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#4396147 - 12/21/17 11:42 PM Huey catches fire nearly every flight now  
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RhinoX55 Offline
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Fort Lauderdale, FL, USA
I had heard that there was some sort of update to the Huey model to add sensitivity to engine temp.

Now it seems ridiculously dangerous to fly. Like if EGT exceeds the green zone for more than a second or two, the helicopter bursts into flames and you crash instantly. No warning.

I set the helicopter to autopilot/level flight for an ingress across flat terrain. Apparently my AI co-pilot is not used to the update, either, because he caused the engine to catch fire and crashed the aircraft, also.

Last edited by RhinoX55; 12/23/17 09:04 PM.

"Airplanes are interesting toys, but of no military value."
- Ferdinand Foch, Supreme Commander of Allied Forces, WWI
#4397291 - 12/29/17 05:52 AM Re: Huey catches fire nearly every flight now [Re: RhinoX55]  
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Try using the autostart function and see if it still catches on fire.

You may be using an incorrect startup procedure which could be causing the EGT to be higher than it is supposed to. I never have EGT out of the green in my flights.

Also check if you have a controller that is pushing the engine throttle up? You're not supposed to be flying at 100% throttle nor 100% collective. If your throttle is overriding the governor it could be pushing the engine to 100% and that will definitely cause fires eventually.

#4405265 - 02/15/18 09:12 AM Re: Huey catches fire nearly every flight now [Re: RhinoX55]  
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S_Bartfast Offline
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South Australia
Just came across this thread as I am having the exact same problem.

Basically all seems fine, then all of a sudden the fire warning light illuminates, a siren sounds and all power is lost with no way to fly the aircraft. This happens in all the missions I've tried lately but currently I'm attempting to do the "Elbrus Rescue" mission again starting with a "Hot start".

Normally I slowly pull the collective up all the way then back it off a touch to prevent the "Underspeed" alarm from sounding then climb with a forward speed of 80kn, but this no longer works. Are you suggesting I should back the throttle off a little even with a "Hot start"? Kind of defeats the purpose of a hot start if you then need to reduce the throttle before taking off.

And by "EGT" are you referring to the gauge marked "EXHAUST"? Perhaps my setup is just lacking in awesomeness but I find that gauge extremely hard to read while in flight.

In any event I just tried yet another rescue attempt with the throttle set a little down from maximum and noted the "EXHAUST" needle is a little over the top of the green band but below the red mark and left yet another HU-1 in a smoldering heap on the side of that mountain. Any idea what is going on?

Last edited by S_Bartfast; 02/15/18 09:14 AM.
#4405268 - 02/15/18 11:02 AM Re: Huey catches fire nearly every flight now [Re: RhinoX55]  
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It sounds to me like both of you are trying to fly the helicopter as fast as possible, as heavy as possible, pulling as many g's as possible. That is why you're getting rotor rpm beeping in flight. That is never supposed to happen.

Look at your governor needle and the exhaust gas temp needle. I am betting that both of you have yours pegged all the time and if that's the case, engine fires are an obvious consequence. The rotor underspeed alarm only goes off when you're really abusing the helicopter, you're not supposed to ever get even close to hearing it while flying.

Can't say if it's an engine fire or a fire starting elsewhere but it's a direct result of abusing the helicopter, you're flying with too much collective and it's straining the engine and connected parts, causing the fire.

I suggest taking a look at the manual to get an idea of the suggested cruising speeds, and the max speeds for the huey. The airspeed indicator has big numbers written on it, but just because they're on the thing does not mean you're supposed to be able to achieve them in normal flight.

Use less collective, rely more on translational lift (Lift produced by flying forward, google it) instead of trying to add more and more collective. The engine fires will go away.

As for hot starts, I'm not sure why you're mentioning that - hot starts are caused by improper timing and startup procedures. If you're getting hot starts you should check the startup procedures once more. If it is a mechanical / random failure causing the hot start, IIRC the correct procedure is to cut the fuel immediately and allow the starter to keep cranking the engine to clear out the accumulated fuel and cool the engine. If you do hot start you may as well reload the flight as it's basically a catastrophic failure of the engine that requires a maintenance check if you don't want to risk dying in the air..!

#4405284 - 02/15/18 03:14 PM Re: Huey catches fire nearly every flight now [Re: VF9_Longbow]  
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S_Bartfast Offline
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Fair enough, I'll give a go with only 3/4 collective and see how it goes.

By the way, the objective of the "Elbrus Rescue" mission is to get to the top of the mountain as quickly as possible. The mission starts with a radio call saying a Mi8 has crashed at the top of the mountain and that there are people dying up there. So you need to race up to the top of the mountain as quickly as possible in order to save the pilot and a few others. I had thought the best climb rate was achieved with a forward velocity of 80kn and the collective cranked but I'll try a less aggressive climb if that's what's required now.

By "Hot start" I just mean selecting the "Hot" option at the beginning of the mission such that the mission starts with the heli already running and ready to take off, as apposed to starting "Cold" (and dark) where you need to go through the full startup procedure.

#4405421 - 02/16/18 09:26 AM Re: Huey catches fire nearly every flight now [Re: RhinoX55]  
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Ah I see what you mean - I think that's engines hot and running. A hot start is actually when fuel pools in the engine then catches fire and kills the engine.

You just need to keep your eye on the EGT gauge and make sure it's never beyond the redline. Keep it well below the red line and then you'll have a bit of leeway when you have emergency situations like taking off loaded heavily at the top of a mountain.

#4406100 - 02/19/18 12:15 PM Re: Huey catches fire nearly every flight now [Re: VF9_Longbow]  
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Originally Posted by VF9_Longbow
Ah I see what you mean - I think that's engines hot and running. A hot start is actually when fuel pools in the engine then catches fire and kills the engine.


Fair enough.
I just called it a "hot start" because that's the option I selected in the menu:
[Linked Image]

Originally Posted by VF9_Longbow
You just need to keep your eye on the EGT gauge and make sure it's never beyond the redline.

By the EGT gauge you mean the gauge labeled "EXHAUST" yeah?
[Linked Image]

As I mentioned before I find that gauge really hard to read in flight but I have been doing my best to keep it between the yellow bars (that is between 6 and about 7.75) as there doesn't seem to be a red line on mine:
[Linked Image]

However I still managed to crash and burn, or at least I crashed while my engine burned wink

Or are you talking about a different gauge?

#4406103 - 02/19/18 01:04 PM Re: Huey catches fire nearly every flight now [Re: S_Bartfast]  
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Mokkeri Offline
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Have you read the manual? This is from page 61.

The exhaust gas temperature indicator is located in the center area of the
instrument panel and is marked EXH TEMP. The indicator receives temperature
indications from the thermocouple probes mounted in the engine exhaust
diffuser section. The temperature indications are in degrees celsius. The system
is electrically self-generating.
The indicator is marked as follows:
 400°C to 610°С Continuous (green)
 610°С to 625°С 30 Minutes (red)
 625°С maximum 30 Minutes
 625°C to 675°С 10 Second Limit for Starting and Acceleration
 675°C to 760°C 5 Second Limit for Starting and Acceleration
 760°C Maximum gas temperature (red)

#4406134 - 02/19/18 04:23 PM Re: Huey catches fire nearly every flight now [Re: RhinoX55]  
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Mokkeri explained it well.

The yellow bars are not where you want the EGT (Exhaust gauge - you posted the correct gauge)

You need to keep that needle in the green! When you go beyond the first yellow bar, you're in the danger zone and you are harming your engine every second it is there. When you go over the second yellow bar (The redline, for practical purposes) your engine is being completely trashed and you are ensuring the necessity of replacement parts. Keep it above the red long enough and it catches fire and you die a fiery, crashy death.

Keep that needle in the green all the time by reducing collective and relying more on forward flight lift (ETL) rather than trying to force the aircraft into the air by brute force from collective and engine power. Your problems will disappear if you take this approach.

When you absolutely must go above the green zone, keep it as short as possible and I do mean short - a few seconds of hover while preparing to land is about all you can afford. On takeoff, orient your aircraft in a direction into the wind and heading downhill so you can reduce collective and thus stress on the engine as soon as possible.

Hope this helps keep your aircraft free of fires!

FWIW the DCS Huey actually does model Hot Starts (The engine destroying kind) and so you do actually need to look at the EGT gauge when starting up. If that puppy heads north of the yellow during your startup procedures, you'd better abort the start pronto. If it goes above yellow on the start and you try to continue the flight, you are going to have serious problems later on. Could be a fire or it could be a sudden engine failure somewhere later on in your flight. I suspect that if you have not been following correct start procedures up to this point, you've probably been hot-starting the engine unintentionally and it has probably contributed to your problems in flight. Keep it in the green and you buy yourself a bit of leeway if you need to abuse the engine later on.

Hot starts can be eliminated by only introducing fuel into the engine at the appropriate point in the start procedure - so either copy the autostart procedure or check the manual to make sure you're following the correct startup steps exactly. Fuel pumps and electric switches need to be in the proper places for this, as well as the correct throttle setting (Do not confuse with collective setting which only changes the pitch angle of the rotor blades)

#4474612 - 05/18/19 08:47 PM Re: Huey catches fire nearly every flight now [Re: RhinoX55]  
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irfanahmed1979 Offline
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Lahore, Pakistan
There's a good video about this by the Grim Reapers if anyone's interested.


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