Bryan Cotton wrote:Seems like a Sonex should be able to maintain altitude with one bad cylinder.
Maybe it would have (others have), but it doesn't sound like the pilot tried that before executing the turn that led to the stall and "spiral".
A Sonex isn't a sailplane, but it glides safely if the critical AoA isn't exceeded. It remains controllable to low airspeeds, and is structurally tough enough to provide good protection if set down in good/marginal terrain in a normal attitude and near Vso.
But we don't, and we can't, know all the factors that influenced the pilot's decisionmaking in this case. He had a lot of experience, surely could have recited the correct procedures based on a given situation, had practiced loss of power scenarios scores of times in sophisticated simulators, and yet we have this result. "Knowing" and "doing" aren't the same thing, and I'd be the last to say that I would surely have come out any better than he did.
A possibly related comment: Aluminum heads are soft, and the spark plug hole threads are easily damaged even if a great care is taken to avoid cross-threading, overtorquing, etc. As mentioned in another thread, many folks with a lot of experience trust the new Timesert thread repair method more than the older Helicoil method.
Posted: Sun Dec 13, 2015 3:51 am