Tips, ideas for judging off-field landing distances?

Lndwarrior

Lndwarrior

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I've been flying for a long time and I practice emergency procedures quite a bit, but I totally suck at guessing off-field landing distances.

To be clear, your engine failed and you need to pick a suitable landing spot (assuming one is available).

I know I can land and stop my plane in 800 feet (assuming no vertical obstacle on approach) . So my first choice is to pick a field that's at least this long. Yet, when I'm up at 3,000 or 4000 agl or higher I have a hard time estimating this distance.

My concern is that I might pass up a perfectly acceptable site, just because it may appear too short. I've tried visually trying to figure this out but I find my brain just does not process this as easily as I would like.

Most of my flying is hilly, less-populated areas with few roads.

I'm hoping someone has some rule-of-thumb way of quickly estimating distance. Other tips?

30 years of flying has not helped at all with this particular challenge.

I just watched a video of a guy who crashed and killed his passenger. Afterwards he visited the site and realized there were much better landings options that he could have used, that in the air he thought were too short. This is what got me thinking seriously about this.
 
Go up to 3000 and overfly a known length. Now remember how long that looks. Make a couple marks on something if you cant remember how it looks. At 4000 it will look 1/3 smaller at 2000 it will look 50% bigger.
 
Look at the space between the threshold and the 1000 ft markers while overflying the airport at various altitudes and different distances/angles? Use your hand or fingers as a sighting tool for reference? Just some things to try. Let us know what you find out!
 
Lndwarrior said:
My concern is that I might pass up a perfectly acceptable site, just because it may appear too short.
Click to expand...
The absolute length of the short site is one thing, but you also have to consider what longer site has to offer. Something that's flat but a little short might be preferable to something long and rocky. Another thing to consider is what's at the end of the shorter site. It might be worthwhile to absorb the crash energy by ripping off the wings during deceleration.

And then there's the treetop option.
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Video shows plane crashing into trees on Swan's Island

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Lndwarrior said:
I've been flying for a long time and I practice emergency procedures quite a bit, but I totally suck at guessing off-field landing distances.

To be clear, your engine failed and you need to pick a suitable landing spot (assuming one is available).

I know I can land and stop my plane in 800 feet (assuming no vertical obstacle on approach) . So my first choice is to pick a field that's at least this long. Yet, when I'm up at 3,000 or 4000 agl or higher I have a hard time estimating this distance.

My concern is that I might pass up a perfectly acceptable site, just because it may appear too short. I've tried visually trying to figure this out but I find my brain just does not process this as easily as I would like.

Most of my flying is hilly, less-populated areas with few roads.

I'm hoping someone has some rule-of-thumb way of quickly estimating distance. Other tips?

30 years of flying has not helped at all with this particular challenge.

I just watched a video of a guy who crashed and killed his passenger. Afterwards he visited the site and realized there were much better landings options that he could have used, that in the air he thought were too short. This is what got me thinking seriously about this.
Click to expand...
One possible solution is to consider getting a plane with a BRS. Besides the Cirrus planes, C182 and C172 can have them added on.
 
Maybe a bit of an oversimplification, but I reckon if you're lookin' for a field, that means the engine(s) is/are caput you aren't likely to be passing up any....You'll look around and pick the one that looks to be the longest of the choices you've got there and now.
 
Tips on picking an off field landing site from a glider pilot...

Sadly, nothing on guessing the field length.

I am reasonably qualified to address this subject
having made, at this point in time, 169 off-airport landings
and have probably picked ten times that number of fields.
Consequently, most of the following material is based on
personal experience including that in the “Must never do”
category. Naturally, it is impossible for anyone to have
been exposed to all possible scenarios, even in a lifetime of
cross-country flying, so some of the material is derived
from other pilots encounters.
Click to expand...

 
Lndwarrior said:
I know I can land and stop my plane in 800 feet
Click to expand...

Fence posts are typically about 8’ apart, so just count the posts on a fenced field. 100 would be your minimum, but since the posts might only be 6’ apart and you want some margin anyway, you should probably count 150 posts to know the field is long enough.

Or you could just look for the longest flat area available and realize that’s the best you can do. Try to pick something that has a soft termination (fence, corn, even trees) rather than a building or a rock face.
 
455 Bravo Uniform said:
Look at the space between the threshold and the 1000 ft markers while overflying the airport at various altitudes and different distances/angles? Use your hand or fingers as a sighting tool for reference? Just some things to try. Let us know what you find out!
Click to expand...
Ok, that seems to make a lot of sense. I had wondered if something like that might work out. I will definitely try it.
 
Mikey52 said:
It's a shame you don't fly in the Midwest. A road every mile in almost perfect squares
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Yet another reason to leave California!

Except I happen to love it here. Living in the foothills hills of the Sierras is just too beautiful.

Plus, two years ago I flew my homebuilt to (almost) the east coast and back. I will admit flying over the mid west was far more relaxing because landing out options were almost a non-issue.

While the midwest states look beautiful from 3000 feet in the springtime, I think the flying would get boring pretty quick.
 
Half Fast said:
Or you could just look for the longest flat area available and realize that’s the best you can do. Try to pick something that has a soft termination (fence, corn, even trees) rather than a building or a rock face.
Click to expand...
This.

You’re probably not going to end up with a perfect plan. Accept the fact that you’re going to damage the airplane, but pick the place that will provide the best outcome for you and your passengers. You need to learn how to crash an airplane, and just hit the softest, cheapest thing you can find as slowly as possible.
 
Half Fast said:
Fence posts are typically about 8’ apart, so just count the posts on a fenced field. 100 would be your minimum, but since the posts might only be 6’ apart and you want some margin anyway, you should probably count 150 posts to know the field is long enough.
Click to expand...
If you're low enough to see and count individual fence posts, you're gonna be on the ground before you reach 150...
 
If you are not good at judging distances, learn how. Grab a can of marking paint and go mark off 1000' sections on a road or field. Fly over it at different altitudes and see what it looks like.

Three tips I heard from a smart pilot.
1. If you have an option, land close to a house or road - especially in a corn field. You may not be found until harvest if you go down in the middle.
2. A crappy landing spot is better than a great one just past where you can make it. No mater how bad you want it, you can not wish yourself past the laws of physics.
3. DO NOT STALL. Any crash landing anywhere is better than a stall - spin.
 
Lndwarrior said:
I've been flying for a long time and I practice emergency procedures quite a bit, but I totally suck at guessing off-field landing distances.

To be clear, your engine failed and you need to pick a suitable landing spot (assuming one is available).

I know I can land and stop my plane in 800 feet (assuming no vertical obstacle on approach) . So my first choice is to pick a field that's at least this long. Yet, when I'm up at 3,000 or 4000 agl or higher I have a hard time estimating this distance.

My concern is that I might pass up a perfectly acceptable site, just because it may appear too short. I've tried visually trying to figure this out but I find my brain just does not process this as easily as I would like.

Most of my flying is hilly, less-populated areas with few roads.

I'm hoping someone has some rule-of-thumb way of quickly estimating distance. Other tips?

30 years of flying has not helped at all with this particular challenge.

I just watched a video of a guy who crashed and killed his passenger. Afterwards he visited the site and realized there were much better landings options that he could have used, that in the air he thought were too short. This is what got me thinking seriously about this.
Click to expand...
It's pretty simple: your best option is probably right beneath you...concentrate on getting it there where everybody is going to walk away; the insurance company owns the airplane.
 
If you're in an emergency, pick the biggest field and plant it as close to the threshold as you can. Ground loop it at the end if you have to.

If you want to get fancy, precompute a distance/time rule for your airplane and use "fingers" to make a ruler for distance. Making the example math easy and assuming best glide is 60 kts + there are 6000 ft/nm, then I know I fly 1000 ft in 10 seconds / 500 ft in 5 seconds. So fly for 5 seconds and measure how many fingers distance that is from this altitude then use it as a guide to check a field. Parallax means it only works for nearby fields, but see the first sentence. You shouldn't really be hunting for a better field unless you've got a lot of altitude to work with.

Recompute d/t for best glide in your airplane. Don't make it complicated, the psychology says you'll lose 90% of your mental capacity in the stress. Say "I fly X seconds and that is y% of my desired field length". You don't even need to know the numbers, just know that you want a field at least a multiple of what you measure. My rule might be something like "5 seconds gets me 25% of my field, so I need 4x "fingers ruler" to be good".
 
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Lndwarrior said:
I know I can land and stop my plane in 800 feet (assuming no vertical obstacle on approach) . So my first choice is to pick a field that's at least this long.
Click to expand...

Prioritize clear and flat more than length. If you land on flat ground but run into some trees or a fence after 600' of ground roll, you'll still have slowed significantly and probably walk away, even if the plane is totaled. If you try for a longer field that has obstructions or is uneven, there's a chance you'll hit something and flip the plane while still fast, and injuries will be more likely.

When the engine quits, it isn't your plane anymore and your only objective is to escape safely from the insurance company's wrecked airplane.
 
Having actually done it, here's my advice. Make a plan early with the information you can gather very quickly and don't change from that plan unless you have a really good reason. Don't second guess yourself, but don't stop looking for a better solution either. Keep your priorities in place.

#1 priority - Keep flying the plane
#2 - work the problem
#3 - keep flying the plane
#4 - anything else
#5 - keep flying the plane

I was so low when the engine quit that my priorities were fairly simple after the first 20 seconds of working the problem.

1 - don't stall
2 - best glide until 50 feet
3 - get as slow as possible without violating #1
4 - don't hit something head on

I kept repeating to myself "don't stall" over and over.

I think it would actually be MORE difficult if you were higher and had more options as the original question suggests, but I think picking a good choice early and being open to change if you see something better is the way to go.

I thought about doing a few things different, like landing on a cross road, or pulling the gear back up, but they didn't seem "better" enough for me to change my plan, so I didn't. And in the end, it was the best choice.
 
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In an emergency you don't need as much space as you might think. For a quick estimate, assume 5 G is the max accel for a crash with high survivability, and you touch down at minimum controllable airspeed of 40 kts. At 5 G you come to a stop in only 14 feet / 0.42 seconds. A small spot can make a survivable landing.

Of course it's better to land somewhere big and smooth both for passenger safety and the airplane. But don't let that attitude trick you into forgoing a nearby survivable landing spot for one that looks better but is questionably within glide distance, or may have invisible hazards like wires crossing over a road. In an engine-out emergency, you can assume the insurance company just bought the airplane, your job is to ensure everyone walks away from it, and you don't need much space. Better to come wings level under control into a small bad looking spot, than lose control, stall, spin trying for a nice looking spot.

Lndwarrior said:
... I just watched a video of a guy who crashed and killed his passenger. Afterwards he visited the site and realized there were much better landings options that he could have used, that in the air he thought were too short. This is what got me thinking seriously about this.
Click to expand...
Exactly.
 
I, too, am pretty bad at guesstimating the length of a field.
I always carry my rotating plotter with my minimum required landing distance (plus some fudge factor) marked for 5,000, 4,000, 3,000, 2,000 and 1,000 feet of altitude.
It's certainly not perfect, but it has come in handy a couple of times.
I calibrated it by flying over the runway and making marks on the plotter.
 
Absent a reference unit of measure, if you get choices when it comes to your off field landing, count your blessings and go for the biggest and/or softest spot because once you commit, it’s likely you won’t get to change it.

It’s not like you’re loitering around at 5500 AGL when the motor packs it in; gravity and the insurance company own that plane going forward.
 
Shepherd said:
I, too, am pretty bad at guesstimating the length of a field.
I always carry my rotating plotter with my minimum required landing distance (plus some fudge factor) marked for 5,000, 4,000, 3,000, 2,000 and 1,000 feet of altitude.
It's certainly not perfect, but it has come in handy a couple of times.
I calibrated it by flying over the runway and making marks on the plotter.
Click to expand...
Finally! A specific answer to my question! Well, I think it's the second one. But thank you.

I keep a laminated checklist next to me at all times. This would be a perfect place to mark these distances.
 
Half Fast said:
Fence posts are typically about 8’ apart, so just count the posts on a fenced field. 100 would be your minimum, but since the posts might only be 6’ apart and you want some margin anyway, you should probably count 150 posts to know the field is long enough.

Or you could just look for the longest flat area available and realize that’s the best you can do. Try to pick something that has a soft termination (fence, corn, even trees) rather than a building or a rock face.
Click to expand...
In this area fence posts are normally a rod apart . A rod being 16.5 ‘
 
Lndwarrior said:
Finally! A specific answer to my question! Well, I think it's the second one. But thank you.

I keep a laminated checklist next to me at all times. This would be a perfect place to mark these distances.
Click to expand...
Unfortunately, it seems you missed the important message that others were trying to give you.
 
First rule, DON'T pick the marijuana or poppy field. Chances of survival drop significantly.
Second, if you have to pick one of those, stand close to the fire. It makes everyone more friendly.

Seriously though, my first thought was like yours, use the checklist to make marks, but also, your actual thumb for the rule. Maybe length instead of width.

Regarding woody areas and tree-top landings. From what I've seen in most videos, other than the stall/spin or high-speed planes, they seem fairly survivable. Don't want to ever know for sure though.
 
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I think at this point in my aviation journey I would be most concentrated on the best place I saw and best glide / wings level. I did go out the other day with my CFI and we picked a spot right next to us. I wanted to see how much altitude I would shed doing a simple 360 in the 172.... I was wondering ..... ok you have this suitable place but you are really high... too high to just slip, so what can we do to not overshoot or fly too far away. It gave me a good perspective on some different options to hit my mark. I don't think I would be comfortable doing a lot of measuring and debating up there, but I'm green. I might change my perspective as I get more experience.
 
Half Fast said:
When the engine quits, it isn't your plane anymore and your only objective is to escape safely from the insurance company's wrecked airplane.
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I almost got kicked out of the flight school I went to because I had this idea. The flight school wanted to hear that after an engine failure I would pick a field that will do the least amount of damage to the airplane. Their reasoning was doing so will keep the FAA off my tail. I stated that after an engine failure I do not care about the airplane or the FAA, I care more about getting my passengers and my butt safely on the ground and I will use the airplane in any way I can even if that includes tearing the airplane apart if that is what it takes to keep folks safe.

The powers that rule the flight school did not like that thought at all. Until the owners of the flight school decided airplanes are cheaper to replace than lawsuits.
 
Zeldman said:
... The flight school wanted to hear that after an engine failure I would pick a field that will do the least amount of damage to the airplane. Their reasoning was doing so will keep the FAA off my tail. I stated that after an engine failure I do not care about the airplane or the FAA, I care more about getting my passengers and my butt safely on the ground and I will use the airplane in any way I can even if that includes tearing the airplane apart if that is what it takes to keep folks safe.

The powers that rule the flight school did not like that thought at all. Until the owners of the flight school decided airplanes are cheaper to replace than lawsuits.
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The schools & instructors I've flown with over the years had the opposite attitude. People > airplanes. My responsibility as PIC is first to people on board, only after that the airplane. Most of the time there is no conflict, what's good for one is also good for the other. This may be what leads to confusion in emergencies when the two may conflict. Thinking of the airplane as an expendable means to save the people can clarify the priorities.
 
What @Salty said.

Speaking from very recent personal experience: things happen FAST. You are not going to have time to analyze. Nor are you going to be in a frame of mind to calculate anything. Your mind will be racing and you will fall back on simple, memorized procedures and principles.

The best you can do is make a quick decision, act decisively, and stick with your plan. I literally pointed at my selection and shouted "we're landing THERE!"

Pick the longest unobstructed flat area that you are certain you can reach. The more time you have to set up your approach, the better your landing will be. So my recommendation is if presented with multiple choices, pick the one you are already on a natural approach for that has no approach hazards such as wires.

BTW, monitor ground winds at nearby fields en route, and orient yourself for how that relates to your direction of flight. Again, you will not be in a frame of mind to process this in a real event, and you will have a lot of things racing through your mind.

Finally, forget about what you can do on a deliberate short field landing. You will not have power to adjust your approach to achieve an optimal arrival. You are likely to arrive with excess energy and dump as much of it as possible on short final. That is far preferable to arriving with too little energy and coming up short or stalling.

Did I say things happen FAST? Because they do. Any time you spend overthinking things is lost time and altitude that could have been spent positioning your aircraft for the best possible arrival.
 
Ed Haywood said:
Again, you will not be in a frame of mind to process this in a real event, and you will have a lot of things racing through your mind.
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Like, “oh, ****! This can’t be happening!”

The faster you can get past those, the better off you’re going to be, and the fastest way to get past them is simple procedures, not calculation or complex evaluations.
 
MauleSkinner said:
Like, “oh, ****! This can’t be happening!”
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That is EXACTLY what went through my mind.
Also, it may not be immediately clear that it IS happening. In my case the engine cycled through stopping, restarting, and surging for a good 60 seconds. During that time, I was thinking "this can't be happening. Ok, maybe it's not. Oh ****, it is. Wait, maybe it's not. Dang, it is."
MauleSkinner said:
The faster you can get past those, the better off you’re going to be, and the fastest way to get past them is simple procedures, not calculation or complex evaluations.
Click to expand...

Exactly. Everyone likes to think they will be Iceman. But the amount of adrenaline injected into your brain the first time is not to be underestimated. It is very much like being in a fight.
 
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