Decision Height on Take Off

sheldon957

sheldon957

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Sheldon957
As pilots, is seems than we worry about our landings the most, but the most dangerous time in flight IMHO is the take off. Many many pilots die when they try to turn back without sufficient altitude and/or skills, and stall the plane.

I was talking to and experimenting with my CFI on my last IFR lesson about Decision Height on Take Off, specifically relating to Altitude minimus when trying to turn back to the airport. In a 172, I personally felt that 600' was a minimum. We did some simulated engine outs and found I could turn around with at least 100' to spare.

Today I came across this excellent article.
http://www.avweb.com/news/pilotlounge/pilots_lounge_121_big_silence_after_takeoff_196805-1.html

The major points I hadn't considered were the steepness of the turn, turning more than 180 degrees, and the different "sight picture" being at low altitudes. I also like the complete take off brief idea.
 
I know that instinct will be there to turn back, but unless I am at TPA, my training has been to just pick the best spot forward. Too many people die trying to turn back....
 
Keep in mind--with no wind-- and anything less than about a 3,500 ft takeoff you will not make the runway turning back from any altitude. Your glide distance is shorter than your climb distance.

In order to successfully turn back you need:
1.) At least 3,500 feet (or a strong wind)
2.) At least 500 feet and you better be a damn good pilot

You better have a good reason to justify a turn back. Make your decision before you take the runway. If you feel that airport justifies a turn back touch the spot on the altimeter that you need to reach to do it. If you don't think about it before hand--consider yourself dead.
 
I think that's going to depend on the plane Jesse. On a cold day with no wind I can be above pattern altitude before 3500 feet when I'm light. August, not gonna happen. Also, if you have a strong wind, you wont have enough runway when you make that turn, you'll go off the end. 500' is probably about right with most fixed gear singles though, and that's my straight ahead/turn back altitude in the Cherokee, I know that's going to change with my Comanche.
 
Jesse & Tdager,

I agree with both of you. I just want to make sure every pilot knows to fight the turn back instinct without sufficent altitude.

Jesse, I also assume you are talking about runway length with the 3500'.
 
EdFred said:
I think that's going to depend on the plane Jesse. On a cold day with no wind I can be above pattern altitude before 3500 feet when I'm light. August, not gonna happen. Also, if you have a strong wind, you wont have enough runway when you make that turn, you'll go off the end. 500' is probably about right with most fixed gear singles though, and that's my straight ahead/turn back altitude in the Cherokee, I know that's going to change with my Comanche.
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It does Ed. He was talking about a 172 in his post. I was replying with regards to a 172. This is a non-issue for me in a reasonably loaded Cherokee 180 or the DA-20. Yes--too strong of a wind will require some creative flying to get it down in time. But no wind, typical 172 performance, and less than 3,500 is always a no go.

The truth of the matter is--you really need a good reason to justify a turn back. There are too many variables in play to do it otherwise.
 
I think the first instinct should be to forget about saving the plane. Save yourself. If more pilots did not try and save the plane and just picked the best chance for self preservation there would be far less fatalities. When I look down I think where is MY best chance for survival.

Dan
 
When I take off, the insurance company owns the airplane. I try to protect lives on the ground, then lives on the airplane, then property on the ground, then the airplane itself, in that order.

My takeoff brief always includes what happens if we have a problem (any problem) during:
  • The takeoff roll
  • The initial climb to MEA (or some arbitrary altitude in VFR where a safe return to the airport is possible)
  • After reaching MEA.
The actions that get taken during the initial climb vary on aircraft type, but in general, in singles and light twins, the primary objective is to come back to earth under control with minimal energy, preferably in an empty area. That may include a turn to the left or right, but generally does not include an attempt to return to the airport.

A briefing, even if you're the only one in the airplane, is an excellent way to commit yourself to specific actions, so there will be no hesitation once the adrenalin spike passes.
 
Turnback technique is critical here. If you pitch to best glide and do 30 degrees of bank, you are going to require a lot more altitude than if you are more aggressive. I practice at 50 degrees of bank and 5 knots over stall speed. Though 60 degrees of bank (or more) would save a few more feet, I find in my Lance that 60 degrees and +5 knots requires too hard a pull on the yoke. Also, you need to put in some "what happened?" delay when you practice.

I am quite conscious of the fact that it's the insurance company's airplane if the engine craps on initial climb, but at the same time I typically fly from urban airports where the airport ground might be the only open space around. And you don't want to end up like the twin Cessna in Los Angeles that skidded through an intersection only seconds before two school buses loaded with kids entered the intersection, one from each side.
 
The thing about takeoff being the most dangerous time is so true, IMHO... I don't care what's wrong: fire, smoke, engine failure, snakes in the plane, parts coming off...I'd rather have it happen while approaching a runway than when leaving one behind. :D I mean, if all hell is breaking loose on your flight, what's the only- and I mean only- tsight that will comfort you? Yes... a runway. :D

I never had an instructor get much into the possibilities of turning around before reaching TPA, or turning around at all, really, during a departure emergency...the advice I heard most was "pick a clear spot ahead and put it down as best you can." What's saddest about those who've bought it trying to make that 180 is that what they feared (making a controlled but scary and probably expensive forced landing with possible injury) was nothing compared to completely losing it and augering in. A departure emergency is no time to base your actions on fear, although it's gotta take some serious willpower to do otherwise. Hope I never find out.

I've certainly though about what decision height and distance might work, and practicing MCA turns, chandelles, etc has given me a little confidence in that department... and I do know for sure what to do once I finally get downwind and need to tighten up the pattern because of my descent rate (that's the easy part).
But my thought as I start the initial climb is always "OK, where do I go if the engine quits right now?", and generally speaking I just keep thinking that all the way to my destination. :D

If I were to consider turning back and I was not at TPA yet, I don't think I'd bother myself trying to figure out if I'm 3500 feet from takeoff or not- I'd probably just look over my shoulder and ask myself if it was do-able. If I was lucky, I'd remember to factor in DA, wind speed and direction, traffic, etc.... let's face it, 99% of the time just blundering ahead as best you can is better for all concerned... there are many things that can go wrong if you try to be masterful when all you really need to do is survive a forced landing without killing anybody on the ground.

I suppose in a light wind or a crosswind, there would be some sense to turning around to land "the wrong way", alongside the runway if traffic makes that necessary. But the key factor seems to be making that first turn safely, which is where most people go wrong. They rarely execute that first turn properly then lose it on the next turn or run out of altitude on downwind- they try to horse the plane around at a high AOA and low airspeed with predictable results.
 
200 ft is the minimum in the glider. highly wind dependent. most i've done it with was about a 12 knot head/tailwind in a schweizer 2-22. that glider does not have particularly powerful airbrakes. we really had to work to get it back down and stopped. of course there is an issue in the glider when you are moving 15 knots down the runway and lose all directional control. brake hard. basically with 12 knots we ended up stopping at the end of the runway and were able to just turn around and hook up to the towplane again. I wouldn't want to try it with any more wind. Nice thing is with stronger winds there will often be runway left ahead of you to land.
 
Another thing to remember is that in the real world of flying, your reactions and reaction time may be critical in whether the turn–back option works out ok. When training or practicing, you are expecting the problem to occur. In fact, you KNOW it will because that is what you and the CFI are doing. Your brain and nerves and muscles and attention are already primed to handle things. You react instantly. And that's ok, if you don't practice and experiment, the first time it comes up will be when it happens for real.

However, in the "for real" scenario, there will almost certainly be a few seconds of either confusion, disbelief, a slight pause in thinking, etc., during which time the airspeed is bleeding off, or even if you lower the nose the direction of travel is away from the runway and the altitude is bleeding off.

Often, if the manuever you are going to perform to get back to the runway is dependent on perfect execution, immediately, under the conditions of the emergency [say, the altitude on upwind at which it occurs, the wind component, etc.], you aren't gonna make it to the runway anyhow. Just keep it in mind....
 
I don't really consider turning back to be and option and never had. Once the runway is gone its gone until I can see that I can make it. Until then other options will have to do so I never really thought much about it let alone attempted it. When you do speak of turning back are you talking about putting it on the fiield (as previously stated it could be your best option in rare occasions) or putting it on the runway you left from? In such a critical situation this might make a difference. From a workload and aircraft performance standpoint, doing a clean 180* turn would be differeint from doing a 215* turn to point the nose back to the departure end then trying to line things up. Just a quick thought.
 
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Here is a video of a 172 trying to make it back to the lift off at a simulated 1000'. It comes up short 1/2 mile each time. So unless you are taking off from a LONG runway, you won't make it. They use a 45 degree turn, and you can hear the stall horn at 65-68.

http://www.veoh.com/videos/v1290093pzFrKyKK

My 600' level I was able to get turned around, but would not have made it even close.
 
TMetzinger said:
When I take off, the insurance company owns the airplane. I try to protect lives on the ground, then lives on the airplane, then property on the ground, then the airplane itself, in that order.

My takeoff brief always includes what happens if we have a problem (any problem) during:
  • The takeoff roll
  • The initial climb to MEA (or some arbitrary altitude in VFR where a safe return to the airport is possible)
  • After reaching MEA.
The actions that get taken during the initial climb vary on aircraft type, but in general, in singles and light twins, the primary objective is to come back to earth under control with minimal energy, preferably in an empty area. That may include a turn to the left or right, but generally does not include an attempt to return to the airport.

A briefing, even if you're the only one in the airplane, is an excellent way to commit yourself to specific actions, so there will be no hesitation once the adrenalin spike passes.
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Amen. I do this too... and I'm ALWAYS carefully checking the engine instruments for any indication of an issue whilst I'm within gliding or return distance to either my departure or any enroute destination.

It's amazing how many pilots, flying out of the same field day after day, have never "put the nose down" after takeoff, 400 AGL, to get an idea of "what's out there". I suggest all try this on their next flight from their home aerodrome if you haven't already. The nose blocks a good deal of your "choices". Pull your power back a little, drop that nose immediately, as you'd have to if you lost your engine, and scope out "what are my options, right here, right now..." Then you'll KNOW what your choices are, instinctively, if it ever goes wrong.

The flip-side to that is being always aware to do the same when arriving at a new airfield... while in the pattern for landing, scope out what your emergency landing choices will be for the departure roll from the same airport...
 
sheldon957 said:
Here is a video of a 172 trying to make it back to the lift off at a simulated 1000'. It comes up short 1/2 mile each time. So unless you are taking off from a LONG runway, you won't make it. They use a 45 degree turn, and you can hear the stall horn at 65-68.

http://www.veoh.com/videos/v1290093pzFrKyKK

My 600' level I was able to get turned around, but would not have made it even close.
Click to expand...
He didn't turn near steep enough. He also was doing it at 1,000 feet. That's too high. There is no way you're going to make it back. Remember--climb distance > glide distance in 172. So by climbing 1000 ft off his "runway" he was placing himself too far from it.

I've done this on the deck in a 172 before from 500 feet. You really need to be on top of your game. I wish I had recorded it on video. Maybe I'll try to get a video of it the next time I have a chance.
 
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rottydaddy said:
But my thought as I start the initial climb is always "OK, where do I go if the engine quits right now?", and generally speaking I just keep thinking that all the way to my destination. :D
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Me too. And I think that's what makes IMC the most rattling to me... is the "what if I lose an engine" while in solid IMC. I need to spend some more time chair flying that scenario. Not being able to look down from 8000' and pick a field and start gliding towards it (or even worse, being down lower while being vectored towards the field and thinking about losing the engine) can be unnerving.

Situational awareness is very important here, obviously. Before moving maps with "Nearest" functionality, I think people were either more aware of their position and the underlying terrain, or they just got lucky. I also think we probably are more dependent on our moving maps and nearest buttons than we should be, and many pilots flying IMC today, if they lost the engine and electrical system at the same time, and thus the GPS, might not have a clue which way to turn to start gliding towards an airport, or barring that, lower/better terrain.

I'd love to hear from the more frequent IFR pilots on this board about how they manage that risk... what's your mental gameplan to deal with an engine failure in a single while IFR?
 
tonycondon said:
200 ft is the minimum in the glider. highly wind dependent. most i've done it with was about a 12 knot head/tailwind in a schweizer 2-22. that glider does not have particularly powerful airbrakes. we really had to work to get it back down and stopped.
Click to expand...

Tony, was this a real rope break, or were you just practicing from 200'?
 
TangoWhiskey said:
Tony, was this a real rope break, or were you just practicing from 200'?
Click to expand...

I believe that there is a requirement for a simulated 200' rope break for the glider ratings. But I could be wrong.
 
We do huge briefings before any departure, consisting largely of what we will and will not abort a t/o for. Above V1, though, we take everything flying, and will battle through a low vis engine failure because we'd need a lot of runway to get the thing down and stopped again. We kind of take for granted our ability to climb on one engine, though. Even without exceeding the engine limits, it has to be a pretty heavy plane or rather warm day for us to not climb. Given a hot and heavy situation, we can just over torque the engine and power out of it to the end of the rudder travel. That's why in the sim, they make us think about the turn back situation.

There's no company policy or written profile for it, and we never really talk about it. So after you've done a couple successful V1 cuts, they give you one with negative autofeather, gear breaker pops so it's stuck down, flaps get welded at 17*, and it's always on a "summer day at LGA." You can cook the good engine right off the side of the airplane then run out of rudder travel and still not climb. Then they set the good engine on fire. Now you have to have the presence of mind to NOT blow the fire bottle and decide whether you're going to try to A) turn around and let down to the runway that's now covered by flog, B) try to find another airport PDQ, or C) ease it down straight ahead. Long story short, I decided I really wouldn't want to be faced with a post-take off engine failure...ever.
 
What Dave Rogers writes is excellent. But I have a number of BFRs back for another who when I quiz them think they can make it from 800 AGL in a 172, 3600 foot runway, 5 knot headwind. But guess what? They've never practiced, and they're back to requiring 1000-1,100 feet two years later.

Pitchy to Vy + 5 for the 45 degree bank turn (which is where you should be when we pull the power), (so chosen that your driving slop doesn't stall you), get the nose DOWN for that, and get in flying shape again.

I shudder to thing where my average PVT ASEL will be trying a 60 degree bank- probably will be a stall spin in 'cause he forgot the ball and the Vs is now Vso x 2.0.

For me, in the Seneca, 200 undergross, 3600 feet, in summer, the DH is 5 feet. We fly at 5 feet on both fans until we get Vyse, then up come the gear and we're going.
 
bbchien said:
For me, in the Seneca, 200 undergross, 3600 feet, in summer, the DH is 5 feet. We fly at 5 feet on both fans until we get Vyse, then up come the gear and we're going.
Click to expand...

Dave S. flies his Baron that way too... it's exhilarating to accelerate down the runway in his plane, watching the end get closer and closer, while he gets his airspeed where he wants it in case one stops turning! :yes: You sure feel safer about the subsequent climb, though, in case one stops turning...
 
Assuming I'm past a useable amount of runway: If the engine does as much as hesitates, I pick a place somewhere close and generally in the direction I'm already going that I KNOW I can get to. THEN if I have time to piddle around, I'll look over my shoulder for the runway while not jepoardizing the planned set down location. If my instinctive reaction to the runway is anything other than "no problem, easy turn, plenty of altitude, do it," the runway is instantly declared non-existent and I'll proceed with plan #1. I was trained to the point that it's instinct for the runway to be option #last unless it's readily available and within my gliding energy cone.

The general concept is low=straight ahead and as altitude increases, the available heading change off straight ahead increases until it becomes a full circle.
 
bbchien said:
What Dave Rogers writes is excellent. But I have a number of BFRs back for another who when I quiz them think they can make it from 800 AGL in a 172, 3600 foot runway, 5 knot headwind. But guess what? They've never practiced, and they're back to requiring 1000-1,100 feet two years later.
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And if they actually tried it...1,100 feet, summer day, 3,600 ft runway, with a 5 knot headwind..They'd find themselves crashing before the airport.
 
TangoWhiskey said:
It's amazing how many pilots, flying out of the same field day after day, have never "put the nose down" after takeoff, 400 AGL, to get an idea of "what's out there". I suggest all try this on their next flight from their home aerodrome if you haven't already. The nose blocks a good deal of your "choices". Pull your power back a little, drop that nose immediately, as you'd have to if you lost your engine, and scope out "what are my options, right here, right now..." Then you'll KNOW what your choices are, instinctively, if it ever goes wrong.
Click to expand...

KGTG I use RWY 30 most of the time, County Road F slight turn to the right lines you right up anything over 100' AGL will make it. If there is someone on the road they will most likely tow you back to the airport.

Dan
 
If you're going to learn this maneuver, learn it at 2000 AGL or more, and master it there before you try it right off a runway.
 
Beech Pilot Proficiency Program used to teach this and it is my understanding they stopped because of a couple incidents. The folks I know, now teach it with a hard ceiling below. In my A-36, I just looked about 30 degrees left or right for a landing area until above 600 AGL unless there was another airport or known forced landing area in the flight path (not normally the case). From there until my glide range improved, 90 degrees left or right, but ahead first. Where I depart from (KADS) is urban and the best alternates seem to be a major highway north or rail road track south. Not great choices. I did a cruise climb in the A-36 as in the Baron.

At SIMCOM last year, losing one fan after Vyse, caused us to gently turn 30 degrees right and fly outbound one minute while climbing above Vyse. Then, a standard degree turn left lined one up pretty close to the departure runway opposite direction. That was the quickest return to the departure airport. If winds or other factors didn't allow that, we'd do standard turn for the traffic pattern, but never climb up to TPA unless necessary for obstacle clearance. We could stay below a lot of weather that way and not have to be vectored back around for an instrument approach (we did some of these as low as 300 feet above obstacles (which circle to land minima can be). Of course, if departing at minimums, this wouldn't work and we had the instruments dialed in to get vectored back for an instrument approach.

Of couse, I'm adding instrument turnbacks to what was VFR procedures.

Best,

Dave
 
We (or at least I and several other safety concious CFI-G's) require successful "simulated" tow failure practice before solo flight. We "simulate" this by pulling the release somewhere between 200 and 300 feet on initial climbout. I am always very careful to be right on top of the current situation with regards to traffic, wind, climb rate, and location before even thingking about it. Its not just about rope breaks. What if the towplanes engine quits, or simply loses a cylinder, or a multitude of other bad things. But yes, for the training we pull the release and the student executes a turnaround and downwind landing. This manuever is HEAVILY briefed the first time we do it, and from there on out the student should expect it at any time. Key points are airspeed control and a brisk turn with tight coordination, usually followed by airbrakes/slip as needed and a landing. You can bet that I am closely following the students every move from the moment i pull the release to touchdown cause there just isn't much margin for error. I also always have at least 1 or 2 other options depending on the students reaction time. We have many grass infields and a whole other runway with parallel taxiways all over the place at Ames so we have a lot of choice.

When I was training it usually took me about 5 minutes to recover from performing one of these "simulations"
 
tonycondon said:
When I was training it usually took me about 5 minutes to recover from performing one of these "simulations"
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:hairraise:I think I'd want to try that in the simulator a few times before doing it in the real plane! :D
 
From my readings, it appears that one of the biggest mistakes in flying, is thinking that you can turn around on takeoff and make the field. I was reading a book about WWI pilots, and the author referred to a pilot who tried to turn around and land back at the field, as being an inexperienced pilot. He said that an experienced pilot would not try to turn back. By the way, the pilot put her into the ground. For my part, better pilots than me have made that mistake, and I don't intend to. I figure that in real life, if you pull it off, you are lucky, and if you don't, your dead. Every time I take off, I'm looking for somewhere to put it down, just for practice.
 
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Maxmosbey said:
From my readings, it appears that one of the biggest mistakes in flying, is thinking that you can turn around on takeoff and make the field.
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With enough energy (potential plus kinetic) and the proper technique, it is not a mistake. The problem is that a lot of pilots don't know how much energy they need or the proper technique to use, and those folks are likely to prang it if they try it. For them, the First Rule of Italian Driving ("What's-a behind me is not important," Bail and Capetanos, 1976) would apply -- put the airport behind you out of your mind, find the best landing spot in front of you, and put it there, as Max suggested. If you don't want to be one of them, read Rogers' paper, get a good instructor, and learn/practice the manuever at a safe altitude until you have the technique down and know the minimum energy required in your plane.
 
TangoWhiskey said:
Amen. I do this too... and I'm ALWAYS carefully checking the engine instruments for any indication of an issue whilst I'm within gliding or return distance to either my departure or any enroute destination.

It's amazing how many pilots, flying out of the same field day after day, have never "put the nose down" after takeoff, 400 AGL, to get an idea of "what's out there". I suggest all try this on their next flight from their home aerodrome if you haven't already. The nose blocks a good deal of your "choices". Pull your power back a little, drop that nose immediately, as you'd have to if you lost your engine, and scope out "what are my options, right here, right now..." Then you'll KNOW what your choices are, instinctively, if it ever goes wrong.

The flip-side to that is being always aware to do the same when arriving at a new airfield... while in the pattern for landing, scope out what your emergency landing choices will be for the departure roll from the same airport...
Click to expand...

Troy, I did this years ago leaving my home drome on rwy 2 and swore I'd never do it again. The only thing in front of me were the ridges and river. :hairraise: Not a fun option. If I had an engine failure on take off from rwy 2 there really isn't a good option if you can't make it back except deciding on which ridge to try and land on. It's surprising what conditions you can grow accustomed.
 
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