Pilots: Engine failure, return

[SunDog]

Pilots: looking for objective observations, thoughts, and experience, related to attempting to turn back to the runway after engine failure on takeoff.  Most particularly interested in C-172 performance. I'm finding the sims don't match the actual performance closely.  I'm seeing, real world,  it takes about 800 feet, 45 degrees of bank, and a hefty push (real hefty) to pitch to best glide.  This matches pretty well with some published stuff I've found.

Again, not looking for a debate or dogma - working on refining simulation accuracy, based on the performance of the real airplane.  Experiments at altitude are pretty tame; the visual clues are more dramatic in actual practice, especially with any crosswind.

If you have another technique, could you describe it, add your thoughts/reasoning? Turn strategy, bank angles, target airspeed? Very interested in use of flaps, as well. So far, I've been doing it no-flap; looking to expand on flap use, progressively.  Just looking to get back over the threshold, wings level, MCAS.

[SarDragon]

That came up when I was taking real lessons, and my instructors all said, "never turn around. Crash straight ahead."

[a2capt]

I've made a 270 degree turn in practice conditions, with about just over 300 feet of lost altitude.

Pulling the engine while climbing in the middle of Vx and Vy, waiting 5 seconds and then responding with best glide speed and a 45 degree bank.

[Check Pilot/Tow Pilot]

If this is for a briefing, I created a 45 minute PowerPoint and followed it up with an X-Plane Sim and had aircrew attempt the landing from 300 to 500 feet.

I can share that if there is any interest.

[Robert Hartigan]

Here is a great article on the subject. I used to think I could make it back if I just had enough altitude. Tommy Wiklind presents the math and I am now a land straight ahead pilot!

http://tommywiklind.com/aviation/EngineOut.html

[SunDog]

Yes, thanks, seen some other articles like that, as well.  Peter Garrison had a good analysis a few years back, as well.  They usually turn out to be more pessimistic than I'm seeing in actual testing, but are solid reference.  Truthfully, if you figure the G forces in, touching down level, minimum speed, you can literally walk away from a forced landing in the average driveway. I think that's why all the advice over the years has been to crash straight ahead. Makes sense, to a point. YMMV.

I'm looking to improve the fidelity of simulation, which isn't too good near (and beyond) the edges of the
C-172 envelope. Basically, the sims don't reflect the actual performance in extreme/unusual attitudes. What I'm seeing in the real airplane isn't what the sims are showing.

The teardrop (potato, more accuratley in real world) looks to be the best turn strategy, but I ain't the ace of the base, so looking to hear from other folks on technique. The visual clues are fairly dramatic when trying this in the pattern, as opposed to doing it at altitude. It was a non-event at 3000 AGL; got my attention more forcibly the first few times at 800'

[PHall]

Trying to turn back after engine failure immediately after takeoff has killed many a pilot.
You're at the bad corner of the envelope (low and slow) so you usually don't have much altitude, if any,  to trade for airspeed to deal with the increased stall speed from the turn.
Which is why most instructors teach the land straight ahead technique these days.

[SunDog]

Right, I think that's what we've all heard over the years - I'm looking more for specific experience and techniques for turning back, from others who have experimented with doing so; what worked better, what didn't.

The sims aren't too useful, as the fidelity isn't there, once you leave the confines of "normal" operations. Clearly, there is an altitude from which it makes sense to turn back on a given day, depending on wind, runway environment, etc.

So I'm working on that a bit, and also translating it to accurate sim depiction.  The consensus seems to be a fairly steep turn, into the x-wind, tear-dropping back at best glide, for a downwind landing. 800 AGL or above (wind dependent) seems to be doable, with low margin for delay, or airspeed devay.

[PHall]

It's the steep turn that will kill ya.  The stall speed increase of a 45 degree bank or even a 60 degree bank with no way to increase your airspeed will usually result in a nice deep stall.
A deep stall like that close to the ground (i.e. less then 1000 feet agl) with no way to increase your airspeed is usually not survivable.

[SunDog]

I've made a 270 degree turn in practice conditions, with about just over 300 feet of lost altitude.

Pulling the engine while climbing in the middle of Vx and Vy, waiting 5 seconds and then responding with best glide speed and a 45 degree bank.

Sounds like a very good figure for altitude loss - leaves one more turn to complete, and the ground to cover back to the threshold. I'm seeing more than 180 required, less than 270, when turning slightly into the x-wind  (20 degrees?) and then turning 180 very quickly (10 seconds or so). Hopefully leaves about 20 degrees or so more of turn to get the nose pointed at the threshold. Wind and YMMV. And so many other variables, of course - how far did you get from the runway before reaching 800 feet? DA, GW, rwy length all figure into that., too.

Big, big deal (to me, anyway)  was recognizing the very large pitch changed required to get/keep best glide after pulling power.

[SunDog]

It's the steep turn that will kill ya.  The stall speed increase of a 45 degree bank or even a 60 degree bank with no way to increase your airspeed will usually result in a nice deep stall.
A deep stall like that close to the ground (i.e. less then 1000 feet agl) with no way to increase your airspeed is usually not survivable.

Best glide will keep you below the stall AOA with 45 degrees of bank.  Gotta push to best glide, then quickly trim for it.  Hard discipline is to fly that speed, bank angle, and ignore the ground proximity. If it turns to poop, roll wings level, settle and slow, touch down like you would have crashing straight ahead. Key is control the AOA. You're spot on about stalling out of a 45 degree bank below 800 AGL - your recovery would have to be with perfect technique, which wasn't evident in the first place. . .

Understand, I'm not advocating either way.  Not sure I've made up my own mind. Doing this a few times, I can say the relative motion, close to the ground, is a distractor.  Need a few reps to desensitive to that. If it comes to it, I think now I'd commit to one or the other, immediatley, and stick with it. Either case, my priority is keep the AOA  below stall, have first impact wings level with the horn blaring.

Let's assume what's out in front looks real bad -water, trees, real bad terrain - and we have "X" feet of altitude - whats the best way to manage our energy to get back to, or near, the rwy environment?

[Cliff_Chambliss]

If the engine quits on takeoff and I am below 800 ft AGL the insurance company now owns the airplane and I am looking for the flattest softest place  not more tha 90 degrees left or right of my course.  Yes, there are exceptions.  For instance if at an airport with multiple runways and I can make any runway open or closed, or taxiway, then that becomes my destination.  There is no one set rule for every airport runway.  We'll this is wrong, there is one hard rule. Never sacrifice the crew while trying to save the airplane.

I have all my students get familiar with the airport environment and brief the takeoff before we enter the runway.  For example when flying off runway 36 at Birmingham, Al.:  we are departing runway 36 full length.  Engine failure or emergency below 500 feet land straight ahead.  Emergency 400 to 800 AGL, left turn and land intersecting runway 24.  800 or higher right turn for runway 24. 

Pilots need to really look at the airport and surrounding areas as there may be limited opportunities available for a successful off airport landing. 

[SunDog]

I'm looking at a single runway scenario; to get back to (or near) the departure end of the one you just left; Do you have criteria and technique for doing so worked out?  I've worked out what I described in my previous posts. . .does it strike you as the best way to get it done? Appreciate any insights in attacking the problem.

It doesn't seem like a lot of CAP pilots hit this site - not much in the way of aviation posts happening here. . .

[Check Pilot/Tow Pilot]

I'm looking at a single runway scenario; to get back to (or near) the departure end of the one you just left; Do you have criteria and technique for doing so worked out?  I've worked out what I described in my previous posts. . .does it strike you as the best way to get it done? Appreciate any insights in attacking the problem.

It doesn't seem like a lot of CAP pilots hit this site - not much in the way of aviation posts happening here. . .

I think there are a lot of lurker pilots.

[SunDog]

I imagine so; a lot of the other topics wouldn't draw a pilot crowd much. . .

On topic, experimenting with the return in a CAP 172 is a bit more of a sporty course,  as opposed to doing it with an AOA indicator equipped airplane. 

[Cliff_Chambliss]

I'm looking at a single runway scenario; to get back to (or near) the departure end of the one you just left; Do you have criteria and technique for doing so worked out?  I've worked out what I described in my previous posts. . .does it strike you as the best way to get it done? Appreciate any insights in attacking the problem.

It doesn't seem like a lot of CAP pilots hit this site - not much in the way of aviation posts happening here. . .

Well, what does the terrain surrounding the airport look like?  what options are available?  How long is the runway?  How much wind?  You should not try to make a one size fits all emergency procedure.  Sure you can have the basics such as immediate pitch down to prevent shall,  less then 200 ft take whatever is ahead of you.  200-400 options up to 45 degrees either side of the nose, 400-600 ft options to 90 degrees and so on. 

Barry Schiff in his book "The Proficient Pilot" published in 1980 has an article addressing this situation.  In his article he had a Cessna 172 loaded to max gross weight and attempted turn backs to the runway following a simulated engine failure.  Power was pulled and a four second wait before anything was done and the the maneuver performed at bank angles of 30, 45, 60, and 75 degrees.   Generally, the shallower the bank the less likely the manuever would be successful (At 30 degrees the airplane lost 400' for a 180 degree turn.  Hoever at 75 degrees of bank the airplane only gave up 210 ft of altitude for a 180 degree turn)..  The best possibilities were at bank angles of 60 and 75 degrees, top rudder  and airspeed just above stall,  but here the tradeoff is you are right at the very edge of a stall and should anything go wrong the reslt will be non-survivable.  Not a maneuver to be performed without lots of current practice at altitude.

Barry Schiff has two books, "The Profcient Pilot" and  "The Proficient Pilot II".  Both books are a series of insightful and thought provoking articles for pilots.

[SunDog]

Maybe I didn't articulate my aims very well; this research isn't intended for a specific runway or for developing a generic procedure. Wanted to expose my conclusions from my experiments on turning back, get some input, ideas, and critiques. Looking for techniques hints, things I may have overlooked, etc. Thanks for the Barry Schiff reference, and the specifics on bank angles.

Clearly, wind matters, understood.  The reversal angle of bank is a compromise between stall margin and getting through the turn quickly. CAP 172s don't have AOA indicators, so you're stuck with airspeed indication as the only clue to stall margin. In the CAP plane, I've limited the reversal to 45 degrees. With an AOA equipeed airplane, I'm a lot more comfortable with much steeper angles down low. I have pulled to stall in steeper angles at altitude in the CAP 172s, and the aerodynamic warning, and the horn, give adequate warning, as long as the pull isn't too rapid.

Have found the siim's fidelity to be poor, except for vanilla manuveurs.  Doing the teardrop reversal in the sims doesn't match the airplane real-life performance in this (and other) situations.

Mucking about with the various combination takes a lot of time, so haven't got around to seeing how flap use impacts the performance. Obviously the stall margin is improved, but need to see how flaps affect altitude loss.

[Cliff_Chambliss]

If you want, I'll scan Barry's column and email it to you.  I just hit a couple of points on a several page item.

If you can find a copy of Barry Schiff's books there is a lot of good information.

Respectfully, you state you are comfortable with steep bank angles down low and the 172 gives adequate warning as long as you do not pull too hard.  I would guess that your experimentation so far has been with only one or two persons on board.  As docile as the 172 is loaded to the front of the cg envelope it can bite really hard when the cg shifts to the rear.  That third and fourth person in the rear seat can change the handling a lot. 
  Also, it 's real easy to not pull hard when training or practicing but in the heat of the moment it can be way too easy to over pull.  As an aviation safety officer in a previous life we used to say most accidents happened when something went wrong and the pilot did too many things too fast followed by too few things too slow. Please be careful.

[SunDog]

Yes, thanks, that would be great. I'll shop for the books, as well.  I hear you on yanking and banking under stress, and the need to be deliberate and disciplined. AOA is a great tool for a tunnel-visioned pilot in a low-stall margin situation. I am keeping it at altitude (or reduced bank angle) in the non-AOA equipped airplanes.

CG! Dang! The CG consideration had escaped me; I don't recall EVER doing a stall series with anyone in the back, now that you mention it.  Maybe with one other person, right seat, on a check ride or getting dual; but usually alone.  I have to look again at the sim GW and CG parameters, see what those presumptions are - you may be onto why the sims differ from the real-world performance I'm seeing. 

Yeah, GW doesn't affect stall all that much, but CG would sure impact pitch rate and response, of course! Thanks!

[JeffDG]

If you really want to check the fidelity of a simulation, then get in a plane and try it...not literally from the runway, mind you, but pick an altitude, say 2,000' AGL.

Start a climb at Vy, at say +500' pull the engine to idle and get turned around.  You can use a handheld GPS to simulate the "runway" that you want to get back to.  See how much altitude loss happens before you're back lined up.

There are other factors that mess with you too...wind is a big one.