Loss of power on takeoff causes?

[painless]

Out of respect for those lost near Norman, OK, I am posting this question in a separate thread.............

I would like to get some input as to common causes of losing power on take-off. My thoughts are as follows:

1) Carbice
2) Contaminated fuel
3) Induction system blockage (eg snow in the intake)
4) Drawing fuel from a depleted fuel tank
5) Steep climb angle and not having auxillary fuel pump on (read that no or very low fuel pressure)

6) Blocked fuel vents
7) Loose/leaking fuel system fittings


Any other possibilities?

Please do not construe this as an attempt to analyze any accident in particular.


Regards,

[Mel]

Jeff,
I will agree with most of your "causes" except for #1. You are not likely to experience carb ice on take off. Mainly because carb ice normally does not form at wide open throttle. I ususlly forms on the throttle plate when it is at an angle ot the incoming air. Not saying that it can't happen, just that it NORNALLY doesn't.

[grahamcalder]

Many years ago I was introduced to the pleasures of flight at Shoreham in the UK by an anaesthetist friend based in Victoria BC who was accustomed to Cessna 150's where the custom was to leave the fuel valve open.

After initiating me in a 150 he grabbed the opportunity of flying the club's Tiger Moth, wonderful stuff!

Next was to try one of the club's Condors. Fuel valve habitually turned off after flight, but as he found out there was enough fuel in the system to startup, taxi, do the run up and take off. 50' up the engine quit!! The FI landed it ahead and there were red faces throughout!!

Yet one more for your list,

Graham (UK "painless" !!!)

[Harold Lanfear]

I've only had two ; one on takeoff at 400 AGL, where I broke a bolt in an intake valve pushrod. It backfired once, then croaked. Fortunately, I was in my Kitfox and easily made it back safely. Practice helps - the only problem I had was the voice in my head telling me "you never turn back to the airport", but after turning to the nearest field, I could see the airport was no problem.

The second was at night in a helicopter and also a valve - the valve seat separated from the stem, broke up and then the pieces destroyed the turbocharger. Had about 40% power, but enough to land in a field with no problems. The engine croaked when I rolled the power back.

The reason I'm responding is twofold - Practice engine out procedures often and be prepared for anything. Keep a landing spot in mind always.

By the way, if you go to the AOPA.org site and find the 2004 Nall Report (search for Nall, it will come up); there are a lot of interesting statistics and you will find that anything can break; some things you can control, but you still need to be ready. BTW, carb ice is normally a descent, sometimes cruise problem as it takes a while to build up.

PS - Jeff, I was born in Marinette and lived in Amberg - bet your weather is worse than ours in PA now.

[rv6ejguy]

While fuel related issues are the prime culprit in power loss incidents, I am surprised at the number of valve and con rod failures, even on some low time engines. Doesn't matter what is stamped on the valve covers- anything can break.

Have a good plan before takeoff and know what you will do if you lose power before you throttle up. There is little time to think, you need to respond automatically and quickly.

Not a bad idea to contemplate what will happen to you and your airplane if the engine fails right over those trees at the end of the runway.

Many of these RV accidents which have looked survivable from the outside are indeed fatal. High descent rates at airspeeds just above the stall can exceed 1500 fpm (25 fps) with no energy left to flare. Spinal injury is almost certain as a minimum. Landing gear intrusion into the cockpit on A models is also very likely due to the shearing of the retention bolts. Ask me how I know.

Never be tempted to stretch the glide. Maintain 85 knots down to an early flare and probably use no or half flap as elevator authority with full flap and zero power is severely reduced.

[painless]

Mel:

I included carbice due to a local pilot encountering it on takeoff with a C150. He was able to land on M35 highway without damage. I agree that it is very uncommon to have ice on takeoff, but then again with the above example, we are talking about a Continental, which as I understand it are a bit more prone to carb ice.

Harold:

Yup--- winter has arrived. Lows in the teens. This after we hit 50F last week. As we say here in Wisconsin, if you don't like the weather, just wait a couple minutes...It'll change!

Regards,

[Brantel]

I had a 152 swallow the inlet screen on the front of the cowl at about 400ft on takeoff at night. RPM dropped to about 1100. Pucker factor was real high because there is no options to land close in and straight out on 23 at MOR once you pass the perpendicular highway on the end.

Luckily the 1100 rpm gave me just enough power to complete the 180.

[gmcjetpilot]

Originally Posted by painless

common causes of losing power on take-off. My thoughts are as follows:

1) Carbice
2) Contaminated fuel
3) Induction system blockage (eg snow in the intake)
4) Drawing fuel from a depleted fuel tank
5) Steep climb angle and not having auxiliary fuel pump on (read that no or very low fuel pressure)
6) Blocked fuel vents
7) Loose/leaking fuel system fittings
Any other possibilities?

Accidents happen and it makes you think.

Fortunitly loss of power on take off is rare. Often engine failures are preceded by signs that go unnoticed or ignored. One guy rebuilt his fuel tank and got the line blocked with junk. Any thing can happen. With that in mind, PLAN for it.

The OK accident looks like a stall? The airframe is all there in one spot, but I don't know. Vertical impact can cause massive spinal and internal injuries. You have to be ready to take your lumps, but take them under your terms not gravity's and stall-spin terms.

We really are not prepared to intentionally crash our planes, but that is what you must do if the engine quits sometimes. The idea is make it hurt the least and walk away. That means flying into the ground. We just are not use not seeing a runway. My primary CFI made me commit my forced landings fairly low. Its amazing what you see down low. Not so sure decades later if that was a safe thing to do, but it taught me a lot. I think pwr off landings to a runway is great practice and safer.

In the airlines we say OUT LOUD a detailed plan for what we'll do in the event of an engine failure to the whole crew, every flight. We'll even rehearse or repeat the engine out procedures, speeds, especially on the first flight of day. Of course with 2 plus engines you have options, but the principle applies to single engine. I do this when flying my RV single pilot, at least in my head. What am I going to do, but I'll say it out loud sometimes. The choice is easy if the engine quits in a single engine plane, land or stop.

When will you abort the takeoff or go back and land on runway?
What will you do if you can't stay on or land on takeoff runway?
Where will you land, straight, slight turn left or right?
Forced landing procedures:
speed, flaps, elect, fuel, belt, trim, radio call?
Engine trouble shoot procedures:
boost, c-heat, tank, mixture, ign, min altitude to attempt re-start
Min safe altitude is safe for a 225 + 45 degree turn back or if safe at all?
(winds, runway length, obstacles may make a turn back very dangerous or impossible)

If you fly the plane and land under control at min flying speed, injury to crew can be minimal. You have to believe that and practice it. Power off (idle) spot landing practice can help.



With full power RV takeoff the noise is way up, but if the engine fails you have to be ready to dump the noise down almost as much below the horizon as it was above in the climb with power. Failure to lower nose and take what is coming can cause a stall or high sink. You are basically climbing near best glide, so you can't afford to hold the nose up. Push the nose down, flaps, and land in that forward quadrant either side of stright ahead depending on altitude.

If you have altitude to trouble shoot or maneuver fine, but plan "A" is land near straight ahead at min speed, flaps down, elect off, fuel off, belts tight. That may be all the time you have.

Think about that every takeoff. What are you going to do.

Van told a story in the RVator years ago of a new plane he flew off his grass field in Oregon. He took off in the opposite direction than he had first planned based on his brothers advice who was visiting. His brother pointed out the other direction, even with a slight tailwind, had more off field options. Guess what. The engine lost powered and the field, off the side of the runway end, saved the day.

[IowaRV9Dreamer]

Mel - I experienced carb ice on takeoff this summer in an old Continental powered 150. I usually fly 172s with a Lycoming and I initially had no idea what was going on, I thought it was an ignition problem. I think the weather was mid 50s and very humid, but no precip or clouds/fog.

Since I was geting enough power to keep climbing (really slowly) I elected to not touch anything until I got to 1000 AGL, which took a long time. I was in rurual Iowa so there were lots flat empty spaces around. At 1000' I pulled carb heat which made it run even roughter for a while until the power came back.

This is why I'm so intereted in carb heat in my -9A

BTW- I really like your posts, very informative, thanks!

[n5lp]

Originally Posted by rv6ejguy

...High descent rates at airspeeds just above the stall can exceed 1500 fpm (25 fps) with no energy left to flare. Spinal injury is almost certain as a minimum. Landing gear intrusion into the cockpit on A models is also very likely due to the shearing of the retention bolts. Ask me how I know.

Never be tempted to stretch the glide. Maintain 85 knots down to an early flare and probably use no or half flap as elevator authority with full flap and zero power is severely reduced.

Ross, I think we would agree that it is desirable, in an engine out situation, to land with as little downward and forward speed as possible. I would make different choices in my particular airplane, that is an RV-6/0-360/Sensenich metal fixed pitch. You seem to be running a Subaru engine, which may account for some of the differences.

In my airplane, that may be a more typical RV, things are different. First I would agree that the sink rate would get too high at too low a speed but I have found that 70 knots is more than adequate, in my airplane, for a perfectly normal flare, with the engine shut off and the propellor stopped. It stops at from 60 to 70 knots, so either it stops during the approach or during the flare. With a constant speed prop, I would likely use a bit faster speed, at least unless I had experimented and found that that prop will also stop at a similar speed.

Another difference is that I would use full flaps. I'll take every knot I can get in an emergency off-field landing. I have found, under every loading, that I have way more than enough elevator authority, even with no engine power. I wonder if that difference may have something to do with CG position?