Turn backs and Mooneys

[Shadrach]

1 minute ago, AerostarDriver said:

Book best glide in my 71 E is 105 MPH prop wind milling, 100 MPH prop stopped. DMMS is 105 MPH as well. If you know a better speed I am more then happy to add it to my list.

Vbg is given with the airplane clean at max gross weight. At 1100 feet AGL I’d be concerned about running out of runway. You can see from Dave Keller‘s video that he actually needed to use brakes to avoid rolling off the end of the reciprocal runway. IIRC, He was at 500 feet AGL when his engine failed. 

[N201MKTurbo]

2 minutes ago, Shadrach said:

My best performance practicing this maneuver has always been to unload the wing while transitioning to a steep bank then pulling to just before stall (I get the horn well before the buffet).  I shoot for best glide after my turn.

This guy had an engine failure on downwind, not takeoff.

[N201MKTurbo]

12 minutes ago, AerostarDriver said:

Book best glide in my 71 E is 105 MPH prop wind milling, 100 MPH prop stopped. DMMS is 105 MPH as well. If you know a better speed I am more then happy to add it to my list.

My apology, I was thinking KTS.

[Shadrach]

8 minutes ago, N201MKTurbo said:

This guy had an engine failure on downwind, not takeoff.

That makes more sense. I often try to make the runway from abeam the numbers without touching the power. With the gear down there is barely adequate energy to fly a tight pattern in light winds. Much better to point straight at the threshold and align with the runway in ground effect.  A strong wind coming down the runway with runway at my 5 O’clock on downwind would probably push me towards putting it in a field rather than ending up in the culvert or highway before the approach end of the runway.

[Davidv]

On 6/4/2021 at 2:13 PM, A64Pilot said:

A lot depends on your climb airspeed, Seems everyone around where I live hangs it on the prop for a steep climb angle, while that gives them the most altitude in the shortest distance, it does not give best rate climb, and if they have an engine quit, they have to immediately nose over or they will be mushing if not in an actual stall. In my opinion it’s unsafe unless obstacles require it, and if they do, then your in the dead mans curve, just hope nothing happens.

‘So in my opinion someone who cruise climbs, say about 110k indicated in a J model and likely even faster in one of the big motor airplanes, has a lot better chance of pulling off the impossible turn.

‘It’s all energy management, speed and altitude are interchangeable, but I’d rather have a little extra speed than altitude because it’s human nature if the engine quits to hold attitude for a few seconds, and then your mushing if you were climbing at Vx.

It’s like a stall. if it’s truly a surprise, every pilot will initially try to raise the dropped wing with aileron, which of course is not what you want to do, it’s just muscle memory.

‘But given our better glide ratio, we have a much better chance of pulling it off, in my opinion, this is one of the times you’ll be loving that tendency to float on final

I believe once I get to 500’ at 110 kts I can make it, less than that maybe best to find a spot pretty much straight ahead without trees or between the biggest ones. This is a maneuver once comititted you must make, so give yourself some extra fudge, and don’t forget it’s a downwind turn too, so you need extra speed when that head wind becomes a tailwind.

Go out and practice it in the pattern, with plenty of altitude and watch for a stall in the turn, decide your own critical altitude, but leave some extra for time to figure out and accept that the thing has quit

 

Just watched the video, first a Bo drops like a rock, I’ve followed them and unless I’m way lower I can’t make the approach  with them.

‘I’m also not recommending maintaining 110 kts, but if the engine quits unexpectedly. I bet lunch you won’t be at 110 kts when you accept it.

‘Good video, I expected the RV suffered some from the Hersey bar wind too though.

On edit I disagree with the video, you don’t have to make two additional turns to line up on the runway, your successful in my opinion if you make the airfield. nice open fields with not much to hit. One thing that stuck with me from Military training was always crash inside of the fence, the fire trucks and ambulance can get straight to you, outside of the fence, maybe not.

I’ll take the altitude and distance to the airport over speed.  Usually people don’t stall/spin flying runway heading, it’s in the turn back trying to stretch the glide.  In any case, it’s going to require nosing over prior to the turn.  If they are still trying to climb or maintaining a nose high attitude while in the turn, neither Vx nor Vy would save them.

[AerostarDriver]

29 minutes ago, Shadrach said:

Vbg is given with the airplane clean at max gross weight. At 1100 feet AGL I’d be concerned about running out of runway. You can see from Dave Keller‘s video that he actually needed to use brakes to avoid rolling off the end of the reciprocal runway. IIRC, He was at 500 feet AGL when his engine failed. 

I have seen Dave's turn back, I would be concerned to take that as a rubber stamp that all cases are possible. A few things I remember from reading about it, when he had his engine failure he had a DA of -1825 Feet, I also do not believe he was at gross weight in a C model.

I can say that I am 99% positive that on the day I had my engine out, with the weather and weight conditions, I could not have made the turn back to the runway from 1000 feet. I fortunately was in the position I could make it to the runway but even then I was concerned I would not make it.

[Shadrach]

6 minutes ago, AerostarDriver said:

I have seen Dave's turn back, I would be concerned to take that as a rubber stamp that all cases are possible. A few things I remember from reading about it, when he had his engine failure he had a DA of -1825 Feet, I also do not believe he was at gross weight in a C model.

I can say that I am 99% positive that on the day I had my engine out, with the weather and weight conditions, I could not have made the turn back to the runway from 1000 feet. I fortunately was in the position I could make it to the runway but even then I was concerned I would not make it.

I misread your post. I thought you were doing a turn back from takeoff. Your comments make more sense knowing you were on downwind with the airport behind you and the plane dirty.

[A64Pilot]

1 hour ago, Davidv said:

I’ll take the altitude and distance to the airport over speed.  Usually people don’t stall/spin flying runway heading, it’s in the turn back trying to stretch the glide.  In any case, it’s going to require nosing over prior to the turn.  If they are still trying to climb or maintaining a nose high attitude while in the turn, neither Vx nor Vy would save them.

No, of course not, speed and altitude are interchangeable, it’s the basis of energy management, However almost any normal person if an engine quits even throughly trained ones freeze for a few seconds and do nothing while processing what’s happening, I assume that’s the reason for the 3 sec wait on the videos linked to. 

An aircraft at a high angle of attack climbing under high power will very quickly be at or close to stall within 3 set of the power being removed, so to make a turn much less a tight turn a strong nose down attitude will be needed and that goes against most people’s instinct, to shove the nose down hard at low altitude. 

For those with significant helicopter time this is actually a nearly identical to a helicopter autorotation, what’s different with helicopters and airplanes is a helicopter has a height/ velocity diagram, AKA the “deadman’s curve” There is a document you can refer to illustrate whether you can make it or or not, unfortunately there is no such graph for a turn back that I’m aware of.

If you look at one you will see that it takes an enormous amount of altitude to replace speed.

https://en.wikipedia.org/wiki/Helicopter_height–velocity_diagram

‘Then talk to a Crop Duster about his turns back to the field, whether a little extra altitude is preferable to a little extra speed.  The Crop Duster’s turn is pretty close to what we are trying here, When spraying a field the throttle remains set, your not jockeying the throttle constantly and it’s energy management.

The Vietnam era gun ship drivers doing a return to target turn is also pretty much identical, they are all energy management.

Probably one of the best examples of energy management on video is Bob Hoover’s demo flights in the twin Commander.

The “impossible turn” is energy management, but sometimes “speed is life”

On edit, if you have had mountain training, this is actually very close to a box canyon turn too, yes you have an engine then, but the terrain is rising faster than you can climb.

Edited June 7, 2021 by A64Pilot

[aviatoreb]

I don't know if a bigger engine Mooney can do the full turn back to runway at less than pattern altitude.

Does anyone know here?

In any case, getting back to the runway is the A+ solution if it is possible.  But there should be a consideration of a B- solution in those cases where the specific airport may present a rugged inhospitable environment for a straight ahead, like in an urban environment where there may be a bigger airfield and several runways.  For example many airports a 120 degree or a 150 degree turn back may allow landing in the grassy areas inside the fence (and remember in this video they were saying that really 360 degrees of turning is required to make it all the way back to the runway).

[EricJ]

14 minutes ago, aviatoreb said:

I don't know if a bigger engine Mooney can do the full turn back to runway at less than pattern altitude.

Does anyone know here?

In any case, getting back to the runway is the A+ solution if it is possible.  But there should be a consideration of a B- solution in those cases where the specific airport may present a rugged inhospitable environment for a straight ahead, like in an urban environment where there may be a bigger airfield and several runways.  For example many airports a 120 degree or a 150 degree turn back may allow landing in the grassy areas inside the fence (and remember in this video they were saying that really 360 degrees of turning is required to make it all the way back to the runway).

Since airports are clear of power lines, poles, cars, people, etc., I sometimes figure just getting it to the airport is desirable, getting it on a runway is a bonus. 

[A64Pilot]

9 minutes ago, aviatoreb said:I don't know if a bigger engine Mooney can do the full turn back to runway at less than pattern altitude.

 

Not to beat a dead horse, but it’s largely airspeed dependent as well as altitude, it’s actually energy dependent, but altitude and airspeed are pretty much interchangeable, the big motor guys pretty much do everything faster than us little motors guys and speed is energy.

‘It’s also I believe a logical argument that the big motor guys are climbing at a much higher gradient, so at pattern altitude they would be closer than my J. Might make an argument that they would be in better shape than a lighter Mooney with a smaller motor.

‘Then weight doesn’t affect glide distance, a big motor Mooney ought to have the same glide distance, excepting maybe the bigger prop will have greater drag, it will have a higher glide speed which will amount to a larger diameter turn of course, variables would be hard to quantify without test flights

[A64Pilot]

Just now, EricJ said:

Since airports are clear of power lines, poles, cars, people, etc., I sometimes figure just getting it to the airport is desirable, getting it on a runway is a bonus. 

It’s also often where a good fire truck and sometimes even an ambulance is located.

[Davidv]

54 minutes ago, aviatoreb said:

I don't know if a bigger engine Mooney can do the full turn back to runway at less than pattern altitude.

Does anyone know here?

In any case, getting back to the runway is the A+ solution if it is possible.  But there should be a consideration of a B- solution in those cases where the specific airport may present a rugged inhospitable environment for a straight ahead, like in an urban environment where there may be a bigger airfield and several runways.  For example many airports a 120 degree or a 150 degree turn back may allow landing in the grassy areas inside the fence (and remember in this video they were saying that really 360 degrees of turning is required to make it all the way back to the runway).

I’ve practiced turn backs and have done them in roughly 600-700 feet depending on conditions climbing at Vx.  I don’t have time to get in an argument with anyone over this, but in the heavier long body it’s all about being as close to the airport as possible.

[Vance Harral]

3 hours ago, Shadrach said:

I often try to make the runway from abeam the numbers without touching the power. With the gear down there is barely adequate energy to fly a tight pattern in light winds.

This is significantly different from my experience, which is interesting given that we're both flying F models.  But I think I know why...

When teaching the commercial power-off 180 to partners in our 1976 M20F, power is reduced to idle abeam the touchdown point, with the gear already down.  In light winds, if an immediate turn toward the runway is made at this point, there is far too much energy at the touchdown point to meet the commercial +100/-0 standard - unless you force the airplane onto the ground, which is an obvious no-no.  I teach them to wait a distinct 3 count after reducing power to idle before making the turn, unless there is an especially significant headwind component.

I'm sure the experience you are reporting for you airplane is what you actually see.  One explanation may be that our home drome is at 5050' MSL, and density altitude is usually higher than that, so less drag and faster true airspeed for the same indicated airspeed.  At what elevation/DA is your experience?

[A64Pilot]

22 minutes ago, Vance Harral said:

This is significantly different from my experience, which is interesting given that we're both flying F models.  But I think I know why...

When teaching the commercial power-off 180 to partners in our 1976 M20F, power is reduced to idle abeam the touchdown point, with the gear already down.  In light winds, if an immediate turn toward the runway is made at this point, there is far too much energy at the touchdown point to meet the commercial +100/-0 standard - unless you force the airplane onto the ground, which is an obvious no-no.  I teach them to wait a distinct 3 count after reducing power to idle before making the turn, unless there is an especially significant headwind component.

I'm sure the experience you are reporting for you airplane is what you actually see.  One explanation may be that our home drome is at 5050' MSL, and density altitude is usually higher than that, so less drag and faster true airspeed for the same indicated airspeed.  At what elevation/DA is your experience?

It’s how tight the pattern is, is the difference. You fly a tighter pattern, your closer to the runway.

‘I believe but am not certain that higher altitudes you will have a higher true airspeed due to thinner air, but you will also have a higher rate of descent due to thinner air, and your glide ratio will remain the same, at normal altitudes for an airport anyway.

Just as it does at higher weights 

[Vance Harral]

1 hour ago, A64Pilot said:

It’s how tight the pattern is, is the difference. You fly a tighter pattern, your closer to the runway.

Sure, but Shadrach specifically said "there is barely adequate energy to fly a tight pattern in light winds".  Again, just not my experience in the same airframe.

I don't have a good handle on the change in descent rate with change in density altitude, I could easily believe you're right that thin air is no better than thick.

Something we probably all agree on is, if the goal is survivability rather than meeting ACS standards, turn toward the runway ASAP.  Landing long/hot and running off the end of a good surface and/or into a fence at low speed, is a very survivable event.  Coming up short and stall/spinning trying to stretch the glide is not.

[Shadrach]

3 hours ago, Vance Harral said:

This is significantly different from my experience, which is interesting given that we're both flying F models.  But I think I know why...

When teaching the commercial power-off 180 to partners in our 1976 M20F, power is reduced to idle abeam the touchdown point, with the gear already down.  In light winds, if an immediate turn toward the runway is made at this point, there is far too much energy at the touchdown point to meet the commercial +100/-0 standard - unless you force the airplane onto the ground, which is an obvious no-no.  I teach them to wait a distinct 3 count after reducing power to idle before making the turn, unless there is an especially significant headwind component.

I'm sure the experience you are reporting for you airplane is what you actually see.  One explanation may be that our home drome is at 5050' MSL, and density altitude is usually higher than that, so less drag and faster true airspeed for the same indicated airspeed.  At what elevation/DA is your experience?

Field Elevation is 703’. DA’s range from a of ~3500 in summer to negative 3000 in winter. Our runway is 7000’. 
 

I was not suggesting that it was difficult to make the runway from abeam the numbers. I was suggesting there was barely adequate energy for flying normal pattern (I typically fly 1/2 mile legs).  Once we’re through annual I will go out and see if I’m mis remembering. When I practice High key/Low key engine out, I never drop the gear Low  Key unless I’m high and fast.

[Vance Harral]

Just now, Shadrach said:

I was not suggesting that it was difficult to make the runway from abeam the numbers. I was suggesting there was barely adequate energy for flying normal pattern (I typically fly 1/2 mile legs).

Ah, that's a big difference.  Agree there is "barely" enough energy to fly a typical rectangular pattern.  The CFI that was training me at the time showed me a power-off "180" with squared corners once, just to prove a point, but there's no room for mistakes... or headwinds.

[Shadrach]

26 minutes ago, Vance Harral said:

Ah, that's a big difference.  Agree there is "barely" enough energy to fly a typical rectangular pattern.  The CFI that was training me at the time showed me a power-off "180" with squared corners once, just to prove a point, but there's no room for mistakes... or headwinds.

I probably worded it poorly. It was mentioned in the context of another poster talking about losing his engine  on downwind at 1100 feet AGL with the runway behind him at the 5o’clock position.  I’m assuming he was on the right downwind well beyond abeem the numbers. By his description, he made it by the skin of his teeth threading the mains through the runway edge lights.

Edited June 7, 2021 by Shadrach

[Davidv]

Another reason to get that gear up as soon as you lift off the runway.  Poweroff 180s are done with the gear down which robs you of a ton of energy which is why you need to be so close to the airport at 1000 feet to make it.  If I have to do a turnback, I'm waiting until the last possible second (if at all) to get the gear down.

[Yetti]

I am not sure about the turns they are suggesting.  If you do this turn till you are pointed at the runway.  Use the final bit of energy to turn down the runway.  Or whatever energy you have left the ground is flatter around the runway so just put it down

[AerostarDriver]

1 hour ago, Shadrach said:

I probably worded it poorly. It was mentioned in the context of another poster talking about losing his engine  on downwind at 1100 feet AGL with the runway behind him at the 5o’clock position.  I’m assuming he was on the right downwind well beyond abeem the numbers. By his description, he made it by the skin of his teeth threading the mains through the runway edge lights.

I have done hundreds of power off 180s in my flying career. However, doing a power off 180 while also being a little over a mile downwind is clearly something else. I had two options, turn back to the airport or commit to the 4 lane road below me which looked like a parking lot. I debated retracting the gear but realized very quickly that I was at task saturation. Holding airspeed, maneuvering in the turn and attempting a restart while overtaking a 172 that was taking there sweet time landing and getting off the runway. 

I also want to point out that technically, the FAA does not see the power off 180 as a simulation of an emergency landing and that the PTS/ACS do consider it precision maneuver with the sample I have heard, "you are needing to land in a box canyon and land in the minimum distance" at least that is DPE had me do on my commercial check ride, power off 180 in to a short field landing. That being said, going forward I will be definitely be practicing different failure profiles. 

Edited June 8, 2021 by AerostarDriver

[PT20J]

Altitude equivalent of 90 kts:

Kinetic energy = potential energy

1/2*m*V² = m*g*h

where, m = mass, V = velocity in ft/sec, g = gravitational acceleration 32 ft/sec², h = height in feet

90 kts * 1.7 =153 ft/sec

153²/2*g = h

Or, h = 366 ft.  Assuming no losses in the conversion, of course.

 

[steingar]

This is a sort've nutzy cookoo topic.  If you've got farm fields in front of you, why turn back?  Remember, the most you're going to payout in an airplane crash is your insurance deductible.  If you have a field you can land in, the Mooney will protect you.  Keep it under control and you'll be just fine.

What if you haven't a field?  You still don't have to make a runway, the grass next to the runway is likely free of obstructions, at least formidable ones (I really don't care if I take out a landing light crashing the airplane).  Hence you might only have to make a 180. Heck, in the accident animation that started the video there were parallel runways, he only needed 180.

Me, I take off over neighborhoods.  I don't care, I'm turning back.  My thinking is not making it is no worse than landing straight ahead.  I have parallel runways, so I only have a to make 180.  And I usually take off over a farm field.  If I can make that I'll call it a success.  My job in a situation like this is to make certain everyone gets out OK.  The airplane is expendable.  I'll buy another.  Mooney made lots.

Am I practicing this?  Of course not!  Practicing at altitude with no surprise, no stress and no terrain is laughable.  Practicing at low altitude is dangerous at best.  Moreover, my engine might decide to puke at a different altitude than my "practice".  I think the biggest thing we need to do as pilots is brief the takeoff.  "What do I do if the mill takes a dump?".  Whatever that is, do it as quickly, smoothly, and safely as you can when the time comes.  I know I'm turning back from my home drone, I don't care.  There just isn't a down side so long as I keep the speed up.  Other runways may be different.

[PT20J]

I was out fooling around in my M20J last evening and tried the following experiment. I trimmed for a climb, clean, 85 KIAS, full power, at 2800 feet. Weight was about 2500 lbs. At 3000', I pulled the power, waited 3 seconds and began a 45 deg banked turn at 85 KIAS for a 270 deg heading change to simulate a course reversal and additional maneuvering. I did not put the prop in high pitch. All three attempts resulted in a 600' altitude loss. 

Why practice this? Because the maneuver is the entry to a spiral and the airplane has a strong tendency to diverge. It takes a surprising amount of back pressure to hold a constant airspeed and bank. However, too much back pressure tightens the spiral and will eventually lead to an accelerated stall. It takes a few attempts to get the feel. I would not say I am proficient at it after only three attempts. I would not want to figure this out for the first time near the ground with the windshield full of trees or houses.

I regularly do 180 power off landings from pattern altitude at the downwind for fun. Those are a piece of cake compared to this maneuver.

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