Practicing stopped prop

Brad W

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The idea of intentionally stopping the prop has always seemed very irresponsible to me
but
I also wish that at some point I had an instructor bold enough to practice it with me. Is that weird of me?

Youtube thought that I should watch this old video...so I did

basically the summary is this;
student pilot solo, the throttle will not retard...stuck full throttle
he gets a couple of different suggestions from folks on the radio
ultimately a CFI tells him to practice killing and restarting the engine using mixture
I thought that it seemed like a good suggestion for him to practice that a few times before he gets low.
His first practice attempt stopped the prop and he didn't get it restarted
successful dead-stick landing

Luckily he was in a good position when he made his first practice attempt! Could have gone badly had he not been in just the right position in the pattern!

My primary instructor, starting with the very first flight, taught all landings like this - downwind abeam the numbers.... throttle to idle. I'll call that my perch point

I personally think this was very wise, but also maybe just a bit misleading. Back when I was actively flying even as a student I was pretty solid making the runway and even spot landings because of this approach.

While I was listening to this video, I was thinking that if this had happened to me as a student, especially having had some prior solo experience and practice... I think that if I'd have set myself up at TPA on a normal downwind, and then pulled the mixture just a little before reaching abeam the numbers (because speed is higher)...that I probably would be able to slow enough and reach that perch point and a more normal downwind speed, and make it pretty much a normal landing. Easy peasy.

But the thing is, I never had practiced such a thing....would I cut the mixture midfield? would that have been enough time to slow it up? earlier? later?... and what effect would the stopped prop have on my glide through base and final?

I've always wondered though, how well would I have done if say for example the engine quit at some point in the pattern when NOT abeam the numbers.... or if I found myself at some altitude other than TPA when abeam the intended landing point say if doing an off field engine out into a clearing.
 
:yeahthat:

I have not done it personally, but I've been told that it takes lot more airspeed to get the prop going again than one might think.
 
Never turn a simulated emergency in a real emergency. Stopping the prop is brain dead stupid.

Also a stuck/broken throttle should be one of the emergency procedures you covered with student presolo including a power off 180 or 90 in this situation.
 
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Personally, I think the kill/restart practice advice was dumb. Student knows how to stop the motor and, as exhibited, there is no guarantee of a restart.

Better advice would be to declare an emergency, have ATC find me the longest suitable runway, setup for a straight in, and kill the motor when the runway was assured.

Something a CFI can do with a student is practice no flap landings to introduce the concept that touchdown can occur safely even if you’re faster than 1.3Vso on final.
 
:yeahthat:

I have not done it personally, but I've been told that it takes lot more airspeed to get the prop going again than one might think.
It does. BTDT, with a 150. Dove to Vne and the prop wouldn't start. Had to bump the starter. Now, if the starter had chosen that time to retire, I'd have been in trouble. I don't recommend doing this, especially over populated areas. That's just dumb.

On the other hand, I had to bring the nose up to near stall to get it stopped in the first place. A geared engine would stop a lot sooner.
 
I have a cfi friend who’s that guy at the airport that’s flown it all, and could fly your kitchen table if you mounted a prop on it. He used to demonstrate how much extra glide stopping the prop could give you until the day the pull cable starter handle pulled all the way out in his hands, the cable had broke. He said that 150 needed an absurd dive to get the prop to spin- he never demoed it that way again!

My poh says the old Mooney has a 10:1 glide ratio with windmilling prop but a 12:1 if your prop is stopped. 10:1 ain’t to shabby on its own- I think I’ll take the 10:1 if ever in that spot all goes quiet vs an unpracticed maneuver in a bird that isn’t a benign staller…
 
This happened to me once in a Pitts (metal prop, Lycoming IO-360), stuck at full power. Did a high speed spiral down to pattern altitude, entered a normal pattern and pulled the mixture at mid field and landed like every other landing I ever did in these airplanes. What struck me is that the prop continued to windmill through the entire approach and landing and didn't come to a complete stop until I'd coasted off the runway onto the intersection at very low speed. I could have pushed the mixture back in at any point during the landing process and gone around if needed. The windmilling prop with no power really felt no different than the engine running at idle on approach. Interesting that the prop actually stopped on him inflight here.

IMO it was terrible advice to suggest he fly a straight in approach from many miles out. Also IMO solo student pilots should be comfortable doing a power off landing from downwind in a trainer. Just fly a normal pattern, pull the mixture on downwind and land the thing. Push the mixture back in and try again if you see the prop blades really starting to go around slowly and if you don't like the look of your position.

I also wonder if he was unable to restart in the air because he left the mixture in the idle cutoff position. Normally air starts are no problem as long as your starter works.
 
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So in the wide open throttle scenario…

What say the brain trust here: cutting mags on the glide in, or mixture? Both could cut power, and potentially be undone n redone if the prop doesn’t stop which it shouldn’t on a glide down to runway.

Many ww1 planes had no throttle but just a mag ground button the pilot could tap as they came into land to cut n add power. But that’s even more ancient tech than our GA birds… so just curious in the scenario what all would do.

I beleive I’d use mixture as it seems a safer route, but just curious what others thought.
 
So in the wide open throttle scenario…

What say the brain trust here: cutting mags on the glide in, or mixture? Both could cut power, and potentially be undone n redone if the prop doesn’t stop which it shouldn’t on a glide down to runway.

Many ww1 planes had no throttle but just a mag ground button the pilot could tap as they came into land to cut n add power. But that’s even more ancient tech than our GA birds… so just curious in the scenario what all would do.

I beleive I’d use mixture as it seems a safer route, but just curious what others thought.
Flipping the mags on and off will cause a backfire each time you turn the mags back on because of all the unburned fuel you're dumping into the cylinders and exhaust with the mags off and the mixture in. Not my choice, I'd use the mixture.
 
Many ww1 planes had no throttle but just a mag ground button the pilot could tap as they came into land to cut n add power.
Holding the mag button too long would cause the plugs to foul.

They did have a control for the air into the engine, and another for the fuel - but it wasn't like a "modern" carburetor where the fuel increases as the airflow increases. If you reduced the air, you also had to reduce the fuel at the same time to keep it running. And, if you wanted to add power, you had to add the air and the correct amount of fuel. Not something you would be wanting to **** around with on short final.

edit: https://en.wikipedia.org/wiki/Rotary_engine#"Normal"_rotaries
 
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Clearly y’all have never flown the rental death traps I did in the early 90s. Lol.

Didn’t need to practice. The stupid things were so poorly maintained they’d stall on final with full rich and carb heat applied.

Especially if you got slow. Hahaha.

lol lol lol.

Such pieces of chit. lol
 
Clearly y’all have never flown the rental death traps I did in the early 90s. Lol.

Didn’t need to practice. The stupid things were so poorly maintained they’d stall on final with full rich and carb heat applied.

Especially if you got slow. Hahaha.

lol lol lol.

Such pieces of chit. lol
But just think how much better trained you were…
 
But just think how much better trained you were…

Kinda. Maybe. Perhaps.

Not to rent the cheapest dog barf available…

The owner of the rental place was found dead in the apartment above the FBO of a cocaine overdose.

We (CFI and I) decided maybe it would be best to rent a Skyhawk from a more trustworthy place. lol lol lol
 
I did it Tuesday. It was in a twin, but it does give you a great appreciation of how much drag a stopped prop causes, instant brick-mode. Wouldn't generally consider it in a single.
 
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