Safety Question

[colmbo]

One you should probably discuss is glide ratio.  From present position it is 1/2 the distance to the nearest airport.   

[earl1937]

One you should probably discuss is glide ratio.  From present position it is 1/2 the distance to the nearest airport.   

You make a good point and one of the reasons that I have avoided glide spec's is this: as you know, a whole host of varables are involved in the true glide distance of any aircraft, density altitude, head wind, tail wind, damaged or not, different weights of aircraft and where are not the aircraft's engine can be "feathered". Most single engine aircraft does not have a feathering prop, as there is no real purpose to have one. I have, over the years, heard argument after argument as to the benefit of slowing up until the prop on a single engine aircraft quits "windmilling" or should you continue to let the prop windmill, to harvest some perceived notion that the windmilling prop provides some thrust. Some people advocate that while the engine is windmilling, the oil pump is still working enough to reduce the prop to full decrease RPM, but I have always had my doubts about the advantage in that!
While working as a flight instructor in 1963, I had a student pilot working on approach to landing stalls with full flaps down in a Cessna 150. We lost 18 inches of one of the blades and I quickly snatched the nose up, pulled mixture and engine stopped immediately. Proceeded to land in a cow pasture just west of Fairburn, Georgia. Our head mech. replace the prop and after the farmer moved his cattle to one end of pasture, took off and returned to Charlie Brown airport. Had we been doing anything other than what we were doing at the time of separation, I would not be here typing this! All the other 12 Cessna 150's and Cessna 172's in the school fleet were promptly "magnafluxed" for cracks and one other aircraft had a small crack, but was not large enough to be a danger.

[colmbo]

Yeah, there is a lot of those things folks think is "the" thing to do in a situation that in reality offer little advantage and many times put you at more risk.

I think a stopped prop is much less drag than a windmilling prop but you probably lose any gain of stopping the prop in the act of getting it stopped.  On low powered aircraft it might be reasonably easy to get the prop stopped by slowing up but on higher powered aircraft you may have to slow below stall speed to get the prop stopped.  I've made 3 dead-stick landings and in all of them the prop continued to turn until I was on the ground.

As for pulling the prop RPM back I found that at least on my 182 it does reduce drag to reduce prop RPM.  I tested by bringing the power to idle and stabilized in the glide.  I would then pull the prop control out and the aircraft would gain 3-4mph in airspeed (I maintained the same pitch attitude).  When the prop control was pushed back in the speed would drop off.  Not a huge difference but if you're having to stretch to make a safe landing I'd certainly give it a try.

I'll bet that was interesting when the prop came apart.  Shake a bit did it?

[earl1937]

Yeah, there is a lot of those things folks think is "the" thing to do in a situation that in reality offer little advantage and many times put you at more risk.

I think a stopped prop is much less drag than a windmilling prop but you probably lose any gain of stopping the prop in the act of getting it stopped.  On low powered aircraft it might be reasonably easy to get the prop stopped by slowing up but on higher powered aircraft you may have to slow below stall speed to get the prop stopped.  I've made 3 dead-stick landings and in all of them the prop continued to turn until I was on the ground.

As for pulling the prop RPM back I found that at least on my 182 it does reduce drag to reduce prop RPM.  I tested by bringing the power to idle and stabilized in the glide.  I would then pull the prop control out and the aircraft would gain 3-4mph in airspeed (I maintained the same pitch attitude).  When the prop control was pushed back in the speed would drop off.  Not a huge difference but if you're having to stretch to make a safe landing I'd certainly give it a try.

I'll bet that was interesting when the prop came apart.  Shake a bit did it?

Actually, it was a quick viberation and cowling shake, because as soon as it happened, I pulled the nose up and pulled the mixture, and the aircraft did stall, but recovery was no problem and I had about 3,000 feet AGL to work with and the practice area that we used was over several cow pastures and corn fields. I was more  concerned about the nosewheel wiping out on rough ground and nosing over, but as it turned out, the grass all over that pasture was pretty short because of all the cattle feeding on it. The part I was most nervous about was the student pilot I had in the 150 was the wife of the District 9, Southeast district,(9 states), FAA flight surgeon. I knew that this forced landing was going to looked at very closely, but as it turned out, she and I both were interviewed by a local TV station the next day, explaining what happened. She went on to solo in around 9 hours or something like that and obtained her Private Pilot certificate in about 50 hours. She was an excellent student and those were the kind of students I really enjoyed working with!!

[Mongoose]

There... Are... Four... Lights!

No, the above pic's are just examples of what the different rotating beacons look like.

  "There... Are... Four... Lights!" was a reference to a Star Trek episode.  But I like your explanation of the lights.