Possible turn

[Stephen]

Hi MS'ers. For BFR fodder and general knowledge, I had a question that I would like to get tap some collective MS wisdom on: How high do you feel you need to get after takeoff before you would consider turning back in the event of an engine failure, and have you practiced idle 180 procedures/what are your experiences/thoughts/technique/considerations?

Thanks in advance for your thoughts, 

Stephen

[Ragsf15e]

1 hour ago, Stephen said:

Hi MS'ers. For BFR fodder and general knowledge, I had a question that I would like to get tap some collective MS wisdom on: How high do you feel you need to get after takeoff before you would consider turning back in the event of an engine failure, and have you practiced idle 180 procedures/what are your experiences/thoughts/technique/considerations?

Thanks in advance for your thoughts, 

Stephen

I have practiced, I use 1000’.  During practice at higher altitude I was successful at close to 700-800’, but with zero margin.  I tried to recreate a Vy climb, 3”, reaction time, and 270/90 turn to align with runway.  Gear and flaps were up.  I don’t think i messed with the gear at the end.  
 

It’s definitely worth doing a few times at 4 or 5000’.  You will need at least 45 degree bank turn.  60 degrees might actually work better but I think doing that very low to the ground is going to be pretty uncomfortable.

Key is remembering that the stall is based on AOA, not airspeed.  You can be stalled (or not) at any attitude or airspeed.  It just depends on how much AOA you’re demanding.  So bank it up hard, pull close to the stall, keep your nose down and your speed around Vg or maybe slightly higher.  See what she feels like.  Enjoy!

Accelerated stalls (say level, 45 degrees bank) might be nice to practice first.  Pull to feel the buffet so you know how far you can go.  If you pull all the way through and stall you get a face full of ground.

[Paul_Havelka]

My CFI has me practice pretty consistently as soon as I reach pattern altitude.  I have it down, even when he surprises me, that as soon as I think about turning crosswind I can make it back to the runway.

[PT20J]

Hey Paul @Pmaxwell, how high was Don when the engine quit? I remember his clunk, chirp description of putting the gear down at the last moment, but I don't recall how high he said he was when it quit.

Skip

[Stephen]

Thanks @Ragsf15e 

[Bob - S50]

I haven't done one for real, but at altitude I set up my typical climb in our J of 100 KIAS.  At an altitude I picked for convenience I pulled the power to idle, lowered the nose to maintain 90 KIAS, rolled into a 45 degree bank, maintained that bank and 90 KIAS by adjusting back pressure, and did a 360.  I lost 400'.  I figure a 360 degree turn would lose about as much as a 260/80.  I then added a 50% safety margin, so I figure I would give it a try from about 600' AGL or higher.

There are a few articles out there about the impossible turn, and at least one of them points out that 45 degrees of bank is the optimum bank angle.  Less bank will result in lower sink rate but will take longer to turn around and place you further from the runway after 180 degrees of turn.  More bank will keep you in tighter but will result in a higher sink rate and a higher chance of an accelerated stall.  If you think in terms of SIN and COS of angles, the sum of the two is maximum at 45 degrees of bank.  At 30 or 60 degrees of bank the total is .5 + .866 = 1.366.  At 45 degrees of bank it's .707 + .707 = 1.414.  So you get the most bank for the buck at 45 degrees.

[Seth]

Bob Kromer talked about this at length at Mooney Summit III or IV. Climb to altitude as fast as possible so you can make the impossible turn if needed. Once you get to 1000 feet, then nose over into a more cruise climb configuration. That way you are not two miles away when your engine starts stuttering and not quite at 1000 feet. 

I rotate, give a little nose over to allow the airplane to accelerate, and then pitch up and climb out. As soon as there's no usable runway left, gear up. I usually raise flaps passing 600 and cruise climb at 1000 nosing over to pick up some good speed in the Missile. Again, this way if needed I can make it back.

I have done the 180 degree turn and back at altitude lined up over an airfield at 3000 feet (climbing to 4000 feet) and "cut" the power for the turnback. I can make it from 1000 pretty consistently and have made it from as low as 800. I usually turn into the wind during the turn if there's a crosswind to allow the crosswind to push me back to centerline requiring less of a final line up turn.

I'll tell you, in my 135 work in the Cirrus SR22, she may sink faster than a Piper Arrow - and you have to keep her at 80 knots or better with no power on final or you lose elevator authority and really slam her in (anything below about 78 kias.  If you are at 600 feet in a Cirrus, or are right at 1000 feet, pop the chute, don't try the turn. 

We are spoiled with the wing and aerodynamic affinity of our Mooney's.

 

-Seth

 

 

[Stephen]

22 minutes ago, Seth said:

I rotate, give a little nose over to allow the airplane to accelerate, and then pitch up and climb out. As soon as there's no usable runway left, gear up. I usually raise flaps passing 600 and cruise climb at 1000 nosing over to pick up some good speed in the Missile. Again, this way if needed I can make it back.

I have done the 180 degree turn and back at altitude lined up over an airfield at 3000 feet (climbing to 4000 feet) and "cut" the power for the turnback. I can make it from 1000 pretty consistently and have made it from as low as 800. I usually turn into the wind during the turn if there's a crosswind to allow the crosswind to push me back to centerline requiring less of a final line up turn.

 

 

-Seth

 

 

Thanks Seth, great breakdown

[aviatoreb]

1 hour ago, Seth said:

Bob Kromer talked about this at length at Mooney Summit III or IV. Climb to altitude as fast as possible so you can make the impossible turn if needed. Once you get to 1000 feet, then nose over into a more cruise climb configuration. That way you are not two miles away when your engine starts stuttering and not quite at 1000 feet. 

I rotate, give a little nose over to allow the airplane to accelerate, and then pitch up and climb out. As soon as there's no usable runway left, gear up. I usually raise flaps passing 600 and cruise climb at 1000 nosing over to pick up some good speed in the Missile. Again, this way if needed I can make it back.

I have done the 180 degree turn and back at altitude lined up over an airfield at 3000 feet (climbing to 4000 feet) and "cut" the power for the turnback. I can make it from 1000 pretty consistently and have made it from as low as 800. I usually turn into the wind during the turn if there's a crosswind to allow the crosswind to push me back to centerline requiring less of a final line up turn.

I'll tell you, in my 135 work in the Cirrus SR22, she may sink faster than a Piper Arrow - and you have to keep her at 80 knots or better with no power on final or you lose elevator authority and really slam her in (anything below about 78 kias.  If you are at 600 feet in a Cirrus, or are right at 1000 feet, pop the chute, don't try the turn. 

We are spoiled with the wing and aerodynamic affinity of our Mooney's.

 

-Seth

 

 

I have thought a lot over some years about the 1000 magic number that is called out as the sufficient altitude for a turn back to the runway.  And good practice is before take off roll, to file away that specific altitude and call it out once passed since that is when turn back to runway is plausible.

But depending on what is ahead, we might still want to partially turn back if almost at 1000ft.  I.e. what if in a city environment?  Straight ahead might be quite bad and the departure airport might be a large extensive environment with several runways and maybe lots of grass between runways.  Maybe 130 degree or a 140 degree or 150 degree turn back might be possible with an "off field" landing somewhere in the grass of the field.  So maybe we can do something with 700 or 800 ft?  This is the kind of thing to think about and compute before you turn the engine on.

E

[carusoam]

Practice, practice, practice!

in real life we/MS have lost more to engine out maneuvering then we have to landing straight ahead...

real life is tough... it sometimes  includes some winds and trees... It always includes the ground...

sometimes it is friendly with open fields and cross runways...

Sometimes you are fully loaded and climbing slowly...

 

Some times you prepare in advance by offsetting your departure...

Sometimes you have gobs of excess power....

Some times your pre-thought plan includes various fields for where to go with the energy level you have...

Find the video of somebody doing this for real... the stall horn keeps coming on... the end result was a success...

 

Plan A: Land straight ahead...

Step 1: push, light in the seat...  you have now survived the first step and have Earned a few seconds to decide the next step...

Nice to have: AOAi...

PP thoughts only... not a CFI...

-a-

[Ragsf15e]

12 minutes ago, aviatoreb said:

I have thought a lot over some years about the 1000 magic number that is called out as the sufficient altitude for a turn back to the runway.  And good practice is before take off roll, to file away that specific altitude and call it out once passed since that is when turn back to runway is plausible.

But depending on what is ahead, we might still want to partially turn back if almost at 1000ft.  I.e. what if in a city environment?  Straight ahead might be quite bad and the departure airport might be a large extensive environment with several runways and maybe lots of grass between runways.  Maybe 130 degree or a 140 degree or 150 degree turn back might be possible with an "off field" landing somewhere in the grass of the field.  So maybe we can do something with 700 or 800 ft?  This is the kind of thing to think about and compute before you turn the engine on.

E

Definitely.  It depends.  Each airport/runway has its own best option/altitude.  Having some very basic numbers in mind that should work anywhere is a good starting point.

also, once you turn crosswind, you can do it much lower.  It may be hard to lineup with the runway since you’re potentially more offset but much of the turn is out of the way.

[Skates97]

I practiced it with my CFI and with 700' it is doable but that was knowing it was coming. With the startle factor and reaction time I don't think that is totally realistic for me, although if I am constantly looking for it I think 800' is doable in my plane for me. Practice shows that you are looking at a lot of ground as you come around through the turn and make sure to keep a constant eye on both your bank and airspeed.

There are a few things I try to recite out loud before every take-off. For the emergency landing option if it is a new airport to me then I try to find a place using Google maps satellite view but if not then I tell myself below "XXX" altitude I am looking for a place in front of me.

1. Field elevation / altitude I think I can turn back / pattern altitude
2. When I should be airborne / If not pulling power and stopping straight ahead
3. Best landing option if problems happen when out of runway and too low to turn

For KFUL where I'm based out of I'm typically taking off on 24, so it is:

1. "Field is at 96', I can think of making a turn back at 896, pattern altitude is 1096"
2. "Should be off the ground by Charlie, if not I am stopping straight ahead"
3. "If there are problems just after take off my best choice is Commonwealth" (Not a lot of good options from KFUL but it is a street sort-of aligned with the runway)

Once I begin the roll I call out in the air and passing my decision point, ie: "We are flying and there goes Charlie." After that I try to count off the altitude, "There's 400, there's 500', there's 900 we can turn back if needed," etc...

[Yetti]

Done a partial power one.  don't want to do one again.

Things you should practice in BFR - At altitude set up for take off full power.   have instructor cut throttle.  Push over.  Needs to become muscle memory.  It needs to be fast.

 

 

Write up is here:

 

[Yetti]

I think also being proficient in Power off 180 is a requirement for high performance aircraft.    You spend more time maneuvering close to the ground at a lower speed.

You need to be able to fly the plane by feel.  things need to be automatic.  Best example is they say it takes two years learn to ride a motorcycle.  When you are downshifting while stopping without thinking then you are doing things automatically.

There is not alot of time to look at gauges when the ground in close.  Most of your time is calculating distance to ground vs speed vs. glide path.

Edited October 30, 2020 by Yetti

[MikeOH]

I'm with Rags on the 1000 feet.  I think 'heat of the moment', startle factor, other variables.  I practice power-off 180s frequently and that's the number for consistently getting there (wind effects).

I've also recently revised my gear-up policy.  I used to be in the camp of leaving the gear-down until out of usable runway, but I've decided I'd rather have the altitude.  If it quits I've accepted it's the insurance company's plane anyway, and skidding to a stop before the fence is more likely than stopping with the gear down.

[PT20J]

I've tried this in a number of airplanes (including a very draggy Beaver on floats) and they can all do it from 1000'. Success below that depends on a lot of variables. My technique is to retract the gear at positive rate, retract the flaps when clear of obstacles and continue accelerating to cruise climb.

https://www.advancedpilot.com/articles.php?action=article&articleid=1842

Skip

[Pmaxwell]

7 hours ago, PT20J said:

Hey Paul @Pmaxwell, how high was Don when the engine quit? I remember his clunk, chirp description of putting the gear down at the last moment, but I don't recall how high he said he was when it quit.

Skip

About 600 feet. He turned 45 degrees and landed on the other runway. 

[EricJ]

1 hour ago, MikeOH said:

I'm with Rags on the 1000 feet.  I think 'heat of the moment', startle factor, other variables.  I practice power-off 180s frequently and that's the number for consistently getting there (wind effects).

I've also recently revised my gear-up policy.  I used to be in the camp of leaving the gear-down until out of usable runway, but I've decided I'd rather have the altitude.  If it quits I've accepted it's the insurance company's plane anyway, and skidding to a stop before the fence is more likely than stopping with the gear down.

When I did my first check-out in my airplane the CFI had me do some power off 180s from pattern altitude on downwind to the runway, and the point was well made that you need to start turning right away to make it.   So the 1000' feet seems consistent from that standpoint, too.

When I flew an Arrow, that takes forever to get the gear up or down, I waited to bring the gear up since once it started cycling up it was going to be a long time to get it back down again if need be.   In a Mooney, even with electric gear, the cycle time is short enough that I've not really seen a reason to not bring it up as soon as positive rate is achieved.    I had an engine failure on takeoff where it failed just as the gear finished cycling up and getting the gear back down was straightforward and probably the least exciting part of the event.

[Immelman]

The altitude AGL is one factor, but the climb gradient to get there quite another.  You could practice this maneuver from sea level, solo, and say "boy, that wasn't so bad". Try again with a full airplane, hot, high, or both.... To neglect climb gradient in thinking about this scenario is quite hazardous.

What affects climb gradient?

- Density altitude

- Wind

- Weight

 

[jlunseth]

1000' here also. Now, at my home field it would depend on which runway I used for takeoff. Some of them provide no good choices. If there were a choice between straight ahead into the houses or try a turn of some kind and at least get into a lake or the approach lights or even thread the trees, its the lesser of two weevils as Capt. Aubrey would say.

[Yetti]

Throwing in a couple more things.  Making the field vs. making the runway.  If you could only tell the engine at what attitude to quit at.   I played in MS flight sim and the 172.   the hardest things are going to be.   Excellent execution of a 45 degree bank turn while looking at a windscreen full of earth.    Most people are not ready for either of those two realities.    Good power off 180 discussion. 

 

[steingar]

I usually take off to the West. In reality I don't have to make it to the runway, I just have to get to the farm next to the runway.  I'd probably do it at 700 feet unless there wasn't much wind.  Thing is if I can get the 180 and get it pointed at the farm I'm home free.  Landing in neighborhoods, which is my other alternative, is going to hurt. Taking off to the East I have to make it back to the airport.  Good news is we have parallel runways, so I only have to do a 180, not a 270.

[kpaul]

One of the most important things to take into consideration is wind direction.  You have to make your turn INTO the wind.  

1000' should be doable, with practice 800' is practical. DA and weight will change the altitude required.

Used to practice these often when flying PC-12s.  In a heavy weight PC-12 you needed 800 AGL in a light weight one 500 AGL was easy and actually required a slip to make the runway.

[Bob - S50]

Another consideration, and I cannot take credit for this, I've just read it somewhere.  If you are really worried about the engine quitting on every flight, AND you are flying out of an uncontrolled airport, THEN you might consider making a 45 degree turn once safely airborne.  That way, when the engine actually does quit you won't need a 260/80 turn to get back to the airport.  You might need as little as a single 135 225 degree turn.  Plus, by turning 45 degrees to create turning room you will also reduce your distance along the extended centerline by about 30%.

Edited October 30, 2020 by Bob - S50
Can't do math

[Stephen]

Thanks guys, great discussion. I've thought about the offset Bob suggested after takeoff. The offset, presumably should be downwind so you can turn up-wind in the event of a failure. That said, if the offset turn is downwind, it will carry you away from the runway more quickly and you will be fighting the wind (albeit holding airspeed) to get back. Interesting thought though. If during a crosswind takeoff, if you crab a bit into the wind you are also already pre-oriented in the upwind direction and have some varying degree of turn angle reduction in the event of a turn-back. I was looking at a youtube video and he indicated that his experimentation seems to indicate that the 60 deg vs 45 degree actually results in less altitude loss. Obviously with 60 or more degrees it becomes increasingly *essential to push to maintain airspeed* and avoid loading up the airplane with excess AoA. At 5:16 in the video it gives a pretty good sense of the windshield full of terra firma effect: