C421 Engine Management

[provo]

Given the difficulties that rapid closing of the throttle(s) can cause on the C421 I'm interested in what operators do when practicing EFATO.
For example does anyone close the throttle completely and once correctly identified set zero thrust or is it case of treating any failure as gradual and setting a particular manifold pressure? Grateful of any views.

[Malcolm G O Payne]

C421

My TRE always closed the throttle completely and when identified set zero thrust.

[411A]

Not a good idea to rapidly close the throttle with a GTSIO engine, for OEI flights.
This, over time, will cause de-tuning of the bifler pendulum dampers (counterweights), will wear the bushings on same, and eventually could cause one to be chucked out the side of the case, completely ruining your whole day...

A much better idea is to close the throttle slowly to just below the zero thrust condition, then carry out drills, as needed.
IF it is absolutely necessary to cause a rapid power loss, move the mixture to ICO, and leave the throttle where it is.
Then, follow thru with closing the throttle, simulate feathering the propellor, advance the mixture, and adjust to zero thrust.

Be kind to your engines, and they will serve you well.

[Lefthanded_Rock_Thrower]

Do the training in a C402, I have never failed a GTSIO-520, they do not make their TBOs as is, there is no way i would consider speeding up the process of Crank Case Fractures or gear box wear.

[411A]

While I would agree with your 402 suggestion, L_R_T, the idea that GTSIO engines almost never make TBO is completely dependant on the operator/pilots.
Service history has found that, if handled with the very necessary care and attention these engines deserve, they have proven to be very reliable in service, and can indeed be expected to reach TBO.
Recent problems with the starter adapter/dampers, notwithstanding...

Also, keep in mind that TSIO520 engines have counterweights as well, with the same cautions advised.