AD/HU 369/37 - Tail Rotor Swashplate Bearing Locknut - Inspection and Increase in Torque (Cth)

COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES

McDonnell Douglas (Hughes) and Kawasaki 369 Series Helicopters

AD/HU 369/37 Tail Rotor Swashplate Bearing Locknut - Inspection and Increase in Torque

6/79

Applicability: All model 369D with S/Nos. from 0003D to 0409D, not modified in accordance with Hughes SIN DN-37.

Requirement: 1. Visually inspect the tail rotor swashplate bearing as follows;

(a) Pull back the non-rotating boot P/N 369D21806 from the tail rotor pitch control assembly P/N 369D21800 and check the locknut and tang washer by hand for looseness.

(b) If the locknut or tang washer is loose, remove and replace the tail rotor pitch control assembly with a serviceable assembly with a white dot on the locknut, before further flight.

2. Modify the tail rotor swashplate in accordance with Hughes SIN DN-37. For aircraft maintained in accordance with ANO 100.5.1, Part 1 of this Directive shall be entered on the maintenance release as maintenance required. The inspection may be performed by the pilot in command, in which case certification is not required. In all other cases certification may be made on the maintenance release. This inspection may also be performed and certified by any Licensed Aircraft Maintenance Engineer.

Compliance: For Part 1 - At each preflight inspection, until modified in accordance with Part 2.

For Part 2 - Within 100 hours time in service after 10 May 1979.

Background: To prevent loosening of the tail rotor swashplate bearing locknut and possible loss of tail rotor control, the tightening torque of the locknut is increased. Until this is accomplished, the locknut is to be inspected prior to each flight.