70-03-04 R1: Turbosupercharger Turbine Housing

70-03-04 R1 CESSNA: Amendment 39-933 as amended by Amendment 39-5564. Applies to the following serial numbered Models T310P, T310Q, 320D, 320E and 320F airplanes equipped with Teledyne Continental Model TSIO-520B engines, and to the following serial numbered Models 401, 401A, 401B, 402, 402A and 402B airplanes equipped with Teledyne Continental Model TSIO-520E engines: MODEL SERIAL NUMBER T310P T310P0001 thru T310P0240 T310Q T310Q0001 thru T310Q0291 320D 320D0001 thru 320D0130 320E 320E0001 thru 320E0110 320F 320F0001 thru 320F0045 401 4010001 thru 4010322 401A 401A0001 thru 401A0132 401B 401B0001 thru 401B0121 402 4020001 thru 4020322 402A 402A0001 thru 402A0129 402B 402B0001 thru 402B0122 Compliance: Within 25 hours time-in-service (TIS) after the effective date of this AD on airplanes with turbosupercharger turbine housings having 400 hours or more TIS, or at or before 425 hours TIS on turbosupercharger turbine housings having less than 400 hours TIS and thereafter at intervals not to exceed 100 hours TIS, unless already accomplished. To detect incipient failure of turbosupercharger turbine housings installed in the above airplanes, accomplish the following: (a) Remove the engine top cowling and the turbosupercharger turbine insulation blanket and visually inspect the complete surface of the turbine housing of the TCM turbosupercharger assembly P/N 632729 (AID P/N 406610) for cracks, bulges and burnt areas. Remove and reinstall the turbosupercharger insulation blanket in accordance with applicable Cessna Service Manuals. (b) If cracks, bulges or burnt areas are found during the inspection required by paragraph (a) of this AD, prior to further flight, replace the defective part with an airworthy part. (c) Replacement of the turbosupercharger turbine insulation blanket with stainless steel heat shields in accordance with Cessna Multi-engine Service Letter ME72-4, dated March 24, 1972, will terminate further time interval repetitive inspections required by this AD. However, the inspection cited in paragraph (a) above and any necessary corrective action in paragraph (b) above must be completed at the time of the heat shield installation. (d) Any equivalent method of compliance with this AD, if used, must be approved by the Manager, Wichita Aircraft Certification Office, FAA, 1801 Airport Road, Room 100, Wichita, Kansas 67209. All persons affected by this directive may obtain copies of the document(s) referred to herein upon request to Cessna Aircraft Company, Customer Services, P.O. Box 1521, Wichita, Kansas 67201; or may examine the document(s) referred to herein at the FAA, Rules Docket, Office of the Regional Counsel, Room 1558, 601 East 12th Street, Kansas City, Missouri 64106. NOTE 1: Cessna Multi-engine Service Letter No. ME70-3, dated January 9, 1970, ME70-3 Supplement I, dated February 9, 1970, and ME72-4, dated March 24, 1972, relate to this subject.NOTE 2: Time-in-service on turbosupercharger turbine housings may be determined from the engine maintenance records. This amendment revises AD 70-03-04, Amendment 39-933. This amendment becomes effective March 28, 1987.