Engine failure...and restart

[Xcaliber]

You are piloting a recip twin along a relatively short 70 nm cross country. About 20 miles along the route, one of your engines fail. After doing your first quick emergency procedure (maintain directional control, full power, maintain Vyse, declare an emergency and let ATC know you'll be drifting down) and before feathering the engine, you decide to try to restart it, and sure enough, the engine comes back to life. Before the failure, you had no indications that anything was wrong. After the restart, the engine still does not seem to have any problems, at least any that you can see from the cockpit. Knowing that the engine had to have quit for a reason, what would you do?

Would you divert back to your departure airport, or keep going to the destination? Cancel the emergency with ATC, or keep it? Would it make a difference if the total distance was 300 nm, and the engine failed about 100 nm in? Would it make a difference if you were flying a turine instead of a recip?

For the sake of this scenario, assume both airports have the same services, ie. approaches, maintenance, fuel, ATC, etc. Also assume that you did not starve the engine of fuel, at least as far as you know (still plenty of gas in all tanks, no important valves closed, etc.).

 

[Mad Doggy Dog]

Lemme guess, in this scenario one was flying a Cessna 414 with tip tanks and engine nacelle tanks..............and screwed up the tank management?

Switch tanks and press on! .....Buy a Kingair-90.

Same for when you screw up the fuel in a Cessna 310 as well!



But seriously.....

I have never liked these types of questions, and I've never lked job interviewers who ask these "what if" questions, because there are too many variables not disclosed in the the question itself.

Well, whatever the reason for the engine failure, landing at the nearest suitable airport is the prudent thing to do. [That should be your canned answer during an interview.] Of course this leaves it up to you, the FAA and the lawyers to determine what "suitable" is. Suitable can be far away. [This is why aviation lawyers have jobs.] Keep the emergency in place unless you know for sure why the engine quit [switch tanks dummy!] I'd go back to my departure airport. That is where my car is..........and by then I'd be hungry for some In and Out burgers!

Now if you're on fire and there is a closer airport, [although within 20 nm you are splitting hairs,] that's another story!

Most engine failures are caused by fuel starvation.

Recip vs turbine should not make a difference.

If you are on a 300nm trip, chances are you'll be at a cruise altitude whereby it might take you 100 nm to run your emergency checklists, procedures and drift drift down; so pressing on is not out of the question.

 

[ctab5060X]

First off, you missed an important part of your quick emergency checklist...verify fuel...

Like MDD said, most engine failures are the result of fuel starvation, so that should be the first thing you check before securing the engine...sometimes all you do is swap tanks, open a valve, or turn on a boost pump and the engine roars back to life.

You stated that before feathering you decided to attempt a restart. Is the prop still windmilling? Or was it a sudden seizure? If it was windmilling, you are pretty much left with either fuel or fire. If you are certain you did not starve the engine of fuel and the mags are on, there is no sense in even trying to bring the engine back to life. Feather it, secure it, declare your emergency and get back on the ground. If it was a seizure or catastrophic failure, then it becomes a no brainer, feather, secure, etc...

If you are only 20 miles from your departure airport, and from your scenario, high enough to worry about drift down, you should have no problem getting back in. Declare an emergency, get back on the ground.

But my big question still is, why attempt the restart? Unless you can open up and look at the engine to verify that nothing is wrong, leave it shut down. How do you know that if you restart, the engine is not going to quit again? Once you have the engine shut down, feathered, and secured...leave it. If you don't feel that you can get back to your airport of departure, find somewhere else that is closer.

As for your question regarding the 300nm trip and being 100nm in, it all depends on the situation at the time. I currently fly a recip twin on a 330nm trip every night and our procedures for an engine failure change with the weather. Are there storms ahead, behind? If not storms, what about ceilings and visibility? Will I have to fly and approach? Do I have a bad headwind, tailwind? Are the MEAs higher or lower as we continue? How do the MEAs compare with our single engine service ceiling? All of this is stuff that should be thought of prior to your departure and not figured out once you lose an engine...no matter the length of the trip. There should be a well laid out plan of what to do when. For example...if I lose and engine prior to point A, I return to my destination ABC...engine failure past point A but prior to point B, I will divert to JKL...engine failure past point B, I continue to destination XYZ.

 

[Berkut]

Would you divert back to your departure airport, or keep going to the destination?

Back to departure.

Cancel the emergency with ATC, or keep it?

Keep it, but update them on the situation.

Would it make a difference if the total distance was 300 nm, and the engine failed about 100 nm in?

In that case, I would find a closer airport to divert to.

Would it make a difference if you were flying a turine instead of a recip?

Hmmm, hard to say. Probably not.

 

[Xcaliber]

Ok, maybe I should clarify a little bit. The scenario in this case isn't as much about the cause of the engine shutdown nearly as much as it is about the decision making process after the fact. For some unknown reason, the engine shut down (assume windmilling). And then it got restarted. Whether you did it, or it just restarted on it's own, it doesn't matter. You are now running on two engines, but are unsure of why it shut down in the first place (As I said in the original post, fuel starvation was not the cause, as far as you can tell from the pilot's seat. That's all the information you get! ). You are a third of the way along your route, have an open emergency with ATC, and now you are faced with the decision to divert or continue.

The reason I asked this question was a sim I did a few days ago. The guy running the sim gave me an engine failure in cruise. Based on the situation, there were a few different reasons I could come up with that could've caused the failure (ended up being the one I most expected...imagine that). A little while after doing my checklist, the engine came back. I still wasn't completely sure what caused the failure, but now I was faced with a decision I didn't expect...I had two working engines, with an emergency declared, 30ish miles back, 45ish miles to go, which airport do I go to?

 

[WalterSobchak]

You are piloting a recip twin along a relatively short 70 nm cross country. About 20 miles along the route, one of your engines fail. After doing your first quick emergency procedure (maintain directional control, full power, maintain Vyse, declare an emergency and let ATC know you'll be drifting down) and before feathering the engine, you decide to try to restart it, and sure enough, the engine comes back to life. Before the failure, you had no indications that anything was wrong.

In a recip twin without feathering the prop you don't need to restart it. Its already windmilling so switch tanks and throw a boost pump on it gets fuel it lives. You are in cruise so why go to Vyse? No reason for full power on the other engine in cruise and you shouldn't be drifting down. Why do a quick emergency procedure you are in cruise? Slow down and think. Make sure you have an emergecy before you declare one.

 

[FlyOrDie]

Would you divert back to your departure airport, or keep going to the destination? Cancel the emergency with ATC, or keep it? Would it make a difference if the total distance was 300 nm, and the engine failed about 100 nm in? Would it make a difference if you were flying a turine instead of a recip?

Is your departure airport good weather? Is your departure airport in high terrain? Does the departure airport have emergency services? Do you have high terrain between you and your destination? There's too many unknowns to make a decision about if you need to turn around or not. I think whether you're 3 miles or 300 miles into a trip you still need to weigh what the airport has to offer you as far as weather and approaches and what sort of terrain you have to cross to get there. I think of terrain in this situation as risk, the higher the terrain the higher the risk of death if you have to do a forced landing.

It would make a huge difference if you were flying a turbine because you wouldn't have had the random shut down and restart. As far as the engine coming back to life I'd be in favor of feathering and leaving it that way because you no longer know what's happening in that engine and you don't want to get yourself into a situation in which you no longer have the option of feathering.

I'd classify this question as a bad one because of the engine coming back to life. Feather it and leave it that way and fly the airplane like you're on one. The airplane's already cheated on you so it'll likely do it again. In the DC6 we're taught this philosophy "When on 4 think 3, when on 3 think 2, when on 2 think 1, when on 1 wish you didn't have 30,000lbs of crap in the back."

 

[ctab5060X]

Ok, maybe I should clarify a little bit. The scenario in this case isn't as much about the cause of the engine shutdown nearly as much as it is about the decision making process after the fact. For some unknown reason, the engine shut down (assume windmilling). And then it got restarted. Whether you did it, or it just restarted on it's own, it doesn't matter. You are now running on two engines, but are unsure of why it shut down in the first place (As I said in the original post, fuel starvation was not the cause, as far as you can tell from the pilot's seat. That's all the information you get! ). You are a third of the way along your route, have an open emergency with ATC, and now you are faced with the decision to divert or continue.

The reason I asked this question was a sim I did a few days ago. The guy running the sim gave me an engine failure in cruise. Based on the situation, there were a few different reasons I could come up with that could've caused the failure (ended up being the one I most expected...imagine that). A little while after doing my checklist, the engine came back. I still wasn't completely sure what caused the failure, but now I was faced with a decision I didn't expect...I had two working engines, with an emergency declared, 30ish miles back, 45ish miles to go, which airport do I go to?

I'm still confused here...you say that you did your checklist, but during this checklist you forgot identify, verify, feather? So, from what I am reading, you had an engine failure, ran your checklist, and just left the prop unfeathered, just windmilling away? Still further confused by you stating in your original post that "you decide to try to restart it" and your second post of "And then it got restarted"/"the engine came back". Which one was it? Furthermore, I don't see how the engine could "just come back" unless you left it windmilling and didn't feather and secure the engine. Guess I need a clarification of "a little while"...are you talking 30 seconds or 3 minutes? Considering the engine failure was at 20nm and you are now 30nm with two engines, I am guessing you are talking several minutes between checklist and the engine restarting.

But for now, I will go along with the situation of the engine coming back...

As I stated before, the decision on where to go in this situation is not something that is made at the time of the failure. It is a decision that is made before you even get in the airplane. If you have done proper preflight planning, then there is no need to worry about "which airport do I go to?" Your decision should already have been made. From what you have said so far, I would be returning to the departure airport, with an engine shut down and prop feathered.

 

[Screaming_Emu]

You are in cruise so why go to Vyse?

Sure there is. If you can't maintain altitude single engine then VYse will be your minimum sink speed.

No reason for full power on the other engine in cruise and you shouldn't be drifting down.

Maybe not full power. But if you're in cruise and can't maintain altitude single engine, then you'll want MCT to minimize your rate of descent.

 

[WalterSobchak]

Sure there is. If you can't maintain altitude single engine then VYse will be your minimum sink speed



Maybe not full power. But if you're in cruise and can't maintain altitude single engine, then you'll want MCT to minimize your rate of descent.

Why just assume you are drifting down? I've had 5 engine failures. Recip twins fly fine one one engine it's not a big deal if you manage it properly. The crankshaft failure had the quickest time from an indication to total destruction and I still had a good 20 seconds to pull the power and feather it as it gutted itself.

Still my point is there is no point for a restart in a piston twin with a windmilling prop. Change tanks, bam back to life.

 

[SoCalAprch]

Fak it, keep on going man thats why you have two engines right? In these situations I always ask myself "What would Chuck Norris do?"

Divert to the most suitable airport would be my canned reaction in a sim. They can't fail or criticize you for being by the book. The engine quit for no reason and is now running again. Well this could be a multitude of things including contaminated fuel and if that is the case then you don't want to dick around waiting for both of them to call it quits. Get it on the ground and take the crew car to go get some In N Out.:nana2: If you realize it was your own fault, most likely the case, and you fixed it then keep on going.

 

[taseal]

if I have 2 engines, and I loose one of them, and it comes back to life magically somehow. i'm going to assume there is some kind of problem, which might be contaminated fuel or electrical. in anycase, if this happened, I would go back to the airport. you never know whats going to happen next. I can't risk that.

I have gone back to the airport when the engine would make odd noises. I would no way continue (or turn back if its a longer trip) if I lost the engine, and it came back.

I would land somewhere reasonably close (20-30 miles at most) and get it checked out. if they say they can't find anything, then I would at least know that, and get going on my way.

remember, it never hurts to be on the safe side. not just in aviation, but in any situation.

 

[WalterSobchak]

it never hurts to be on the safe side. not just in aviation, but in any situation.

:yeahthat:Use protection!