Unsafe at any speed… Philip and a piston twin

It is almost impossible to insure or to give away a piston-powered twin-engine airplane these days. The oft-stated rule is that, in the event of an engine failure, “the second engine takes you to the scene of the accident”. Engines tend to fail shortly after takeoff when the pilot is busy, the airplane is slow, and the ground is going to come rushing up if swift action is not taken to feather the propeller (feather = turn the propeller blades so that the edges face the wind and it doesn’t create a huge amount of drag on one wing). When an engine quits, the pilot is supposed to push up the two mixture controls, the two prop speed controls, the two throttles and then make sure that the gear and flaps are up. After that it is identify and verify the dead engine by pulling back the throttle and seeing that there isn’t any yaw. Finally one is supposed to pick the correct prop speed control from among the six power levers and pull it back to feather. I thought I’d done just this and was a bit surprised by the fact that the airplane was yawing as I pulled the lever back. I kept pulling. My instructor, Jim Henry, is normally the soul of cool and calm. He jumped out of his seat and pushed my hand out of the way. “Maybe you shouldn’t pull back the mixture on the good engine.”

Ooops. One lever too far to the right. We were up at 3000′ above the ground, so there was no real hazard, but now I’ve learned why the average engine failure in a twin isn’t managed very well by the pilot. It really may be beyond the capabilities of the typical pilot. Turbine-powered airplanes, by and large, don’t ask pilots to be this good. On a King Air, a dead engine’s prop will feather itself and some rudder boost will be applied as well. On a turbojet, there isn’t a concept of feathering.

I’m ready for my multi-engine instructor checkride, but I might be kidding myself if I said I was ready to handle a real engine failure shortly after takeoff in a piston twin.

12 thoughts on “Unsafe at any speed… Philip and a piston twin

  1. Of course, this is what the Adams people have been saying for some time as well, although I know you are not a fan of that aircraft. So where do you go if you want that 2nd engine for “safety”, and you aren’t shopping in the 7 figure range?

  2. You need to fly a lot, until you don’t so much fly the plane as wear it. Then you need recurrent training at a place where they will really challenge you.

    As for not being able to give them away, try me. I’ve seen a lot of ice twins left to rot, and they are too far gone, but if I could get hold of one not too far gone I would bring it back to airworthiness. Sure, you can pick up a King Air for a very reasonable price compared to some asking prices on piston twins, but look at the fuel burn and what it will cost you bottom line per hour and you will cringe.

    It might be interesting for you to one day go to SimCom or Flight Safety and go through one of their training programs and report on their approach to safety and the wringer they put you through.

    Regarding losing an engine, the biggest problem is getting below Vmc, the speed where you have enough rudder control to counteract the yaw caused by asymmetrical thrust. When you are taking off you are very close to that so it only takes a blink of an eye of inattention at that point before you are in what is known as a “heap of trouble.”

  3. Will (or would) FADEC engine control retrofits help this problem? That does sound like a lot of levers to manage in a somewhat bad predicament. Are twin pilots forced to choose between trying to fly on one engine and cutting the second engine and looking for a good place to land?

  4. Ghengis: The DA42 has a FADEC but, in order to feather, the pilot is required to move his or her hand from the throttle area to the far left of the panel and toggle an engine control switch to “off”. Overall it is probably simpler than the Seminole, but certainly not foolproof.

    Peter: I’m not sure that I can blame lack of familiarity with the Seminole for my mistake. I only have about 15 hours in the machine in the last year or two, but they were all within the last week and I had an evil instructor turning off the fuel selector valve several times during each flight. So I am as current on engine failures as I am ever going to be, I think. It is sobering to realize that the peak of my capabilities is still not enough to handle a real emergency on climb-out.

  5. I think we’ve all done similar things at one point. I retracted (instead of extended) flaps on base, was reminded by my awesome CFI that this would probably not bode well for our lifespan, and learned to avoid that mistake in the future by momentarily making sure I’m flipping it in the right direction.

    Better to learn from the mistake at 3000′ and an instructor in the right seat than alone on takeoff.

  6. Your statement of “Engines tend to fail shortly after takeoff” is not correct. They are more likely to in cruise because that is where most of the time is spent. However, as you have trained, these failures are not a major event. In fact most airplanes on autopilot will correct the heading change by turning into the good engine (try it sometime). You have plenty of time to work slowly to identify the problem and shutdown the correct engine. You then can fly to the airport and land safely. Unless you forget that you have one less propeller disk to slow you down after you land and go off the end of the runway because you did not fly the proper approach (not that different from when both are running). The reason you hear most about failures on takeoff is that a engine failure in flight does not even need to be reported if no accident is involved.

    Section: 830
    “Engine failure or damage limited to an engine if only one engine fails or is damaged, bent fairings or cowling, dented skin, small punctured holes in the skin or fabric, ground damage to rotor or propeller blades, and damage to landing gear, wheels, tires, flaps, engine accessories, brakes, or wingtips are not considered “substantial damage” for the purpose of this part.”

    Actual engine shutdowns on takeoff have been eliminated during training. Only simulated loss of power is used. If you remember to first maintain airspeed and then heading, you should have plenty of time to not rush through the shutdown. Twins will climb great on two engines so you will probably be higher than you would in a single if the engine fails at the same time after takeoff. My first multi instructor had a good piece of advice – “If you are unsure of what to do, just turn them both off and land straight ahead as you would have done in a single engine airplane.”

    Remember that a good landing is one where you can walk away from it, a great landing is where you can use the airplane again.”

  7. Tom: “Engines tend to fail shortly after takeoff” was intended to communicate the fact that, per-minute, the engine is much more likely to fail right around takeoff when it is being asked to produce 100% power and might not be fully warmed-up. By the time you get to cruise, if the engine has been working it is pretty likely to continue working. Of course, you are right that many more hours are spent in the cruise so the best guess as to when an engine will quit is presumably somewhere in the cruise.

  8. Lycoming suggests otherwise on ongine failures on takeoff. Of course they make the things and have a vested interest.

    http://www.lycoming.textron.com/main.jsp?bodyPage=support/publications/keyReprints/operation/oldWivesTales.html

    “A letter which recently came from a Flyer reader takes this one step further. First it appears that there are many who continue to repeat this tale. This caused our reader to delve into the subject a little deeper – perhaps a little more scientifically than I did. Our reader studied a computer readout which had data on incidents of engine failure over a recent three year period. Based on the material in that report, this reader concluded that engine failures during takeoff are quite rare, and that failures during cruise are far more common. This does seem logical since the engines of fixed wing aircraft run a majority of their operating life in the cruise power range.

    Our reader also had a very believable theory about how this tale may have gotten started. He wrote, “It seems likely to me that this idea got started when twin engine flight instructors would simulate an engine out during takeoff – right about the time that the student put his hand on the prop control to reduce power…. Gradually the idea was propagated that this was the most likely time for an engine failure, when in reality it was a likely time for an instructor to simulate a failure.”

    From these two searches for justification – with none being found in either case, I believe it is fair to conclude that “the idea of an engine failure being most likely to occur at the first power reduction after takeoff” is in fact an old wives tale. For the sake of safety, lets stop repeating this false tale and start promoting the idea that we should be ready to deal with power failure at any time.”

    As you point out, an ounce of prevention (warming up the engine and a good runup) is better than a pound of cure. It mentions fixed wing aircraft but there are not that many engine failures in helicopters on takeoff and it is not a required demonstration to get a license. A hovering autorotation is not at all the same. Most accidents on takeoff in helicopters are caused by running into things. Robinson has a good, yet brief, runup procedure and they derate the engine to less than the full power it could produce.

  9. The risk of shutting down the wrong engine is why the Navy requires verbal confirmation of each step of the shutdown procedure between pilot and copilot. Also, not all turboprops autofeather – a T-44 (military KingAir) doesn’t, and the failure mode of the engine may prevent it, the worst case being a commuter flight that went down several years ago in Georgia. Light twins certainly are the most dangerous and least forgiving type of civil aircraft.

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