AD 2008-02-19 Airworthiness Directives; Honeywell International Inc. TFE731-2C, -3B, -3BR, -3C, -3CR, -3D, -3DR, -4R, -5AR, -5BR, -5R, -20R, -20AR, -20BR, -40, -40AR, -40R, and -60 Series Turbofan Engines

This AD applies to Honeywell International Inc. (Honeywell) TFE731-2C, -3B, -3BR, -3C, -3CR, -3D, -3DR, -4R, -5AR, -5BR, -5R, -20R, -20AR, -20BR, -40, -40AR, -40R, and -60 series turbofan engines with certain high pressure (HP) turbine rotor discs part numbers and serial numbers. These engines are installed on, but not limited to, the following airplanes:     Avions Marcel Dassault Mystere-Falcon 10 and 50 Series Cessna Model 650; Citations III, VI, and VII Dassault-Aviation 20, 50, 50EX, 900, MF900, and 900EX (900DX) Series Gulfstream Aerospace LP (formerly IAI) 1125 Westwind Astra, Astra SPX, Gulfstream 100 Series Israel Aircraft Industries (IAI) 1124 Series (Westwind 1124) Learjet 31, 35, 36, 45 (or Learjet 40), and 55 Series Lockheed-Georgia 3329-25 Series (731 Jetstar, Jetstar II) Raytheon Corporate Jets (formerly British Aerospace) Hawker 800 and 850 Series Sabreliner NA-265-65 (Sabreliner 65)

You are responsible for having the actions required by this AD performed within the compliance times specified unless the actions have already been done. TFE731-2C, -3B, -3BR, -3C, -3CR, -3D, -3DR, -4R, -5AR, -5BR, and -5R Series Turbofan Engines (f) For TFE731-2C, -3B, -3BR, -3C, -3CR, -3D, -3DR, -4R, -5AR, -5BR, and -5R series turbofan engines, remove HP turbine rotor assemblies from service containing HP turbine rotor discs, part number (P/N) 3075772-1, having any serial number (SN) in Table 1 of Honeywell Service Bulletin (SB) No. TFE731-72-3720, dated July 5, 2006. Use the following drawdown schedule: (1) For HP turbine discs with 4,200 cycles-since-new (CSN) or more on the effective date of this AD, remove HP turbine rotor assemblies within 100 cycles-in-service (CIS) after the effective date of this AD. (2) For HP turbine discs with fewer than 4,200 CSN on the effective date of this AD, remove HP turbine rotor assemblies at the next access to the HP turbine rotor discs, but not to exceed 4,300 CSN. TFE731-20R, -20AR, -20BR, -40, -40AR, -40R, and -60 Series Turbofan Engines (g) For TFE731-20R, -20AR, -20BR, -40, -40AR, -40R, and -60 series turbofan engines, remove HP turbine rotor assemblies from service containing HP turbine rotor discs, P/N 3060841-1, having any SN in Table 1 of Honeywell Alert SB No. TFE731-A72-5185, dated July 5, 2006. Use the following drawdown schedule: (1) For HP turbine discs with 3,200 CSN or more on the effective date of this AD, remove HP turbine rotor assemblies within 100 CIS after the effective date of this AD. (2) For HP turbine discs with fewer than 3,200 CSN on the effective date of this AD, remove HP turbine rotor assemblies at the next access to the turbine rotor discs, but not to exceed 3,300 CSN. For All Engines (h) HP turbine rotor discs removed per paragraphs (f) and (g) of this AD must pass a curvic root radius inspection performed by Honeywell Engines, Systems and Services, Phoenix, Arizona, Certificate Repair Station No. ZN3R030M, before the discs are eligible for reinstallation in an engine. (i) For the purposes of this AD, access to the HP turbine rotor discs is defined as the removal of the HP turbine rotor assembly from the engine. Alternative Methods of

This AD results from the manufacturer's report that some HP turbine rotor discs received improperly machined radii in the root of the forward and aft curvic teeth during manufacture. We are issuing this AD to prevent uncontained failure of the HP turbine rotor assembly, which could result in damage to the airplane.