertains to and provides for accomplishing the intent of this AD except that in addition, paragraph a, step 6, of this AD must also be accomplished. BHT Service Bulletin No. 212-78-12 also provides instructions and details pertinent to this AD.
Except as specifically provided otherwise by this AD, the manufacturer's specifications and procedures identified and described in this directive are incorporated herein and made a part thereof pursuant to 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 the Service Manager, Bell Helicopter Textron, Post Office Box 482, Fort Worth, Texas 76101. These documents may also be examined at the Office of the Regional Counsel, Southwest Region, Federal Aviation Administration, 4400 Blue Mound Road, Fort Worth, Texas 76106, and at the Federal Aviation Administration Headquarters, 800 Independence Avenue, S.W., Washington, D.C. 20591.
Equivalent means of compliance with the requirements prescribed by this AD may be approved by the Chief, Engineering and Manufacturing Branch, Flight Standards Division, Southwest Region, Federal Aviation Administration, Post Office Box 1689, Fort Worth, Texas 76101.
Amendment 39-3282 became effective August 21, 1978.
This amendment 39-3359 becomes effective November 22, 1978.