Engine Chip Warning
Thread Starter
Join Date: Jul 2003
Location: Malaysia
Posts: 51
Likes: 0
Received 0 Likes
on
0 Posts
Engine Chip Warning
On a twin engined helicopter flying offshore, would you carry out an inflight shutdown of an engine with a chip warning light? Let's assume all other engine parameters appear normal. The Emergency Checklist says "recycle circuit breaker, if light remains on, shutdown engine".
Depends.
Are you on yur outward trip or homeward? Are you forced to land on a platform to get gas? (Leave it at idle, bring it on line for the landing, expect the worst) or just heading for a VMC trip to a runway?
Use your noggin, tempered with the advice from the flite manual. Doing a word-perfect checklist and splashing into the sea isn't as good as maybe wrecking the engine and making it home safely.
Are you on yur outward trip or homeward? Are you forced to land on a platform to get gas? (Leave it at idle, bring it on line for the landing, expect the worst) or just heading for a VMC trip to a runway?
Use your noggin, tempered with the advice from the flite manual. Doing a word-perfect checklist and splashing into the sea isn't as good as maybe wrecking the engine and making it home safely.
It depends whether you are IMC or VMC.
If IMC I would take the engine back to idle and try to get VMC.
If VMC I would shut it down. You shouldn't be in the situation where you have performance, OEI landing site or other concerns that would prevent you from shutting it down. You could always re-start the engine for the landing if you need to though.
If IMC I would take the engine back to idle and try to get VMC.
If VMC I would shut it down. You shouldn't be in the situation where you have performance, OEI landing site or other concerns that would prevent you from shutting it down. You could always re-start the engine for the landing if you need to though.
Join Date: Apr 1999
Location: vocation
Age: 57
Posts: 202
Likes: 0
Received 0 Likes
on
0 Posts
The tricky thing, (if you left the engine running, and it went bang), would be explaining to the "subsequent board of enquiry", as to why you didn't follow the emergency checklist.
As we all know, in aviation there is a fine line between "well done", and "what did you do that for?"
As we all know, in aviation there is a fine line between "well done", and "what did you do that for?"
Join Date: Jul 2003
Location: AUSTRALIA
Posts: 31
Likes: 0
Received 0 Likes
on
0 Posts
As "ATN" asked, It depends on what you are flying?
Is there a history?
Where are you going?
IFR vs VFR?
Does fuel play a part?
etc... etc... etc...
Its time to use all of that valuable training.
Also as the cynics say "If you have a 50:50 chance of making the right decision there is a 90% chance you'll make the wrong decision!"
Is there a history?
Where are you going?
IFR vs VFR?
Does fuel play a part?
etc... etc... etc...
Its time to use all of that valuable training.
Also as the cynics say "If you have a 50:50 chance of making the right decision there is a 90% chance you'll make the wrong decision!"
Thread Starter
Join Date: Jul 2003
Location: Malaysia
Posts: 51
Likes: 0
Received 0 Likes
on
0 Posts
I see that there is no correct answer to this.
Assume you are outbound to the rig in VMC and have a light payload and lots of fuel. The helicopter is an S61 and so, a single engine landing offshore is out of the question.
Would you follow the checklist or would you apply your experience?
Assume you are outbound to the rig in VMC and have a light payload and lots of fuel. The helicopter is an S61 and so, a single engine landing offshore is out of the question.
Would you follow the checklist or would you apply your experience?
Howcanwebeexpectedtoflylikeeagles
whensurroundedbyturkeys
Hello Gabra1 from a Pprune newbie.
If your Emergency Checklist says;
"recycle circuit breaker, if light remains on shutdown engine"
why would you want to do otherwise under the circumstances you quote? What "experience" would cause you not to follow the checklist? I would maybe understand your inference if you were talking about a fire warning when "experience" shows that 99% of fire warnings are false.
But even with a fire warning in the circumstances you quote, I would probably shut down the engine and RTB if for no other reason than the fact I would have lost the fire warning system for that engine.
I know that chip warnings can be triggered by metalic dust (do you have a fuzzburn facility?) but a mechanical breakdown of a bearing or similar can be very expensive if not dangerous if allowed to develop. In my mind, a single engine RTB is no big deal. I can't remember ever having an engine chip light coming on during my time on the S61 many years ago - but maybe we didn't have chip lights fitted in those days.
If your Emergency Checklist says;
"recycle circuit breaker, if light remains on shutdown engine"
why would you want to do otherwise under the circumstances you quote? What "experience" would cause you not to follow the checklist? I would maybe understand your inference if you were talking about a fire warning when "experience" shows that 99% of fire warnings are false.
But even with a fire warning in the circumstances you quote, I would probably shut down the engine and RTB if for no other reason than the fact I would have lost the fire warning system for that engine.
I know that chip warnings can be triggered by metalic dust (do you have a fuzzburn facility?) but a mechanical breakdown of a bearing or similar can be very expensive if not dangerous if allowed to develop. In my mind, a single engine RTB is no big deal. I can't remember ever having an engine chip light coming on during my time on the S61 many years ago - but maybe we didn't have chip lights fitted in those days.
Join Date: Aug 2002
Location: Afrika sometimes
Age: 68
Posts: 219
Likes: 0
Received 0 Likes
on
0 Posts
If your emergency checklist is accurately based on the AFM emergencies section why would you not follow it? As Hugh Martin says, if your chip light has been brought on by the breakdown of a bearing, you keep the engine running and it is subsequently damaged, your company is, very rightly, going to be extremely pi**ed off with you. If the engine were damaged and an accident resulted, you would probably have negated your aircraft insurance and could be held personally liable.
Presumably, whether flying offshore or not, if you are on a public transport flight, you would still have your Class One en-route performance on the other engine, and would have already calculated that the combination of speed and fuel-burn for your aircraft would be sufficient to take you back to a suitable place for a safe single-engined landing?
Not all helicopters require you to shut-down an engine with a chip light, but if they do, it's usually for a very good reason
Presumably, whether flying offshore or not, if you are on a public transport flight, you would still have your Class One en-route performance on the other engine, and would have already calculated that the combination of speed and fuel-burn for your aircraft would be sufficient to take you back to a suitable place for a safe single-engined landing?
Not all helicopters require you to shut-down an engine with a chip light, but if they do, it's usually for a very good reason
You're going to feel pretty stupid when the engine seizes at 50,000 rpm!
One interesting point to bear in mind with types where the advice is to bring the engine back to idle, is that the fuel burn will be greater than on single engine. On my current type the advice is bring it to idle and if the engine parameters stay normal reinstate it for the landing. Meanwhile you will have used single engine fuel burn and TAS coupled with an engine doing no useful work and burning 35-40 kg/hr. Could make quite a difference on a long leg.
One interesting point to bear in mind with types where the advice is to bring the engine back to idle, is that the fuel burn will be greater than on single engine. On my current type the advice is bring it to idle and if the engine parameters stay normal reinstate it for the landing. Meanwhile you will have used single engine fuel burn and TAS coupled with an engine doing no useful work and burning 35-40 kg/hr. Could make quite a difference on a long leg.
Shut it down in accordance with the drills and only restart if ESSENTIAL for landing. Can't see why there should be a debate - trying to second guess the cause of the chip light is like playing russian roulette, you might get lucky but then again......
Thread Starter
Join Date: Jul 2003
Location: Malaysia
Posts: 51
Likes: 0
Received 0 Likes
on
0 Posts
Thanks for your views.
In this particular case, the PIC followed the AFM checklist and OM EOP, shutdown the effected engine and did a single engine run on landing at an airfield. No problem.
My question is, why is this type of emergency handled differently on different types of helicopters? Surely the sensible thing to do here is to get into single engine configuration, bring the "bad" engine to ground idle and monitor it as you go along. If it starts to make a funny noise, shut it down. What if the good dong decides to quit for whatever reason?
What's the procedure for single engine helicopters? Shutdown as well?
What I am trying to establish through this forum is whether there is a case to review the EOP for such emergencies or whether we should take what the manufacturer says without question?
More comments please!
In this particular case, the PIC followed the AFM checklist and OM EOP, shutdown the effected engine and did a single engine run on landing at an airfield. No problem.
My question is, why is this type of emergency handled differently on different types of helicopters? Surely the sensible thing to do here is to get into single engine configuration, bring the "bad" engine to ground idle and monitor it as you go along. If it starts to make a funny noise, shut it down. What if the good dong decides to quit for whatever reason?
What's the procedure for single engine helicopters? Shutdown as well?
What I am trying to establish through this forum is whether there is a case to review the EOP for such emergencies or whether we should take what the manufacturer says without question?
More comments please!
Join Date: Oct 2003
Location: Over here
Posts: 1,030
Likes: 0
Received 0 Likes
on
0 Posts
I don't think you should ever take what anyone says without question, but you need a very good answer before you do something different from what is published. And the chief pilot will be asking for that answer very soon afterwards.
Avoid imitations
Join Date: Nov 2000
Location: Wandering the FIR and cyberspace often at highly unsociable times
Posts: 14,574
Received 422 Likes
on
222 Posts
I can't see a case for bringing the engine to idle rather than shutting it down completely. If a bearing is running out, a 25,000 rpm idle might be just as damaging as 50,000 plus rpm. By leaving the engine at idle, when it is providing no torque and just burning fuel to self-sustain, you are achieving nothing.
Your sick donkey might subsequently seize before you need it for landing. Had you shut it down for transit and subsequently restarted it, it is more likely to be usable for when you really need it.
In the event, my own preference would ideally be to transit single engine, restart the engine for landing if required, but not rely on it and carry out an OEI profile just to be doubly safe. Having the second engine running for landing will prevent unnecessarily busting a limit on the good engine, which would be a great shame if the chip turned out to be a very minor thing.
Unless, of course, the Flight Manual or your company policy says otherwise. The time to change the checklist IS before you have to do it for real, which I think is why Gabra1 is asking.
Your sick donkey might subsequently seize before you need it for landing. Had you shut it down for transit and subsequently restarted it, it is more likely to be usable for when you really need it.
In the event, my own preference would ideally be to transit single engine, restart the engine for landing if required, but not rely on it and carry out an OEI profile just to be doubly safe. Having the second engine running for landing will prevent unnecessarily busting a limit on the good engine, which would be a great shame if the chip turned out to be a very minor thing.
Unless, of course, the Flight Manual or your company policy says otherwise. The time to change the checklist IS before you have to do it for real, which I think is why Gabra1 is asking.
Join Date: Apr 2003
Location: USA
Age: 75
Posts: 3,012
Likes: 0
Received 0 Likes
on
0 Posts
Having written the ER's for a couple of helos, I surely hope that all of us do what those procedures say, as a general rule.
The concept is simple, like the Hypocratic Oath, "Do no harm."
If it says shut down, do so unless you are driven to need that chipped engine and will go into the drink without it. If it says idle, do only that unless that pesky engine is doing something else that demands attention, like screeching or pulsating like it is going to get very angry if you keep it running.
Most of all chips are fuzz, to the tune of 95% or more (ppruner with real data, jump in) and most accidents are caused when pilots do something less than perfectly. To shut down an otherwise healthy engine for a non-fuzzburn chip light might be a pretty bad bet, unless the flight manual says shut it down.
Rule of thumb, half the engine noise is less than half the fun, don't shut down an engine unless asked to. If asked to, then do so.
The concept is simple, like the Hypocratic Oath, "Do no harm."
If it says shut down, do so unless you are driven to need that chipped engine and will go into the drink without it. If it says idle, do only that unless that pesky engine is doing something else that demands attention, like screeching or pulsating like it is going to get very angry if you keep it running.
Most of all chips are fuzz, to the tune of 95% or more (ppruner with real data, jump in) and most accidents are caused when pilots do something less than perfectly. To shut down an otherwise healthy engine for a non-fuzzburn chip light might be a pretty bad bet, unless the flight manual says shut it down.
Rule of thumb, half the engine noise is less than half the fun, don't shut down an engine unless asked to. If asked to, then do so.
Last edited by NickLappos; 19th Dec 2003 at 04:40.
Join Date: Jul 2000
Location: Haggisland
Posts: 56
Likes: 0
Received 0 Likes
on
0 Posts
It is common on a certain type of engine (made in Europe) for a brand-new recent-fit one to develop a 'harmless' chip light within the first few hours of use. To use this information though, you'd need to have the engine log book to hand.
You could always fit a HUM system and end up worrying needlessly over g figures and possibly suspect data. I think that there arn't many systems around that show a warning (a la S92) for impending doom, preferring to trust to luck, sorry, I mean traditional maintenance methods and correct emergency procedures.
You could always fit a HUM system and end up worrying needlessly over g figures and possibly suspect data. I think that there arn't many systems around that show a warning (a la S92) for impending doom, preferring to trust to luck, sorry, I mean traditional maintenance methods and correct emergency procedures.
212Man,
Did you not in a previous thread talk about developing a "conditioned response" in pilots during training for later use during emergencies? Why would the considerations you cite matter if pilots are to comply with these procedures as written in the RFM?
Also Nick ol' Buddy....the industry tends to skip over the concept that a single illuminated caution light labeled "Eng Chip" with absolutely nothing else being abnormal is a very much different situation from having secondary indications of a problem. That could be in the way of a history of chip lights, fuzz accumulation, actual chip accumulation, recent engine change for an engine making metal and no change of the associated oil cooler.
I see the engine chip situation from this perspective....
Light Only....No other indications abnormal/No history of trouble
Light On...completely spurious indication (wiring fault maybe)
Light On...build up of fuzz
Light On...small hairs or slivers
Light On...small chips or flakes
Light On...real chip
Light On...chip with part numbers
Light On...Large Metal bits....ugly noises....whole part numbers
Until we get down to the very bottom of that list.....leaving the engine run can do no real harm. Once again...we are talking about a caution light only and no other indications.
I firmly believe in leaving the thing run....keeping an eye and ear open.....and until a second indication occurs....leave the engine running at normal speed. Immediately upon suspecting a second indication...oil pressure/temperature change, vibration change, sound change, change in smell of the oil from the vents/breathers....fluctuations in the gauges....make a decision as to shut the engine down or not....but not before then. Much better to divert to a safe landing site on two engines and land there on two rather than risk having an engine failure on the remaining engine or making a single engine landing in marginal conditions.
Did you not in a previous thread talk about developing a "conditioned response" in pilots during training for later use during emergencies? Why would the considerations you cite matter if pilots are to comply with these procedures as written in the RFM?
Also Nick ol' Buddy....the industry tends to skip over the concept that a single illuminated caution light labeled "Eng Chip" with absolutely nothing else being abnormal is a very much different situation from having secondary indications of a problem. That could be in the way of a history of chip lights, fuzz accumulation, actual chip accumulation, recent engine change for an engine making metal and no change of the associated oil cooler.
I see the engine chip situation from this perspective....
Light Only....No other indications abnormal/No history of trouble
Light On...completely spurious indication (wiring fault maybe)
Light On...build up of fuzz
Light On...small hairs or slivers
Light On...small chips or flakes
Light On...real chip
Light On...chip with part numbers
Light On...Large Metal bits....ugly noises....whole part numbers
Until we get down to the very bottom of that list.....leaving the engine run can do no real harm. Once again...we are talking about a caution light only and no other indications.
I firmly believe in leaving the thing run....keeping an eye and ear open.....and until a second indication occurs....leave the engine running at normal speed. Immediately upon suspecting a second indication...oil pressure/temperature change, vibration change, sound change, change in smell of the oil from the vents/breathers....fluctuations in the gauges....make a decision as to shut the engine down or not....but not before then. Much better to divert to a safe landing site on two engines and land there on two rather than risk having an engine failure on the remaining engine or making a single engine landing in marginal conditions.
Join Date: Apr 2003
Location: North of the Border
Posts: 149
Likes: 0
Received 0 Likes
on
0 Posts
I was under the impression that this mod was introduced after the loss of a S61 last year in the UK. If I remember right, the No 5 engine bearing failed, causing a fire which quickly spread to the other engine and the back of the gearbox. Fortunately they managed to get the a/c on the ground within 90 secs of the first engine fire warning, just before they lost all hydraulics. A couple of minutes later the gearbox fell through the roof of the cabin. All the guys got out without injury.
I know exactly what my reaction would be to an engine chip warning - exactly what it says on the EOP!
I know exactly what my reaction would be to an engine chip warning - exactly what it says on the EOP!
Crashondeck......did they get an engine chip warning or merely have a catastrophic failure followed by an uncontained turbine failure and subsequent fire with an associated fire warning?
Blind obedience to a checklist will kill you....ask some 212 TRE's that "died" in a simulator a while back. The failure occurred prior to TDP/CDP on takeoff from a runway at a large airport. As the nose rotated downwards to initiate the takeoff...the main rotor overspeeded. The Flying Pilot (the senior of the two)...per his brief and company policy...elected to abort the takeoff and land back. Alas, it was a high side governor failure that did not respond to throttle....and while the two sat there trying to digest what was going on....the sim growing tired of Nr in excess of Warp speed....for what seemed like an intermiable time....provided them with a catastrophic main rotor failure as punishment for failing to reduce the Main Rotor Nr to within tolerable limits.
The more effective approach to that problem would be to load the main rotor by means of collective, roll the throttle back on the affected engine, upon discerning no reaction, the solution would be to continue the takeoff, climb to a safe altitude, maintain Nr within a safe range, and upon reaching a safe altitude, select governor to emergency, and regain control of the engine. If the selection of emergency governor fails to cure the problem, then shutting the engine down by means of the throttle release or either pulling the T-handle or shutting the fuel valve would be necessary....followed by OEI flight to a safe landing area.
But all that is not in the RFM...and as Nick Lappos will tell you....you cannot list every conceivable emergency procedure in the manual. That is why Pilots should be encouraged to think while confronting abnormal or emergency conditions in an aircraft.
Blind obedience to a checklist will kill you....ask some 212 TRE's that "died" in a simulator a while back. The failure occurred prior to TDP/CDP on takeoff from a runway at a large airport. As the nose rotated downwards to initiate the takeoff...the main rotor overspeeded. The Flying Pilot (the senior of the two)...per his brief and company policy...elected to abort the takeoff and land back. Alas, it was a high side governor failure that did not respond to throttle....and while the two sat there trying to digest what was going on....the sim growing tired of Nr in excess of Warp speed....for what seemed like an intermiable time....provided them with a catastrophic main rotor failure as punishment for failing to reduce the Main Rotor Nr to within tolerable limits.
The more effective approach to that problem would be to load the main rotor by means of collective, roll the throttle back on the affected engine, upon discerning no reaction, the solution would be to continue the takeoff, climb to a safe altitude, maintain Nr within a safe range, and upon reaching a safe altitude, select governor to emergency, and regain control of the engine. If the selection of emergency governor fails to cure the problem, then shutting the engine down by means of the throttle release or either pulling the T-handle or shutting the fuel valve would be necessary....followed by OEI flight to a safe landing area.
But all that is not in the RFM...and as Nick Lappos will tell you....you cannot list every conceivable emergency procedure in the manual. That is why Pilots should be encouraged to think while confronting abnormal or emergency conditions in an aircraft.
SASless
I would caution against using "a history of chip lights" as a guide for trouble shooting. From personal experience, this is like "the boy who cried wolf" story. We had a LTS101 let go 80nm offshore after having had a short history of electrical problem induced chip lights. If the book says shut it off ... then shut it off, if it says you can leave it at idle & use it for landing then I'd do just that. OEI condition (post CDP) should not be a big issue. If it is, then somthing has gone wrong at the planning stage.
I would caution against using "a history of chip lights" as a guide for trouble shooting. From personal experience, this is like "the boy who cried wolf" story. We had a LTS101 let go 80nm offshore after having had a short history of electrical problem induced chip lights. If the book says shut it off ... then shut it off, if it says you can leave it at idle & use it for landing then I'd do just that. OEI condition (post CDP) should not be a big issue. If it is, then somthing has gone wrong at the planning stage.