Summary
We propose to adopt a new airworthiness directive (AD) for certain Honeywell International Inc. models TFE731-4, -4R, -5, -5R, - 5AR, and -5BR series turbofan engines. This proposed AD was prompted by a report of a rim/web separation of a first stage low-pressure turbine (LPT1) rotor assembly. This proposed AD would require replacing affected LPT1 rotor assemblies with LPT1 rotor assemblies eligible for installation. We are proposing this AD to prevent uncontained disk separation, leading to fuel tank penetration, fire, personal injury, and damage to the airplane.