Good post Michael! Very interesting read. That video you posted is one of my favorites. Just love the professionalism. It's amazing to see what seemed to be a perfectly executed emergency procedure.
When you talk about the difference in priority between "saving the aircraft" and "saving the passengers" I definitely understand what you mean when it comes to multi-engine airplanes. If an indication shows that something is wrong with an engine, shutting it down will prevent any further damage to it, but obviously jeopardize safety as you'll only have one left.
However, when you relate that to single engine emergency turn backs, I become a little confused to be honest. The way I see it, if the airplane gets damaged then the passengers will most likely be damaged. Also, if the passengers make it without any injury, usually that means that the airplane is in good condition as well. Therefore, both priorities (with safety as the main one of course, always) should lead to the same decision.
bodypilot: why do you suggest Vx?
I did some experimenting with climbing out at Vx and Vy, and surprisingly enough the differences were not too great in terms of altitude gained vs time. At 50 seconds with Vy I made it to 600 feet, 500 with Vx. Then of course this is something that should be tested several times since once is not enough as the execution of the climbout will vary in quality etc.. What also seems to matter a lot is how quicly one accelerates to Vy during the climb.
What I did notice when trying to turn back after pulling the throttle to idle to simulate an emergency turn back at Vx (with a few seconds reaction time), was that it was way easier to stall than what I expected. Since the speed is so low, you can't go directly in to the turn as you could with Vy. You had to pitch forward and build sufficient speed first, and then make the turn. With Vy, since you are way above both the stall speed and the best glide speed you could go directly into the turn and then pitch down to keep the speed up. This will for sure increase the 100 foot advantage Vy had over Vx, even though Vx allowed me to be closer to the runway.
Here is a podcast about the emergency turn back by someone who is supposed to be a well recognized CFI:
http://traffic.libsyn.com/tfpflyingv...urn_tfp_vt.m4v
His name is Jason Miller and has a bunch of instructional videos at
Aviation Podcast - The Finer Points
Enjoy!