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tigisfat
March 28th, 2010, 16:18
Here's the situation. You're flying over the British Columbia in a Cessna 172. It's supposed to be a short flight with a friend for some supplies out of your cabin's small bush strip. Everything's going fine until the engine starts to run rough and cough. Your scan reveals nothing incorrect, and you haven't done anything wrong either. Regardless, now the engine is detonating LOUDLY. You instruct your friend to being looking for a place to put the aircraft down just in case while you continue to desperately fight the dying engine. Your wild attempts to keep it running fail in a crescendo of clanging that ends with a loud pop. Now you're looking at the prop (not moving) pointing straight up. The engine can't be restarted, either. You start trimming for best glide and look at your friend, who shrugs at you and tells you there flat out isn't anywhere to land. There's an endless sea of rocky peaks and steep slopes covered with trees. A valley comes into view and it's apparent you'll have to land in it or face the rocky cliffs. There's a flat area and a small lake of unknown depth. It becomes rapidly apparent you have to make your decision soon. There are only two options. You can land in the 50 foot tall trees or land in the water.

Which do you choose and why?

djscoo
March 28th, 2010, 16:26
I'd choose the water. I could imagine the fixed gear would cause the aircraft to cartwheel once it hits the water. If it was retractable gear, water would be a no-brainer.

PRB
March 28th, 2010, 16:40
How big is "the flat area", presumably next to the lake? Maybe I'd attempt a landing there. Short that, water. Because it's softer than wood and rocks... This seems too easy though. Something tells me you're going to tell us we were supposed to pick granite and oak over water, but I can't imagine why, given the details supplied in the scenario.

viking3
March 28th, 2010, 16:48
Trees will absorb most of the impact energy so I'll go with them. I've done a few spectacular bellyflops so I know how hard the water can be.

Regards, Rob:ernae:

HouseHobbit
March 28th, 2010, 17:02
GO for the trees, if you are lucky you can pick off a few squirrels while crashing..
And have them for dinner while you wait for Help.
allways thinking of food here.. LOL..LOL..

Willy
March 28th, 2010, 17:05
I'd be asking my friend if he could swim as he's fixing to get wet

T Square
March 28th, 2010, 17:07
This reminds me of an old Truckdrive joke I heard many years ago.

"During a test at a truck driver school this question was asked. "You and your partner who is asleep are at the top of a steap valley at the bottom of the valley there is a one lane bridge over a deep gorge. Seeing that a truck is coming down the other side of the gorge, you apply your brakes to find you have no brakes. You signal the truck on the other side of the gorge "no brakes can't stop". The truck on the other side of the gorge signals back "no brakes can't stop". The question is what do you do next ? One student says I would wake my partner up ! The instructor Asks why ? Student answers "I bet my partner ain't never seen a wreck like the one we're about to have and I know he probably wouldn't want to miss the chance to see it." :ernae:

Railrunner130
March 28th, 2010, 17:11
The water is your best bet. By the sounds of it, there may be a suitable landing area off to the side, which would easily be the best of the three options. Trees serve as an impaling hazard. Not to mention, it's easier to get out of an aircraft in water than 100 feet up in trees.

To slightly lessen your chances of a bad landing, crank the starter so that the prop is horizontal, not vertical. For a water landing, pop the doors slightly open and try to stuff something in the door crack, so that a jarring of the airframe does not seal the doors shut.

jmig
March 28th, 2010, 17:13
The tops of fir trees bend. That water is damn cold.

If you do try the water, be sure and open the doors before impact.

N2056
March 28th, 2010, 17:18
I say you go into the water. As was pointed out earlier key the starter to get the prop horizontal and prop open the door a bit. I would try to make the approach such that I would hopefully end up near the shore!

gigabyte
March 28th, 2010, 17:23
Well if you want to know what "Can" happen for that choice in real life - if you have the right aim and put a 172 in between 2 trees, the wings come off rather cleanly, and you can walk away - the 172 doesn't do so well, but the crash is survivable. True Story! 1996 or 97, my cousin was riding right seat for a student trying to get in his hours for his license (I do not know all the details Brian is not an instructor he was just helping the guy out as he was not yet allowed to solo), they flew from Sherwater in Dartmouth, NS to Yarmouth, did a touch & go and on the return ran low on fuel, actually ran OUT of fuel. The pilot kind of lost it, and Brian kept his head, they ended up doing a belly flop in a ladies back yard after cleaning the wings off the "Rental" 172 coming in between two large birch trees. The choice was St. Margaret's Bay, a selection of small back yards along the shore, or the two trees, Brian said afterward he didn't think the water was a good idea, because the landing gear would have caused the plane to flip, the yards were small and none large enough to land & stop, so he went for the trees. The NTSB inspector told him later he made the best choice, and he and the pilot walked away so there was little doubt.

I have been up with him several times since, the only times I have flown in small planes, the wife said I was crazy, I always say the same thing, I would prefer to fly with him he knows how to crash the safe way :)

tigisfat
March 28th, 2010, 18:48
How big is "the flat area", presumably next to the lake? Maybe I'd attempt a landing there. Short that, water. Because it's softer than wood and rocks... This seems too easy though. Something tells me you're going to tell us we were supposed to pick granite and oak over water, but I can't imagine why, given the details supplied in the scenario.


Nope, I am a pilot but I don't presume to have a 'correct' answer in light of the varying opinions of the masses and the other pilots here with more experience than I. There may not be a correct answer to this. I definitely wouldn't try to set it down on the mountain tops.

You asked about the flat area: it's presumed to be wooded and with only a lake.


What I would do? I'd come in over the lake pointed at the woods and land it to a full stall (and then some) and go skipping/sliding up onto the shore and into the trees. I'd try to point it between two trees to dissipate energy better.

Ken Stallings
March 28th, 2010, 19:02
Well, clearly, it would be very poor pilot planning to get yourself into such a situation. There are few areas embedded with dense forests to the extent you have no other viable options if you simply give yourself enough altitude and/or modify your VFR routing slightly.

However, I will choose the water, and I will try to land parallel to a bank vice the middle of the water on a river or lake. That doesn't mean that landing in trees is an automatic death sentence, but it is leaving a lot outside your ability to control as a pilot.

Water ditchings, even in a fixed gear high wing aircraft like a Skyhawk, isn't horrible. The plane will nose down and the stop will be sudden and shocking. So, make damn sure your lap and shoulder harnesses are cinched tightly and I mean digging in tight.

Then, whether it is the trees or the water, unlock and open both doors. Yes, the water will likely slam the door shut, but with the latch unlocked you can likely push the door open even if it binds. Also, open up you window so that as the aircraft settles into the water, you can let the pressure equalize as the water comes in and push open the door. Once you have stopped unfasten your harness immediately and push open the door quick as possoble.

With luck, you can get the door open quickly. If not, then relax and allow the water level to equalize and remember that the high wing will prevent the aircraft from sinking for at least a half hour or so, so you won't drown if you keep your wits about you. If it is nightime, the turn on your landing lights. The key is to stall as you hit the water and use the rudder to keep the nose pointed straight ahead long as possible, Also, make sure both main gear touch the water at the same time and always anticipate you will skip off the water on the first touchdown. It's always the hit before the stop that's the most severe.

Landing in trees of a dense forest requires that you essentially treat the tops of the trees like a runway surface and you attempt to touch down on the tip spine of a tree at stall speed. The goal is to literally stick the plane on top of the trees. If you are dealing with spindly trees, the plane will collapse on top of the trees and you will break branches as you come down. What you don't want to do under any circumstances is come down between trees and smack one in the trunk right in front of you.

There have been cases of survival without severe injuries doing this on a tree, but it is the most risky type of crash landing.

Under either situation, abandon all hope of the aircraft surviving. You are flying an insurance write off.

Cheers,

Ken

Ken Stallings
March 28th, 2010, 19:13
BTW: Allow me to expand some on my first point. I have flown over about every part of the United States and at least in the US, there is no where that there isn't a dirt road, paved road, logging trail, or flat field in glide distance if you are constantly evaluating and adjusting your routing and altitude and asking yourself, where would I put this thing if the engine suddenly quit.

Having your site selected in your mind is half the battle.

Cheers,

Ken

Piglet
March 28th, 2010, 20:46
Turn off Crash Detection...
Problem solved...

harleyman
March 29th, 2010, 03:18
Turn off Crash Detection...
Problem solved...



Perfect answer ...............

PRB
March 29th, 2010, 04:30
Turn off Crash Detection...
Problem solved...

Hehe. And turn down the autogen so there won't be any trees!

Ok, seriously. If the plane is a fixed wheel tail dragger, I would think this would affect the desicion, as it would be likely to flip over on a water landing. A logging road would probably be bad, even if you could see it from above. It would probably be steep and have sudden turns. I sort of like the "land on the beach in a stall and hope to be going slow by the time we reach the trees" method.

kilo delta
March 29th, 2010, 06:08
I can't swim.....so it'll be the trees for me!

Snuffy
March 29th, 2010, 07:40
If I have the glide time, I might go for the coming in low over the lake and head for the nearest shore and hope I can belly in on the beach/shore and grind to a stop before hitting the trees.

gigabyte
March 29th, 2010, 13:20
I probably have not been so "one way vs the other" in my post, every situation will be different, and there was no mention of wind condition or direction in the initial question, which I think would factor in some cases. In my example of the actual crash landing that my cousin did, the crash investigator told him without a doubt he had done the right thing, apparently the water conditions (an Atlantic Ocean Bay) at night with no way to judge the depth or accurately determine if there were rock at the surface and, the hilly conditions in the available area made his choice the best one. I do recall him mentioning his timing was perfect as he was able to stall the aircraft at just the right moment to minimize the violence of the impact with the trees.

Ken Stallings
March 29th, 2010, 15:50
Landing on the ocean would be considerably different than the average mountain or forest area lake or river. No question about that.

Of course, with the ocean, you should absolutely chose to land on the beach if available. If it's a rocky crag dropping directly into the ocean, yep, you don't want to ditch there. Even if you get out of the aircraft, you're likely going to get slammed into the rocks and get killed that way.

Still, I come back to the notion that I have never been forced to fly over an area where glide distance put me over such a dire situation of trees, lake, river.

Ken

OBIO
March 29th, 2010, 16:40
Being a bit more of a problem solver, here is how I would handle that situation. I would have the person in the right hand seat take over the plane, then I would tell him/her that I was going to go scout out a good landing/crashing area....open the door and jump. A few seconds later, I would pull the rip cord and deploy my parachute. HA HA. See I knew that earning my Chicken badge in the Boy Scouts would come in handy!

OBIO

Major_Spittle
March 29th, 2010, 16:57
I'd pick the water everytime. Better to hit the water at 60knots and flip/stop than to hit 50ft tree tops at 60knots, flip flop spin smash and then drop engine first 50ft putting the firewall through your face.

tigisfat
March 29th, 2010, 17:17
I'd pick the water everytime. Better to hit the water at 60knots and flip/stop than to hit 50ft tree tops at 60knots, flip flop spin smash and then drop engine first 50ft putting the firewall through your face.

until everything you have is wet, you're facing down hypothermia and night is approaching.

viking3
March 29th, 2010, 17:50
We get at least 1 or 2 crashes a winter in northern Manitoba, it seems, where the planes hit the spruce. Usually almost every one gets out. I think the deal here is that our Black Spruce trees are pretty spindly and scraggly and only get thinner the farther north one goes, so they make for a pretty soft landing. Not sure I tackle any 200 ft tall Sitka Spruce on the west coast. The only good thing is after the crash you have lots of firewood.

Regards, Rob:ernae:

Dain Arns
March 29th, 2010, 18:14
Easy. Deploy the BRS. :d

http://www.brsparachutes.com/

Ken Stallings
March 29th, 2010, 18:20
I'm not sold on those chutes. I can see where if you had lethal structural damage preventing aircraft control, then they are your best bet. However, in any other circumstance, I still believe you are best to fly the dang airplane! Once you pull the ripchord, you have surrendered control to the winds.

And it works provided you land on reasonably level terrain.

But what if instead you land on a hill, or mountain, or even on top of a tall tree and your cockpit gets impaled, or the plane has the chute ripped off by a tree and your aircraft tumbles the final 25-50 feet?

I recall reading where at least one, and perhaps two, pilots were killed after deploying that chute because he landed on rough terrain and the airplane went tumbling down.

What I really hate is Cirrus making an overt marketing effort to say this is an approved solution for dealing with spatial disorientation in instrument conditions for VFR pilots caught in weather. First, that has already been shown to encourage VFR only pilots taking off in marginal weather because they "can always pull the chute!" Second, the best way to avoid spatial disorientation is to get more training and earn your instrument rating! In terms of flying into rough IFR weather even with an instrument ticket, you pull that ripchord in vicinity of a thunderstorm or icing, and you've likely signed your death certificate because when the convective finishes business with your chute, or the icing collapses the chute, you're going to have a long ride to ponder your decisions! Hopefully, by that point, you'll be knocked unconscious and out of your misery.

Ken

tigisfat
March 29th, 2010, 18:22
Easy. Deploy the BRS. :d

http://www.brsparachutes.com/

For a dead engine? The BRS has a descent speed not unlike landing speed.



Okay then, let me ask you this. Do you deploy the BRS over the trees or the water? touche sir. :icon_lol:

Ken Stallings
March 29th, 2010, 18:26
We get at least 1 or 2 crashes a winter in northern Manitoba, it seems, where the planes hit the spruce. Usually almost every one gets out. I think the deal here is that our Black Spruce trees are pretty spindly and scraggly and only get thinner the farther north one goes, so they make for a pretty soft landing. Not sure I tackle any 200 ft tall Sitka Spruce on the west coast. The only good thing is after the crash you have lots of firewood.

Regards, Rob:ernae:

An outstanding observation!

BTW: Since you're up there in a region I haven't flown in before, do you think it's fairly easy for a VFR pilot to simply make small modifications to his routing and/or altitude and keep himself in position for an engine out glide landing on a reasonable dirt or paved road or empty and reasonably level field?

Ken

hammer353
March 29th, 2010, 18:31
As pilot, i would prefer landing on the tops of the trees then in the water. Landing in the water is like hitting a cement wall.

Ken Stallings
March 29th, 2010, 18:39
As pilot, i would prefer landing on the tops of the trees then in the water. Landing in the water is like hitting a cement wall.

True depending upon your impact angle and speed. Water is not compressible, which is why boats can float. Water simply displaces.

However, if you skim the water at a slow speed, then it doesn't need to be like concrete. The volume of water isn't that large and it can displace since its on the surface and has someplace to displace easily to.

Yes, if you crash into it -- like those many scenes from World War II -- then it is like concrete because you aren't skimming the surface, you are trying to compress the water because it doesn't have the time to fully displace. So, it ends up displacing your aircraft!

From the Sully ditching to many examples of ditchings in World War II, it can be done. An AC-130 and C-130 from Equador (I believe) successfully ditched and most onboard survived.

Cheers,

Ken

Dain Arns
March 29th, 2010, 18:53
For a dead engine? The BRS has a descent speed not unlike landing speed.
Okay then, let me ask you this. Do you deploy the BRS over the trees or the water? touche sir. :icon_lol:

Trees.

If, IF I knew that I could not make a safe dead stick landing, Ken, I see the BRS as a more viable solution in this particular situation.
I'd rather float into trees, than try to land on top of them.
Plus I'd hope that parachute would stay up on top of the trees. Give searchers something to see by air.


As pilot, i would prefer landing on the tops of the trees then in the water. Landing in the water is like hitting a cement wall.

I had a lengthy reply about this, then deleted it and went with the BRS response instead.
Okay, the BRS is kinda a smart ass response. I do that, God created me this way. :icon_lol:

Water with fixed gear means like hammer353 said.
I've always heard of it as landing in wet concrete.

Three words:
Sudden Deceleration Trauma.

I don't care how tight your straps are, you going to have secondary sudden deceleration to ALL of your internal organs, including your brain, as they continue forward after the impact and sudden deceleration.
The brain slamming into the inside of the skull, for example.
I know a few things about this, seen it for years when I was working on the road. Same thing happens in car accidents.

Combined with possible chances of drowning, but the big factor is hypothermia.
Water landing means getting wet. Wet in higher altitudes and the mountains .
It gets cold when the sun drops down in the mountains.
Being wet on top of it, with a possibility of even minor, yet survivable hemorrhaging from sudden deceleration trauma, means your chances of survival to the next morning are being greatly reduced.
Well, that's my thoughts anyway...

So yup. I'd try to pancake into the tops of the trees.
Probably survive the drop to the ground better via branches.
I mean, guys had parachute failures during WWII, and survived falling into trees.

But that just my opinion. Everyone's is unique. :icon_lol:

Dain Arns
March 29th, 2010, 19:09
BTW, I don't think anyone's answer is wrong here. All good answers. :applause:
As PIC, you gotta make the choice at the moment.
If I knew the area has 200'+ tall trees as viking3 said earlier, I'd probably switch to water too. :icon_lol:

tigisfat
March 29th, 2010, 19:09
My scenario was for a Cessna 172 to eliminate variables and ask the decision. What if you can't retract the gear or pull the BRS cord?

I'm pretty sure I'd have to make up my mind at the moment based on what the trees and water looked like.

N2056
March 29th, 2010, 19:20
I have to agree...unless you have an actual snapshot of the situation it is hard to make a call. My flight 'training' to date has been through flying with my Dad, and one of the things he asks me a lot is where would I put down if I lost the engine now? I tend to spend a lot of time either looking for other traffic or pondering where that possible landing area is.

tigisfat
March 29th, 2010, 19:34
I don't think one is worse than the other, to be honest.

viking3
March 29th, 2010, 19:47
BTW: Since you're up there in a region I haven't flown in before, do you think it's fairly easy for a VFR pilot to simply make small modifications to his routing and/or altitude and keep himself in position for an engine out glide landing on a reasonable dirt or paved road or empty and reasonably level field?

Ken

It's pretty much floats or skis to make a safe emergency landing once you get north of here. In fact if you draw line NNE of Gimli all the way to Hudson's Bay you only cross one dirt road and would not cross an airstrip. That's somewhere around 500 miles. The terrain is exposed rock, swamp and thick stands of Black Spruce with thousands of lakes and rivers cutting through it. The East side of Lake Winnipeg is under consideration for a UNESCO World Heritage Site as one of the largest undisturbed tracts of land left on the planet.

Ken Stallings
March 29th, 2010, 19:57
Let's see what some raw statistical analysis of Cessna Skyhawk (and other fixed gear high wing GA aircraft) can tell us:

http://www.equipped.com/ditchingmyths.htm

Looking at the raw numbers, it turns out there is no significant deviation between low wing, high wing, retract or fixed gear in terms of exgress probability from ditching. Clearly, if you ditch near the bank, you have less distance to swim, which obviously increases your survival odds. Hypothermia can certainly be a factor, but no different than getting wet from a rain storm.

Most significant of all, it seems there is around a 90% odds of survival from a ditching, especially if you do it right (touchdown at stall, not into swells, and keeping the nose pointed up with full aft elevator and rudder keeping the nose centered.

Cheers,

Ken

Ken Stallings
March 29th, 2010, 20:00
It's pretty much floats or skis to make a safe emergency landing once you get north of here. In fact if you draw line NNE of Gimli all the way to Hudson's Bay you only cross one dirt road and would not cross an airstrip. That's somewhere around 500 miles. The terrain is exposed rock, swamp and thick stands of Black Spruce with thousands of lakes and rivers cutting through it. The East side of Lake Winnipeg is under consideration for a UNESCO World Heritage Site as one of the largest undisturbed tracts of land left on the planet.

Sounds like a dynamite argument for a twin engine aircraft or a single with floats! :engel016:

Ken

norab
March 29th, 2010, 20:12
don't know how relevent it is to this situation since the 172 wasn't biult by the "iron works" but I know that F4F wildcat pilots were advised to aim between tree trunks in a crash landing so as to snap off the wings and dissapate as much energy and velocity as possible before coming to a stop giving the airframe structure the best chance to protect them

tigisfat
March 29th, 2010, 20:14
Sounds like a dynamite argument for a twin engine aircraft or a single with floats! :engel016:

Ken


To hell with that, it sounds like a dynamite argument to cruise at mach 3.2 at 80 thousand feet with the heater keeping you warm.

EasyEd
March 29th, 2010, 20:40
Hey All,

Are the trees hardwoods or softwoods?

Is it hard water or soft water?

Enquiring minds need to know! :d

-Ed-

boxcar
March 30th, 2010, 11:45
.
... Trees... you can climb down from them. Handy if one cannot swim.

http://i425.photobucket.com/albums/pp337/ViewX2/Peerhovenstrikesagain.jpg
.
.

Odie
March 30th, 2010, 13:15
Well, I'd go into the trees....if it's stuck in the treetops, it may be easier to for a SAR effort to spot. On the other hand, I'd probably slip trying to climb down the tree, fall, land on Bigfoot. Now he's upset with me so he drags me back to the cave, puts an apron on me and I'm doing his dishes for the next month or so !!! And I'd hate that because dishwater really wrinkles up my hands.....:icon_lol: