AOPA ASI Turnback Video

Jim K

Jim K

Final Approach
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ASI just released their video on "the impossible turn". As usual it's very well done.

I was somewhat surprised to see how much difference there was between the slow & fast airplanes.

Obviously this has been on everyone's mind since the event in Florida. I haven't tried the turnback maneuver (except at altitude), but I have been working on power off 180's. They're easy & fun in the archer, but the first one i tried in the lance wasn't even close to making it from our 750' pattern. I resolved to take my cfi up and see if he can improve my technique.

There may not be an altitude from which a turnback make sense in the lance. My 8000' home drome might work (which is why I always use full length), but a 4000' strip probably wouldn't. I'm wondering if there's a case for climbing at a slower speed with some flaps in those cases, but Vy is probably still safer.

My only gripe with the video is they share the obsession everyone has with making it back to the runway. If my engine quits, I would be perfectly happy to land in the grass anywhere on the airport property. If I have to crash, I'd much rather do it where ARFF is seconds away.
 
very well done video. I think the most important take away is you need to be proficient and with our small tin cans like a archer or 172, this can be done, but only under right conditions, DA etc. too many cards needs to be stacked in your favor before your bacon can be saved.
 
I would have liked to see each airplane loaded to maximum gross weight. Additionally, like most retracts the Bonanza has a high best glide speed. In the case of the A36 the glide speed is 70% above stall speed which is about double the margin above stall as the 172N. Best glide speed may not be the most effective speed for a turnback due to the large turn radius.
 
I’m glad they used such different aircraft for this. It highlights that there is not one right answer. Your plane, your skill, weather, and runway environment all play a part. Well done video in my opinion.
 
I'm sure I'm missing something; if the A36 was able to complete 360 degs. of turn within 1,000' at altitude, why was it unable to do so near the surface? I could see if the radius was so large, he'd fly downwind past the approach end, but this didn't seem to be the case. The video shows him starting the maneuver at 1,000' MSL which would be only 435' AGL (KMRB IS 565' MSL.)

Maybe they were setting the altimeter the way an airshow performer would making AGL=MSL? But if this was the case I go back to the question: Why can one not do at the surface what one could do at altitude? I would think the denser air would be beneficial.
 
Cogito said:
I'm sure I'm missing something; if the A36 was able to complete 360 degs. of turn within 1,000' at altitude, why was it unable to do so near the surface? I could see if the radius was so large, he'd fly downwind past the approach end, but this didn't seem to be the case. The video shows him starting the maneuver at 1,000' MSL which would be only 435' AGL (KMRB IS 565' MSL.)

Maybe they were setting the altimeter the way an airshow performer would making AGL=MSL? But if this was the case I go back to the question: Why can one not do at the surface what one could do at altitude? I would think the denser air would be beneficial.
Click to expand...
I don’t know the answer relative to the video, but in the real world that’s one of the reasons that the maneuver is discouraged...people find out too late that it’s not working out the way it does at altitude.
 
As most debates end up...it depends. The world isn't black and white, its many shades of grey.
 
Cogito said:
I'm sure I'm missing something; if the A36 was able to complete 360 degs. of turn within 1,000' at altitude, why was it unable to do so near the surface? I could see if the radius was so large, he'd fly downwind past the approach end, but this didn't seem to be the case. The video shows him starting the maneuver at 1,000' MSL which would be only 435' AGL (KMRB IS 565' MSL.)

Maybe they were setting the altimeter the way an airshow performer would making AGL=MSL? But if this was the case I go back to the question: Why can one not do at the surface what one could do at altitude? I would think the denser air would be beneficial.
Click to expand...

That's a very good catch, but I suspect they might have adjusted the altimeter setting to show AGL.

I can think of three reasons why it would have worked at altitude but not during landing. At altitude, they did a continuous 360 turn. During the landing, they had to roll out of the 270 turn and then roll into the second turn. This adds time (and altitude). Second, losing exactly 1000 ft means you will be scraping the ground as you roll out on final. I would estimate one would need at least 200 ft on final to even call it a final. That means they needed 1200 ft of altitude to make a successful landing. Third, just because you execute the 270+90 turn does not mean you will be aligned with the runway. You may successfully make the turn, but you might be aligned with a corn field instead of the runway.
 
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Cogito said:
I'm sure I'm missing something; if the A36 was able to complete 360 degs. of turn within 1,000' at altitude, why was it unable to do so near the surface? I could see if the radius was so large, he'd fly downwind past the approach end, but this didn't seem to be the case. The video shows him starting the maneuver at 1,000' MSL which would be only 435' AGL (KMRB IS 565' MSL.)
Click to expand...

I believe the maneuver was started at 1,000 AGL for simulation purposes, but either way...

One thing that doing this drill at altitude doesn't account for is your movement over the ground. By the time the Bonanza was at 1,000 AGL, he was no longer over the airport property. He had the altitude to make a 360 degree turn, but he was still at least 1/2 mile away from the airport without enough altitude to glide back. Making the turn is only part of the equation. That is why the answer to this question is...maybe. There are a lot of variables that will affect the outcome, wind, temperature, density altitude, aircraft's glide performance, pilot's proficiency and skill, and a small dose of luck.

One thing they simulated a 3 second response time. For a pilot that had mentally prepared themselves on what they were going to do, that might be right. For the pilot that is a little less proficient, or wasn't expecting the engine to fail at that moment, 3 seconds might not be enough.

Just imagine you just took off, beautiful day, can already taste the pancakes you are going to get at the breakfast. Perhaps a passenger talking to you. Suddenly the engine rolls back and gets quiet. You glance down confused. Stall horn starts to blare. Oh #@#$ nose down. Do I go forward or turn? Ok I'm going to turn. Which way do I turn? How far is the airport? Ok let's turn....How much time did those mental gymnastics take. And that's if you manage to control the total helmet fire that Martin and Doug talked about.
 
I believe this issue with the A-36 was not that they couldn’t turn far enough, it was they were to far from the runway. That would be a function of angle of climb and angle of glide.

as already expressed before I answered.
 
midwestpa24 said:
I believe the maneuver was started at 1,000 AGL for simulation purposes, but either way...

One thing that doing this drill at altitude doesn't account for is your movement over the ground. By the time the Bonanza was at 1,000 AGL, he was no longer over the airport property. He had the altitude to make a 360 degree turn, but he was still at least 1/2 mile away from the airport without enough altitude to glide back. Making the turn is only part of the equation. That is why the answer to this question is...maybe. There are a lot of variables that will affect the outcome, wind, temperature, density altitude, aircraft's glide performance, pilot's proficiency and skill, and a small dose of luck.

One thing they simulated a 3 second response time. For a pilot that had mentally prepared themselves on what they were going to do, that might be right. For the pilot that is a little less proficient, or wasn't expecting the engine to fail at that moment, 3 seconds might not be enough.

Just imagine you just took off, beautiful day, can already taste the pancakes you are going to get at the breakfast. Perhaps a passenger talking to you. Suddenly the engine rolls back and gets quiet. You glance down confused. Stall horn starts to blare. Oh #@#$ nose down. Do I go forward or turn? Ok I'm going to turn. Which way do I turn? How far is the airport? Ok let's turn....How much time did those mental gymnastics take. And that's if you manage to control the total helmet fire that Martin and Doug talked about.
Click to expand...
This is why you brief the turn before takeoff if you plan to do it after an engine failure. You brief the altitude (based on the factors discussed above) and direction of turn (based on wind and terrain). If not, just don’t try it.

Not disagreeing, just adding perspective for other newbies like me who may not have recently been trained on this.
 
Jim K said:

ASI just released their video on "the impossible turn". As usual it's very well done.

I was somewhat surprised to see how much difference there was between the slow & fast airplanes.

Obviously this has been on everyone's mind since the event in Florida. I haven't tried the turnback maneuver (except at altitude), but I have been working on power off 180's. They're easy & fun in the archer, but the first one i tried in the lance wasn't even close to making it from our 750' pattern. I resolved to take my cfi up and see if he can improve my technique.

There may not be an altitude from which a turnback make sense in the lance. My 8000' home drome might work (which is why I always use full length), but a 4000' strip probably wouldn't. I'm wondering if there's a case for climbing at a slower speed with some flaps in those cases, but Vy is probably still safer.

My only gripe with the video is they share the obsession everyone has with making it back to the runway. If my engine quits, I would be perfectly happy to land in the grass anywhere on the airport property. If I have to crash, I'd much rather do it where ARFF is seconds away.
Click to expand...

I haven't done Power off 180's in a Lance, but have in a Cherokee 6. The trick to making them successful is lots of speed and a vary high Descent rate. They happen very fast. I could easily see that a turn back the runway in it would be very challenging or impossible. Does that Lance POH recommend pulling the prop back (low RPM) for emergency landings?, Minimum flap will also help a bit.

Brian
CFIIG
 
brcase said:
I haven't done Power off 180's in a Lance, but have in a Cherokee 6. The trick to making them successful is lots of speed and a vary high Descent rate. They happen very fast. I could easily see that a turn back the runway in it would be very challenging or impossible. Does that Lance POH recommend pulling the prop back (low RPM) for emergency landings?, Minimum flap will also help a bit.

Brian
CFIIG
Click to expand...
The POH is pretty thin. They publish a gear up best glide speed and that's it. You're left to your own devices beyond that. During my transition training, we did demonstrate that pulling the prop all the way back makes a big (100-200 fpm) difference. I didn't do that, so that is the lowest-hanging fruit.

I also did not use any flaps, but I did drop the gear as I was afraid of forgetting it if I left it until short final. I wasn't even close to making it. I think it would've taken 1500 feet, and I was pretty tight, maybe 1/2 mile from the RW on DW. That's the reason I'd like to do it with my cfi; another set of eyes with more experience to make sure I don't go in gear up. In a real engine out, I think I'd just leave the gear stowed unless i actually needed the drag.
 
In the Florida case, he wasn't trying to make the runway he took off from. Was trying to make the parallel. But the point of the video was made. There's a lot to process with precious seconds ticking where it's probably a better idea to find somewhere in front of you. While trying to restart. Granted my base is 3200', so that makes a turn back less of an option.
 
Cogito said:
I'm sure I'm missing something; if the A36 was able to complete 360 degs. of turn within 1,000' at altitude, why was it unable to do so near the surface? I could see if the radius was so large, he'd fly downwind past the approach end, but this didn't seem to be the case. The video shows him starting the maneuver at 1,000' MSL which would be only 435' AGL (KMRB IS 565' MSL.)
Click to expand...

I had the exact same question. Since climb gradient was completely overlooked in the video, I suspect he climbed more steeply in the 360 test portion than he did in the actual takeoff/climbout from the airport.

upload_2021-6-5_12-54-7.png
 
dmspilot said:
I would have liked to see each airplane loaded to maximum gross weight. Additionally, like most retracts the Bonanza has a high best glide speed. In the case of the A36 the glide speed is 70% above stall speed which is about double the margin above stall as the 172N. Best glide speed may not be the most effective speed for a turnback due to the large turn radius.
Click to expand...

I had the same thought. When the engine tanks, for that first 180 turn around I really don’t want to -glide- anywhere. I’d like to be able to hover and spin the nose around 180 degrees without actually -going- anywhere.

Wouldn’t a minimum sink rate speed be more appropriate here than best glide? Once I’m spun around, then I may very well need best glide to get back over the fence again.


Sent from my iPhone using Tapatalk
 
Minimum sink will generally result in less horizontal distance covered. The goal is to make it back to the airport or some other suitable landing area.
 
crash7 said:
When the engine tanks, for that first 180 turn around I really don’t want to -glide- anywhere. I’d like to be able to hover and spin the nose around 180 degrees without actually -going- anywhere.
Click to expand...

upload_2021-6-5_14-37-48.png
 
write-stuff said:
Minimum sink will generally result in less horizontal distance covered. The goal is to make it back to the airport or some other suitable landing area.
Click to expand...

Agreed. My point was that first bit of the turn, I want to avoid getting to far away. So, I really don’t want to glide.
Once I’m pointed back at the runway, then best glide to get there.


Sent from my iPhone using Tapatalk
 
45° is generally taught because it reduces the turn radius (obviously, a good thing). I teach the maneuver using 30°. While it does result in a wider turn radius, it's not much wider. And the altitude loss at 45° vs 30° is almost the same (in most GA airplanes). What you get at 30° is a wider margin between best glide speed and "stall speed". This makes this high precision maneuver easier to do with an increased safety factor.
 
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