Andy, my primary flight instructor, has always described a pilot’s license as “a license to learn”. This may sound trite, but it’s true… if you’re doing things the right way.
This week’s FLYING LESSONS newsletter contained an interesting factoid: the Australian Transport Safety Bureau says that partial loss of power is three times more likely than complete engine failure. After reading the report, I am forced to agree with Thomas Turner that partial-power operation is under-taught; I know that in my relatively limited experience none of the instructors I’ve flown with mentioned how to deal with it or even how to recognize it.
Recognition, of course, sounds like it should be pretty easy: is the engine making as much power as it should? In a car, you can tell by your forward speed and/or acceleration: does the car accelerate normally when you push on the accelerator? There are also audible cues that may tell you whether the engine is working normally. In an airplane, the same audible cues may exist, but airspeed and climb performance are just as useful as the sounds you hear. If you have fancy engine instrumentation, then it may give you information such as cylinder head temperatures that tell you what’s going on.
The ATSB report calls out a fairly straightforward procedure for dealing with partial power loss: lower the nose to maintain best glide speed, find a place to land, and do so as soon as practical. No turns under 200′, and no troubleshooting the engine unless you have sufficient altitude to do so. It also goes into some detail about potential causes of partial power loss, including spark-plug fouling, fuel contamination, and problems with carburetor heat. All of these are things I will be more mindful of as part of my preflight and in-flight operations.
Always something new to learn…
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