(Acknowledgements: GASCO Flight Safety/Matt Lane)

Matt says that in many instruction programmes the emphasis is placed upon total EFATO, whereby the Instructor retards the throttle to idle in the climb-out and announces the simulated engine failure; whereupon the Student adopts glide attitude and speed, carries out drills and proceeds with the approach for a forced landing ahead. The Instructor then calls for go-around when satisfied with the Student’s response. And certainly in the event of either Fire or Mechanical Failure, immediate total engine shutdown followed by a prompt forced landing is obviously the procedure to follow and thus should be trained for accordingly.
However, it is very likely that on occasions during their flying lives pilots will encounter power loss due to Non-Mechanical Failure, where a propeller may progressively slow down to windmilling for no immediately-apparent reason, or where there is a reduction in power or a degree of rough running caused perhaps by an incorrect control selection by the pilot, or by a fuel-flow/air-flow issue due to possible carburettor icing, or by a minor mechanical or ignition system issue. In such cases the power loss may be partial rather than total, and may therefore not require an immediate shutdown as trained in respect of EFATO.  
Certainly, Matt Lane’s own career has featured only one total engine seizure, whereas there have been several issues of partial power loss on climb-out, and so he includes an un-briefed PEFATO scenario in his course material. He will reduce power during the climb-out to cruise setting and announce for example “simulated rough running and vibration, touch drills only, continue your response until told to go-around”, and then observe the reaction of the Student which will generally be one of the following in the most likely order:
  • Immediate pitch down and setup for forced landing ahead, with throttle left untouched resulting in a fast and high approach inappropriate for a forced landing
  • Aircraft levelled off to stagger on at low level while the Student wonders what to do
  • An un-briefed and uncontrolled attempt to turn back towards the airfield
  • A vain attempt to maintain the climb in the face of falling airspeed until approaching stall
Any of the above would probably result in an undesirable outcome following a missed opportunity for recovering the situation, and when presented with this scenario the Students’ response in most cases has been complete surprise, having been conditioned to expect a total EFATO exercise.

So, Matt says, we have three choices to counter a partial EFATO situation:
  • Resolve the problem and safely climb away (carb heat? fuel pump? throttle vibrated away from full power? passenger accidentally altered a control?)
  • Commit to forced landing ahead (power off, shutdown, perform as for total EFATO)
  • Use residual power if sufficient to manoeuvre back to the airfield or at least a  more favourable landing area
Matt’s procedure for dealing with PEFATO is summarised as follows:
  • Pitch down and maintain at least Best Glide Speed
  • Confirm full throttle
  • Assess performance
  • If above 500ft and able to climb or maintain level flight:
  •        Consider turning downwind, or manoeuvre to a desirable landing area
  •        Prepare for Glide Approach
  •        If time allows, perform non-mechanical failure actions
  •        If engine fails to recover, position for Glide Approach
  •        When committed, close throttle and perform forced landing
  • If below 500ft and unable to climb, commit to landing ahead, close throttle, and perform forced landing as per total EFATO procedure