88-09-01 BELL HELICOPTER TEXTRON, INC.: Amendment 39-5874. Applies to Bell Helicopter Textron, Inc., Model 214ST helicopters certificated in any category. (Airworthiness Docket No. 87-ASW-64.)
Compliance is required as indicated, unless already accomplished.
(a) Within the next 25 hours' time in service after the effective date of this AD, and thereafter at intervals not to exceed 25 hours' time in service, perform an inspection of the tail rotor intermediate gearbox, P/N 214-040-009-001, as follows:
(1) Remove the fairings and covers as required to gain access to the intermediate gearbox.
(2) Visually inspect the three gearbox mounting lugs for cracks. If a crack indication is found, inspect using a fluorescent or dye penetrant method. If a crack is found, remove and replace the intermediate gearbox case with a serviceable part before further flight and accomplish the requirements of paragraphs (b)(3), (b)(5), and (b)(6) of this AD.
(3) If no cracks are found, verify that the washer stack-up is in accordance with figure 4, page 16, Section 65-20-00 of the Bell 214ST Maintenance Manual, Rev. 22, dated May 14, 1987, and determine that the torque on the three attachment bolts, P/N AN5H15A, is 100-140 in-lbs. Resecure the attachment bolts with MS20995C32 safety wire or equivalent.
(b) Within the next 250 hours' time in service after the effective date of this AD, remove and inspect the tail rotor intermediate gearbox, P/N 214-040-009-001, as follows:
(1) Remove the fairings and covers as required to gain access to the intermediate gearbox.
(2) Remove the intermediate gearbox and visually inspect the three gearbox mounting lugs for cracks. If a crack indication is found, inspect using a fluorescent or dye penetrant method. If a crack is found, remove and replace the intermediate gearbox with a serviceable part before further flight.
(3) Inspect the intermediate gearbox and intermediate gearbox support areaof the tailboom for evidence of barrier tape. If barrier tape is present, it must be removed before further flight.
(4) Inspect the intermediate gearbox mounting lugs for evidence of excessive wear and bolt hole elongation. If wear or bolt hole elongation is beyond the limits specified on pages 35 and 36 in Section 65-20-07 or figure 26, page 48, Section 65-20-08, of the Bell 214ST Component Repair and Overhaul Manual, Rev. 12, dated April 15, 1986, remove and replace the intermediate gearbox case with a serviceable part before further flight.
(5) Inspect the intermediate gearbox tailboom attachment points for excessive wear or damage. If the wear or damage is beyond the limits specified in figure 16, page 40B, Section 53-11-00 of the Bell 214ST Maintenance Manual, Rev. 22, dated May 14, 1987, remove and replace the worn or damaged parts with serviceable parts before further flight.
(6) Clean the mounting surfaces of the intermediate gearbox and tailboom using methyl-ethyl-ketone (MEK), or equivalent safety solvent. Apply epoxy polyamide primer or zinc chromate primer to the mounting surfaces. Do not use barrier tape during reassembly. Install the gearbox while the primer is wet. The washer stack-up must comply with Figure 4, page 16, Section 65-20-00 of the Bell 214ST Maintenance Manual, Rev. 22, dated May 14, 1987. Torque the three attachment bolts, P/N AN5H15A, to 100-140 in-lbs. Secure the bolts with MS20995C32 safety wire or equivalent.
(c) Upon complying with paragraph (b) of this AD, the requirements in paragraph (a) of this AD no longer apply.
(d) In accordance with FAR 21.197 and 21.199, the helicopter may be flown to a base where the requirements of this AD can be accomplished.
(e) An alternate method of compliance which provides an equivalent level of safety, may be used when approved by the Manager, Helicopter Certification Branch, Federal Aviation Administration, Fort Worth, Texas 76193-0170.
NOTE: Compliance with Parts I and II of Bell Helicopter Textron Alert Service Bulletin No. 214ST-87-40, dated 9/17/87, constitutes compliance with this AD.
The procedure shall be done in accordance with page 16, Section 65-20-00 and page 40b, Section 53-11-00 of the Bell 214ST Maintenance Manual, Rev. 22, dated May 14, 1987; and pages 35 and 36, Section 65-20-07 and page 48, Section 65-20-08 of the Bell 214ST Component Repair and Overhaul Manual, Rev. 12, dated April 15, 1986. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a)(1) and 1 CFR Part 51. Copies may be obtained from Bell Helicopter Textron, Inc., P.O. Box 482, Fort Worth, Texas 76101, Attention: Customer Support. Copies may be inspected at the Office of Regional Counsel, FAA, Southwest Region, 4400 Blue Mound Road, Fort Worth, Texas, or at the Office of the Federal Register, 1100 L Street, NW, Room 8401, Washington, D.C.
This amendment 39-5874 becomes effective April 22, 1988.