Emergency Landings (Split from PushRod Lifter Broken)

How to keep the Cessna 170 flying and airworthy.

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N2865C
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Post by N2865C »

Here is a link to an interesting article analyzing NTSB reports of ditching. They came to about the same conclusions as Aviation Safety.

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

I think given a choice between going into the trees, hitting a hard object or ditching, I would choose the water. Of course every situation is different. I hope I never have to make that decision.
John
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Post by N2865C »

N2865C wrote:Here is a link to an interesting article analyzing NTSB reports of ditching. They came to about the same conclusions as Aviation Safety .


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

After reading the article again I realized it is the same article that was in Aviation Safety.
jc
John
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mvivion
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Post by mvivion »

In full agreement with George's mental checklist, I respectfully offer the following, to take the place of "fly the airplane":

"Pitch to a safe attitude"

Why? If you are at 5000 agl, there is no need to immediately achieve best glide speed. You are already pretty close to a "safe attitude" in that circumstance, and can mosey your way toward best glide speed as time and other duties permit.

On the other hand, if you are at 20 feet, just after lifting off, and the engine fails catastophically, you may have to push pretty aggressively on the yoke to keep the airplane from stalling. In this unique circumstance, this comprises the entire engine failure checklist, cause you won't have time for anything else, and this is the one thing that can save your life.

Then, George's mental checklist starts, if you have time:

Carb heat, for all the reasons he noted,

Fuel: Switch tanks

And so forth.

Pitch to a safe attitude takes care of the "fly the airplane" deal, and works wherever you are.

If you ever have an engine failure at low altitude just after takeoff, it could save your life, and at that point, that is job one.

I agree fully, though, that you need to commit the simple steps that George presented to memory. Then if time permits, go to a written checklist to verify that you didn't miss anything.

Believe me, it's easy to miss things when the prop stops.

Mike Vivion
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lowNslow
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Post by lowNslow »

Mike, 5000' may not be much altitude when the landing spots are few and far between. The best glide is going to be achieved at the best glide speed, so better to trim it to the correct speed (vs. pitch) AND get the airplane going in the general direction of a landing site. I think George's concern about carb ice is not a real concern because an enginge gives pretty good warning when it starts icing up. The engine will begin to run rough and loose RPM and is not liking to just quit.

If the airplane is at 20' the last thing you want to do is do a checklist, just "fly the airplane" and don't stall as you put it in the best spot available.
Karl
'53 170B N3158B SN:25400
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mvivion
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Post by mvivion »

Karl,

I agree that GENERALLY carb ice gives you warning, but not always. Also, remember, you can MAKE carb ice AFTER an engine failure from fuel exhaustion for example, so getting the carb heat on quickly recovers the residual heat in the muffler asap, and takes a nano second.

My argument for pitch being primary is that, if you have an engine failure very close to the ground on takeoff, it isn't a simple matter of picking the best place to park it: That is already decided. But, pitch is critical. If you don't shove that yoke forward, the airplane will most likely stall, and that's not a good thing. The 170 has light elevator forces, but that's not true of all aircraft, either. In any case, with a low level engine failure, after takeoff, the airplane will never get up to best glide speed, but pitch is critical for survival.

Are you advocating to immediately slow the airplane to best glide speed, when at cruise altitudes?

My point was simply that if you are well above the ground, there is no immediate need to get to best glide speed, so I let the airplane gradually decelerate to best glide, WHILE I'm taking care of other checklist items. In this case, my pitch admonition is already taken care of: hold what you got, and the airplane will decelerate to best glide.

No matter where an engine failure occurs, the pitch attitude of the airplane should be job one. Pitch to a safe attitude will save your life at low level.

If you've never experienced an engine cut at low level on takeoff, it is a very abrupt experience, and pitch is the only thing that will save you. We used to have a certifiably crazy check airman who would routinely give you an engine failure right after takeoff at some point in nearly every checkride. I always thought he was nuts, but it is an interesting experience. Once.

I don't advocate training like this, and frankly the liklihood of an engine failure immediately after takeoff is really low.

But pitching to a safe attitude is always a good idea.

Don't forget that an airplane can stall at any speed. Angle of attack is what really matters.

Best glide just extends the distance you can glide. In fact, there are situations when you DON'T want to use best glide speed, for example, right over an airport.

Also, try taking your best glide speed right into a flare when the airplane is empty, with just you in it and a bit of fuel, as in forward CG. From best glide speed, you'd best be spot on precise with where you initiate a flare, cause you won't have much energy to expend.

Best glide is a tool, not a mantra, and getting the airplane to best glide speed after an engine failure is well down on my list of priorities.

Just some thoughts from one who's been there,

Mike
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Post by AR Dave »

I agree, maybe! When you lose an engine just after take off at 200 ft., you can throw all the Vx, Qr, Psq, out the window. And there ain't no flaring when you finally get there! Just delicately try not to stall while you wobble around to line up with the target. Then remember "just fly the plane" with very non effective elevators!
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3958v
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Post by 3958v »

It is probably a real good idea before every take off to think of what you are going to do in case of a power failure. We lost a pilot at our home airport a few months ago when she lost her engine at about 200 ft on take off in her Cherokee. A friend of mine who witnessed the accident said she never pushed the nose over. It is something you almost have to do instinctively because there will be little time for indecision. Bill
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spiro
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Post by spiro »

Roesbery wrote:...at 50 mph, if you can spread a stop evenly over 9 feet you should survive without serious injury.
that's an even deacceleration of 9.3 G's, for 1/4 sec.
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thammer
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Post by thammer »

spiro wrote:
Roesbery wrote:...at 50 mph, if you can spread a stop evenly over 9 feet you should survive without serious injury.
that's an even deacceleration of 9.3 G's, for 1/4 sec.
The discovery channel had a show that included a segment on G-forces and testing that had been done. There was this one guy who jumped off a high platform and landed flat on his back. They varied the height of the platform and the thickness/density of the mat he landed on to control the rate and distance that deceleration occured over. They found that the human body easily withstood 100g's without injury when the deceleration was not instantaneous. I forget exactly how small the distance was but it was in the neighborhood of a few inches, 6 or 8. Pretty interesting not to mention the cajones required to be that test victim....I mean pilot.

In airplanes we have sharp edges to worry about. Shoulder harnesses are a must if you want to keep your teeth.

tye
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Post by GAHorn »

lowNslow wrote: I think George's concern about carb ice is not a real concern because an enginge gives pretty good warning when it starts icing up. The engine will begin to run rough and loose RPM and is not liking to just quit.

.
I guess that's why so few engine failures are attributed to carb ice. :wink:
Don't forget that carb heat also provides an alternate induction-air source.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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lowNslow
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Post by lowNslow »

.[/quote]

I guess that's why so few engine failures are attributed to carb ice. :wink:
Don't forget that carb heat also provides an alternate induction-air source.[/quote]

Not saying it will not cause an engine failure, just saying it gives lots of warning. See lots of carb ice here on the west coast due the cool moist air coming off the pacific and have never heard of an engine just quiting without warning. Plenty of time to get to the carb heat if your paying attention. :wink:
Karl
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GAHorn
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Post by GAHorn »

Apoligizing if I seem to be "harping" on this issue but.....
My attempt at sarcasm was deliberate (and playful). While it's true that carb ice gives plenty of warning...to a modestly attentive pilot..
The fact remains that sudden engine failure is actually not uncommon due to carb ice. "Sudden"....meaning "big surprise".... because pilots who've never experienced it become complacent and then as the RPM is seen to be a "bit low" simply add throttle. A while later they do it again. A while after that they don't seem to notice that they've run out of throttle....assigning it to their cruising altitude as normal.
Next thing he knows.....the engine quits running smoothly....and in fact may completely die. It is a "big surprise" that he's suffered a "sudden"engine failure. 8O
That "lots of warning" goes unnoticed many times each year by those who should have known better.
Hence my attempt to remind everyone that each year there are experienced pilots who "suddenly" had an engine die...and who loudly declare there's no reason for it....except the accident investigation concludes it was carb ice.
Don't think it cannot happen to you! (Hence my own recommendation to others to pull carb heat as an immediate memorized action. Only a few seconds of a windmilling propeller will clear the carb heat system of any residual heat which may have gotten it restarted for you.) IHMO
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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Post by AR Dave »

Actually the first time, I thought I must've changed RPM's or something so I adjusted the mixture. Think I pushed it in towards rich just a bit, then a bit again, and maybe again. Next, that was the WRONG way to go, so I tried leaning more aggressive testing, HEY I'm trapped! Spotted the landing strip, Traci asked why do you always get me in these situations, and just then it dawned on me :idea: - Carb Ice. When I pulled the Carb Heat, I think a glacier went through! But it was smooth within a minute. No problem recognizing it since that first lesson! :wink:
zero.one.victor
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Post by zero.one.victor »

I've made it a habit to pull on the carb heat for 15 or 20 seconds every once in a while. Occasionally the rpm will come back up a little higher than it was, leading me to believe that I had been suffering from a little carb ice. I can believe George's description of carb ice creeping up on a person, leading to the engine crapping out "suddenly".

Eric
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