Impossible turn practice

alfadog

alfadog

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alfadog
Impossible turn practice today at KTNT - video

Took the Arrow over to KTNT (see my thread in Flight Following for a vid of the field). Had the 10,499' field to myself. Among other things, worked on the "impossible turn" from about 600'. This is the third and last. The others weren't bad but on those but I forgot I "had no engine"and added a bit of power to smooth out the flare. LOL.

http://www.youtube.com/watch?v=UssPE3tHz_A
 
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From 600' AGL with an arrow, not bad. Gear down with the power failure / speed reduction? Or is the auto-extend system deactivated? a lot of people forget and may not train at altitude that you need that first turn at 30-45 degrees of bank and it's a 225-230 degree turn, to get back to the runway, then a 45 to the other side to line up.

I see you overshot the last turn to line up, tsk tsk.

Gear is normally up by 500' AGL on most departures, gear auto extend would increase the drag / sink rate.

If the gear auto-extend is disabled, don't FORGET the GEAR, GUMP when you get the turn completed.

We teach 200ft launch failure (broken rope) and return to landings. But we have an L/d of 23/1 in our primary trainer. Not 7 or less.
 
BillTIZ said:
From 600' AGL with an arrow, not bad. Gear down with the power failure / speed reduction? Or is the auto-extend system deactivated? a lot of people forget and may not train at altitude that you need that first turn at 30-45 degrees of bank and it's a 225-230 degree turn, to get back to the runway, then a 45 to the other side to line up.

I see you overshot the last turn to line up, tsk tsk.

Gear is normally up by 500' AGL on most departures, gear auto extend would increase the drag / sink rate.

If the gear auto-extend is disabled, don't FORGET the GEAR, GUMP when you get the turn completed.

We teach 200ft launch failure (broken rope) and return to landings. But we have an L/d of 23/1 in our primary trainer. Not 7 or less.
Click to expand...

I left the gear up until the runway was assured. In a real-life scenario, I would land gear-up if that is what it took to make a safe landing.

The auto-extender is in override position. I leave it there because my A&P and I were not able to get it adjusted correctly last month during the annual. It works but I am not especially keen on its retract limit speed - too high.

Yeah, overshot a bit, I was busy. LOL. Had plenty of altitude.
 
You should have just told us you executed a last minute S-turn to bleed excess speed rather than that you overshot......you'll never be a politician. :D Nice work!!!
 
alfadog said:
I left the gear up until the runway was assured. In a real-life scenario, I would land gear-up if that is what it took to make a safe landing.

The auto-extender is in override position. I leave it there because my A&P and I were not able to get it adjusted correctly last month during the annual. It works but I am not especially keen on its retract limit speed - too high.

Yeah, overshot a bit, I was busy. LOL. Had plenty of altitude.
Click to expand...

Not sure I would want the override blinking light in my face all the time.
 
Re: Impossible turn practice today at KTNT - video

alfadog said:
Took the Arrow over to KTNT (see my thread in Flight Following for a vid of the field). Had the 10,499' field to myself. Among other things, worked on the "impossible turn" from about 600'. This is the third and last. The others weren't bad but on those but I forgot I "had no engine"and added a bit of power to smooth out the flare. LOL.

http://www.youtube.com/watch?v=UssPE3tHz_A
Click to expand...

Are you aware of the accidents that have occurred while practicing turnarounds at low altitude?
 
Re: Impossible turn practice today at KTNT - video

Palmpilot said:
Are you aware of the accidents that have occurred while practicing turnarounds at low altitude?
Click to expand...

Of course. I am also aware of accidents that have occurred during just about every other phase of flight training and flight in general. If you think it is your job to duplicate the screw-ups of others, it is best to stay on the ground.

This is basically a simple manuever not so very different from manuevering to land and definitely inherently no more "dangerous" that the engine-out practice commonly done from other positions in the pattern.

I am much more aware of the many accidents that occur because folks do not execute properly what is basically a simple manuever. If I practice it under calm and controlled conditions with engine power available then I am much more likely to successfully execute if the time ever comes (knock on wood).

Prior to doing this, I performed stalls in various configurations to verify that 105 mph, the best glide, gave me sufficient margin over the 1.19 - 1.41 max factor increase in stall speed to be expected during this manuever.
 
Ron Levy said:
How much below max gross were you? That will have a big effect on this maneuver.
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Good point. Factors would be the stall speed and the increased induced drag.

Don't have the POH in front of me but we can use this sealevel rule of thumb:

stall speed = 3.7 * square root of wing loading

Say I was at 2150 of 2650 lbs. To calculate the relative stall speed we can go

stall speed (full load) = square root of (2650/2150) * stall speed (light load) (The 3.7 factor will cancel out and wing loading is linear with weight so the wing area will cancel out also.)

That tells us that heavy stall = 1.11 x light stall. That is interesting but is not an issue provided I hold the min glide speed.

The induced drag is another. I can see 500 lbs of sandbags in my future. :D
 
Re: Impossible turn practice today at KTNT - video

Palmpilot said:
Are you aware of the accidents that have occurred while practicing turnarounds at low altitude?
Click to expand...

Are you aware of the accidents that have occurred while practicing takeoffs and landings?
 
Re: Impossible turn practice today at KTNT - video

Palmpilot said:
Are you aware of the accidents that have occurred while practicing turnarounds at low altitude?
Click to expand...

Just my two cents worth, but as a guy who did most of his business at low altitude, it seems that the time to find out what your airplane will do in that circumstance is when you know it is going to happen and you have a good engine. Developing a protocol which includes altitude limits for beginning the maneuver seems like a good idea to me. I saw nothing on the video which even approached unsafe flight.
 
Re: Impossible turn practice today at KTNT - video

RoscoeT said:
Are you aware of the accidents that have occurred while practicing takeoffs and landings?
Click to expand...

The reason I asked the question is that an instructor I know who has expertise on this subject, and has experimented with it extensively in the pattern, advises against practicing it at that low an altitude. However, I have to admit that we really don't have the data that would be required to determine whether practicing it in the pattern improves the fatality rate or worsens it compared to practicing it at altitude. :dunno:
 
Re: Impossible turn practice today at KTNT - video

Palmpilot said:
The reason I asked the question is that an instructor I know who has expertise on this subject, and has experimented with it extensively in the pattern, advises against practicing it at that low an altitude. However, I have to admit that we really don't have the data that would be required to determine whether practicing it in the pattern improves the fatality rate or worsens it compared to practicing it at altitude. :dunno:
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When I would practice it, I personally took a very trusted instructor with me.
We actually both practiced it.
With the caveat, if it looks like "I" am in trouble SAY SOMETHING, from your point of view. That went for both of us.
We had trained together for MANY hours, (PP and IR).
With that said, the best I could ever do in a Warrior taking off from a 3,000 foot strip on a spring day was 400 agl and be able to get it back on the runway. No hot temps or crazy winds just an average day. (we did it more than one day)
It wasn't the turn so much as getting things lined back up and actually getting it on the ground and STOPPED.
We did many a "go around" practicing.
As stated above, the time to do this is when things are calm, and you have other options.
Then you can learn what you and your planes capabilities are.
 
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I do turn back practice frequently in the Chief. I always have at least 500' of air below me when I complete the maneuver.

I know how to land -- why would practicing this at actual AGL be beneficial?

:dunno:
 
dmccormack said:
I do turn back practice frequently in the Chief. I always have at least 500' of air below me when I complete the maneuver.

I know how to land -- why would practicing this at actual AGL be beneficial?

:dunno:
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Do you establish youself at 1000' in the position relative to the runway end that you would have at your actual target altitude in a normal takeoff?

I find that practicing at the actual altitude provide me a richer learning experience, i.e. I learn more and better. YMMV. I know you are not afraid to bank your Chief below 500' :D
 
Reducing indecision time can be useful. Every time I am on aero-tow in my glider, I go over the decision points. At 200' AGL I am saying to my self I'm at turn back altitude. That doesn't mean I have to but means I can. This is amended at each airport for it's configuration and weather, so it might be a little higher at some and a little lower at others. The point is, there is a time that if I have a rope break, I don't spend any time saying, "oh my god, what do I do?" I initiate action immediately.
I've practiced the turn a couple of times in my light sport at gross weight at altitude with an observor pilot and find 450 is more than adequate. I used a four second delay in reacton time. I should probably practice some more and with good pre-briefing am sure I could get to 400' comfortably.
 
Depending on the airport, you may not need to actually return to the same runway you departed from - that could save you some unnecessary turns if your initial turn is in the right direction.
 
I just wanted to point out that you rotated at the fourth taxiway from the end (perpendicular) and landed at the third taxiway from the end (angled) with I'd say 1 to 2 thousand feet difference. If you had rotated at the end of the runway I don't think you would have made it, or at least would have had to be more aggressive in the turn and maybe delay gear or abandon gear.
 
Captain said:
I just wanted to point out that you rotated at the fourth taxiway from the end (perpendicular) and landed at the third taxiway from the end (angled) with I'd say 1 to 2 thousand feet difference. If you had rotated at the end of the runway I don't think you would have made it, or at least would have had to be more aggressive in the turn and maybe delay gear or abandon gear.
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Affirm on that and good spot. I was just thinking about that earlier this morning. That runway is 10,499 feet long. Definitely atypical. Looks like I landed about 1500 feet down but, as you mention, I could have left the airplane clean. Will need to try it from a shorter runway next weekend. I also want to load some sandbags and bring it to gross and do some stalls, slow flight, and landings. I commonly do load it up and have noticed a difference but I want to get a real feel for what that difference is.
 
No, I'd stay with your long runway. Just use markers (like those taxiway intersections) to simulate the end of the runway. You've already boxed yourself in vertically with altitude, no need to box yourself in laterily as well.
 
Captain said:
No, I'd stay with your long runway. Just use markers (like those taxiway intersections) to simulate the end of the runway. You've already boxed yourself in vertically with altitude, no need to box yourself in laterily as well.
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Good point. I like it out there, too. Only 15 minutes away and quiet as can be. More than worth the few extra gallons to fly out there as opposed to X51 which is full of students in the pattern.
 
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