AD 75-16-20

75-16-20 MITSUBISHI HEAVY INDUSTRIES, LIMITED: Amendment 39-2294. Applies to Mitsubishi Model MU-2B, MU-2B-10, MU-2B-15, MU-2B-20, MU-2B-25, MU-2B- 26, MU-2B-30, MU-2B-35, and MU-2B-36 airplanes certificated in all categories. Compliance is required within the next 25 hours time in service after the effective date of this AD, unless already accomplished within the last 75 hours time in service, and thereafter at intervals not to exceed 100 hours time in service from the last inspection. To prevent possible separation of the control lever on the engine propeller pitch control unit, inspect the propeller pitch control lever, Mitsubishi P/N 022A-43111, P/N 022A-43111-3, or P/N 867304-1 in accordance with paragraph (a) or (b) of this AD, as applicable. (a) For airplanes with AN3H5A bolt or MS24673-3 bolt installed in a threaded propeller pitch control lever, accomplish the following: (1) Remove safety wire and loosen bolt. (2) Ensure that the propeller pitch control leveris mounted securely on the shaft. (3) Retorque the AN 3H5A bolt to 20-25 inch pounds or the MS24673-3 bolt to 25-30 inch pounds, as applicable, and install safety wire. (4) Ensure that the power management system is properly rigged in accordance with Section VI of the Garrett-Airesearch Turboprop Engine Series 331 Maintenance Manual or an FAA-approved equivalent. (b) For airplanes with AN3-6A bolt and NAS679C3W nut installed in an unthreaded propeller pitch control lever, accomplish the following: (1) Loosen the AN3-6A bolt. (2) Ensure that the propeller pitch control lever is mounted securely on the shaft. (3) Retorque the AN3-6A bolt to 20-25 inch pounds. (4) Ensure that the power management system is properly rigged in accordance with Section VI of the Garrett-Airesearch Turboprop Engine Series 331 Maintenance Manual or an FAA-approved equivalent. (Mitsubishi MU-2 Service Bulletin No. 168, dated April 18, 1975, refers to this same subject). This amendment becomes effective August 12, 1975.