Jet Engine Throttle Linkage Loss

[Milt]

During the 1960s a USAF B57 flew from the USA to Australia with throttle linkages to both engines having unsecured taper pins in the linkages.

Fortunately the right engine throttle linkage taper pin fell out whilst the aircraft was taxying using low power. The engine was shut down without delay. It is unknown whether the engine had continued at the power setting previously set or whether it reduced to idle.

Does anyone know whether design specifications for jet engine control units require these to go to engine idle following a severance of the pilot's throttle linkage.?

I once had such a failure in a Mustang climbing through 15,000 ft. The engine went to idle followed by a compulsive return to a runway. Not sure about jet engines. Perhaps they are all different.

If a jet engine stays at set power a landing would require some tricky judgement as to when to shut the engine down on final approach especially if it is the only engine you have.

Comments?

[FE Hoppy]

Mechanical linkage?
So last century.

[H Peacock]

I'm not aware of any mechanical throttle system designed to fail-safe to idle. Indeed, on balance I would prefer an engine to remain at the previous power setting. At least it would probably give you more chance of reaching a suitable destination to attempt recovery.

In all of the single engined aircraft that I've flown - piston, turboprop and jet - the teaching for a 'stuck throttle' was to do your best to home towards a suitable airfield before completing a modified forced landing pattern. At a suitable point the engine would invariably be shutdown.