Nurse or feather that engine??

[deemee boosgkee]

My CFII was playing ATC while I was doing some IFR work in a AST-300 sim configured as a Seneca. Just as I was entering a hold he assigned the right engine ran very rough and lost about 7 in of MP. I looked up and saw the oil T pegged and the oil P very low. I was torn on whether or not to shut it down or simply reduce the power. I decided to reduce the power and wait to see if it cooled. About 5 min later the oil T was now down to 20 deg shy of redline. I kept it running at reduced power and did a LOC app and broke out 100 above the MDA.

In this situation would it have been better to feather it and shut it down or to keep it running at perhaps 40% power while montoring it accordingly? On the one hand I never like to be in a hurry to shut down an engine unless its on fire or about to break off from severe vibration but on the other hand I wasn't crazy about keeping it running for fear that it would seize therefore not being able to feather it or that also keeping it running would risk further damage which might lead to a fire.

Also I was flying over near SL terrain so the MEA's were well below the SE ceiling even in a measley Seneca!!

Keep her running or put her to bed? What's say you??

 

[siegelaviation]

My CFII was playing ATC while I was doing some IFR work in a AST-300 sim configured as a Seneca. Just as I was entering a hold he assigned the right engine ran very rough and lost about 7 in of MP. I looked up and saw the oil T pegged and the oil P very low. I was torn on whether or not to shut it down or simply reduce the power. I decided to reduce the power and wait to see if it cooled. About 5 min later the oil T was now down to 20 deg shy of redline. I kept it running at reduced power and did a LOC app and broke out 100 above the MDA.

In this situation would it have been better to feather it and shut it down or to keep it running at perhaps 40% power while montoring it accordingly? On the one hand I never like to be in a hurry to shut down an engine unless its on fire or about to break off from severe vibration but on the other hand I wasn't crazy about keeping it running for fear that it would seize therefore not being able to feather it or that also keeping it running would risk further damage which might lead to a fire.

Also I was flying over near SL terrain so the MEA's were well below the SE ceiling even in a measley Seneca!!

Keep her running or put her to bed? What's say you??

Owning and operating a Seneca II, I would have shut it down. If terrain isn't an issue and you don't have to worry about a missed/approach or go-around, a precautionary shut down would be wise. It doesn't take very long to get some nasty damage!

Michael

 

[CAVOK69]

It is easy to say what we would do in your position, having not been there!

But since you asked for advice, I'll give it.

Unless I suspected fuel contamination or terrain was an issue, or perhaps on the last couple 100 feet of a real instrument approach, I would have shut the engine down. You never know what could be the outcome of the engine coming apart in flight. Safer to declare an emergency, shutdown, get on the ground and ask questions later.

But it seems like what you did worked also. Had the engine lost all oil quantitiy then reducing the power setting would only delay the outcome shortly.

 

[AC560]

If you are losing oil pressure good chance the engine is going to feather on its own and make the decision for you. Best to be prepared either way.

 

[minitour]

If I'm losing oil pressure, I'd rather feather it myself than have it seize up on me all of a sudden...yes I know how a CS prop works and it should feather, but think of all of those squat switches that should keep the gear from coming up.

Aside from that or a fire, if it's giving me some power, I'm all for keeping it running especially in a piston twin.

JMHO

-mini

 

[svcta]

Maybe it's the jet operator in me, but maybe not......If it's running and not coming apart save it in case you do need it. Maybe especially in a seneca.

You got the temp down by reducing a bit of power and were set up to get it on the ground soon. You know you've got a situation that requires you land. Nurse the engine home. Precautionary shut downs are something that I think are best saved for turbines. Only because most turbine powered a/c are perfectly capable or flying just fine with one engine, and if they develop a problem it's usually serious.

Advice: Do not ever fly the airplane like you own it and have to pay for things. Even if you do. (when it comes to emergencies)

 

[svcta]

stupid internet. Double posted.

 

[unreal]

The way I see it, there's probably a pretty good reason why the engine just suddenly started losing oil pressure and running rough. I'd be looking at the root causes, which includes the possibility of an oil leak. With a high engine temp and oil possibly leaking into places it shouldn't be, I'm shutting that sucker down. Better to have to deal with flying a single-engine approach than dealing with an in-flight fire, or best case, an engine seizing up.

 

[deemee boosgkee]

Owning and operating a Seneca II, I would have shut it down. If terrain isn't an issue and you don't have to worry about a missed/approach or go-around, a precautionary shut down would be wise. It doesn't take very long to get some nasty damage!

Michael

The possibility of having to go missed because of LIFR contributed to my decision to keep it running. Lets say ATC gave me a bad vector right onto the marker while keeping me high and I had to go missed. My rationale was that I wanted as much power available in case this happened or if LLWS was encountered on the approach. (Usually occurs near W fronts and LL Temp inv which are usually the culprits of LIFR conditions.) While it was a hard decision whether to nurse or feather the engine, it was an easy decision fly the plane, maintain control and ask for vectors to the nrst suitable airport.

If it had been a turboprop or jet my decision would have been to secure it since they rarely have the issues of SE performance that piston twins do. Additionally, if I had shut it down I was increasing the chances (albeit slightly) of the other engine quitting because it would have run hotter due to the higher power needed to maintain altitude.


It disturbs me that scenarios like these are rarely taught when getting a ME rating. It seems in training that all the abnormal and emergency scenarios are clear cut and the engine failures sudden. The students then become programed and canned responses are the norm. Little emphasis is given to less clear cut situations that require a lot of deductive reasoning and many steps before making a decision. Luckily I am aware of this shortcoming in training and asked my CFII to give me emergencies in the sim that are not clear cut. For that I am grateful!


Thanks everyone for the feedback.

 

[svcta]

You made the right choice.

High oil temp or an engine running hot because of an obvious lubrication problem will not generate hear sufficient to start a fire.

Props feather a little more matter-of-factly than micro switches and old wires not preventing an inadvertent gear retraction. There's no 'system' to it; it's the laws of physics at work.


In a recip, in my opinion(most of them), there is almost no such thing as a precautionary shut down.

Clear weather and daylight would possibly generate a different response. But given the scenario, I'm sicking to my answer.

 

[AC560]

The possibility of having to go missed because of LIFR contributed to my decision to keep it running. Lets say ATC gave me a bad vector right onto the marker while keeping me high and I had to go missed. My rationale was that I wanted as much power available in case this happened or if LLWS was encountered on the approach. (Usually occurs near W fronts and LL Temp inv which are usually the culprits of LIFR conditions.)

The other end of this though is when you pull the power and start down the G/S the oil pressure is going to drop even further. Do you really want to be in the soup, on the ILS heading down, and have the engine pop into feather? It is one of those questions which is really hard to answer. But personally I think it is better to have a known situation then an unknown situation. If you shut the engine down you don't have to worry about it, leave it running and you have all kinds of things to worry about (is it going to feather, seize, burst into flames, etc). Obviously if it isn't going to climb on one or a needed system (vacuum pump, hydraulics, etc.) is on the damaged engine then you really don't have the choice.

 

[svcta]

Unless the you pull the power back enough to get the props out of govern, which I think is unlikely, the oil press will remain the same as it would at cruise or climb. Constant speed.....if the motor's turning at XXXX RPM it makes the same oil press regardless of MP.

Also, remember that in the original post he stated that the temp cooled down with reduced power setting. Keep it running.

 

[CAVOK69]

I see both sides of this for surer. But Ill stick to my answer as well, if I see oil pressure steadily dropping and temp above redline, unless I was in IMC/Approach area or terrain was an issue, I would shut it down. Yes it is supposed to feather, but a seizure could be much worse than shutting it down on your own. There is no clear cut answer to this situation, that is what you have the piece of paper in your wallet for that says you are qualified to be PIC and make the tough decisions.

The reason this sort of thing is not commonly tought is b/c there is no clear cut way to teach judgement or common sense. This is something that you will develope as a pilot and it sounds like you have already developed a pretty good sesne of judgement.

 

[svcta]

Funny, people are giving answers that are not related to the scenario presented.

He said: IMC, temp. problem corrected with reduced power setting.

To the original poster:

You did the right thing in this case, IMO. You sound as if you have the right idea about not being too quick to make a decision about things unless something's on fire or breaking off of the a/c. You'll learn as time goes by that in most cases the worst thing that a pilot can do is make snap decisions. Take all the time you need to sort through your problems.

In the situation you mentioned you handled it perfectly. Corrected the problem and carried a running engine until you no longer needed it(you got on the ground with it). Swell.

I had a sim instructor once that I was discussing fires with on a type ride. He was an older guy that flew for some big carrier back in the days of 3 person crews(as the norm). He was saying that their procedure for an engine fire was first for every crew member to take the following steps:

Crewmember 1. Hey, (sip coffee) that engine's on fire.
Crewmember 2. Yep, (sip coffee) it is on fire.
Crewmember 3. Man, (sip coffee) that thing really is on fire.

Then do something about it. I think this was in the early days of CRM and trying to engineer the cowboys of days past out of the cockpits. But it illustrates a great point. Never be in a hurry.

 

[Morettis]

The way I see it, I've got a deal with the plane to not hurt it, and it's got a deal to not try to kill me.

If an engine starts running like crap, it's already trying to kill me, so I could care less about runnin that engine into metal shavings.

I actually had this same situation happen to me in a 402. Oil pressure was on the low side taking off and in the climb out it came up and then started dropping off. after about 7,000 ft I started losing manifold pressure because the low oil pressure wouldn't keep the wastegate on the turbo closed. so I just pulled the power back on the dying engine and got vectors to an ILS at a nearby airport to land.

If you shut the engine down, it's gone for good. if you leave it running you at least have the option to use whatever you can get out of it if you need to. If for some reason the ******************** hits the fan and you have to go around, you're really going to want that 2nd engine even if it's just for a few seconds to get leveled off and accelerate into a climb before it craps out.

Who cares if it seizes? it should still feather.

 

[MauleSkinner]

Funny, people are giving answers that are not related to the scenario presented.

He said: IMC, temp. problem corrected with reduced power setting.

He also said: rough running engine, loss of MP, low oil pressure. Seems to me that's part of the scenario, too.

Personally, if the Oil Pressure continued to drop, I'd shut it down. If it stayed within limits, I'd keep it running if I thought I needed it AND I didn't think it would get worse at a critical time. I'm too lazy to prove that I'm a good enough pilot to shut it down and feather it within 500 feet of the ground on an ILS

Who cares if it seizes? it should still feather.

If it siezed, wouldn't the feathering pins extend, preventing it from feathering?

Fly safe!

David

 

[svcta]

poof...

 

[minitour]

If it siezed, wouldn't the feathering pins extend, preventing it from feathering?

Fly safe!

David

You'd think so.

-mini

 

[svcta]

It should feather. The engine will continue to turn even without a drop of oil for a period of time. That will keep the pins retracted and with no oil press. to maintain blade position it should go right on back.

 

[svcta]

He also said: rough running engine, loss of MP, low oil pressure. Seems to me that's part of the scenario, too.

You're right. But they wouldn't affect my answer at all.