Mi-24 Random Engine Fire - need help investigating

[Cr33p3r]

Last night on MP server (Liberation), I'm in Syria and its cold (got some icing warnings) and I'm 280KPH at 400m height trucking on out to the front lines. I've gone about 48nm and then I start to get some icing warnings on the panel (red light). So, I make sure pitot heat is on.  I keep going. I have the bird trimmed nicely so I'm basically hand's off and not gaining or losing altitude. No enemies around and nobody is shooting at me as Tacview shows afterwards. I get an engine fire and start to lose power and then it grows and I burn up. Has anyone else had just a random fire cause their demise like this? I had no other warnings.

Any idea on what may have caused this?

Here is a video but I didn't hit record until after the problems started. Any input appreciated. I may have missed some important step/switch to keep this from happening.

https://youtu.be/_xmzXGvpz3c

Thanks!

 

[Deimos]

Same here. I´m flying the Hind since 1500hrs and same happened twice to me on caucasus map at warm sunny weather. no enemy around, just flying straight.

I try to consider it more as an oddity than as a problem.

[randomTOTEN]

You probably over stressed your engines. Unfortunately your video is useless, because at the beginning the main rotor is already below generator cutoff speed, and most relevant engine gauges have lost electrical power.

[Cr33p3r]

Ahh. good to keep in mind. I was pushing things due to impatience. I'll run some more tests. I was also heavy and that may have contributed to the stress. pretty cool this is modeled in DCS.

[AeriaGloria]

1 hour ago, Cr33p3r said:

Ahh. good to keep in mind. I was pushing things due to impatience. I'll run some more tests. I was also heavy and that may have contributed to the stress. pretty cool this is modeled in DCS.

Pitot heat is not anti ice. 
 

  I don’t know what Toten is talking about, but it is IMPOSSIBLE to overstress the Mi-24 engines, Mi-8, or Ka-50. The engine governor will automatically cut fuel flow at max temperature. The manual says to only have the engine at take off power for 5 minutes to reduce maintenance over the life of the engine. PilotMi-8 former head of Belsimtek who made this module and is former Army pilot of Mi-8 said you could run engine at full power for consecutive flights and not notice anything until many flights later. 
 

  What happened to you sounds like icing. You said you turned on pitot heat but when you get the “ICING” warning you need to turn on “Anti-Ice” by the generator panel by your right elbow. You need turn on anti ice from auto to manual; then flip engine/dust protection anti ice from off to on for both left and right engine. All three switches need to be up for anti icing to work. It’s a good idea to turn on pitot heat at the same time.
 

   Another person said they got engine problems at caucuses. If you go high the temperature decreases. You don’t have to get that high on a usually colder map like Caucuses to experience 0 degrees Celsius and icing. 
 

   Be aware that anti icing will cause about a 20% decrease In power. If you need to hover with anti icing your hover weight needs to be 900 kg lower then without anti ice. 
 

Credit for photo is chucks guide, which I heartily recommend 

 

Edited November 17, 2022 by AeriaGloria

[Northstar98]

Another thing to check is the birds setting, it's very unlikely but you will get birdstrikes that way (there isn't a physical bird you can fly into), but it can lead to random fires.

[Cr33p3r]

This is great info and most likely the cause of my issues. I will know what to do when that icing light comes on now.

[DeMonteur]

On 11/17/2022 at 8:06 PM, AeriaGloria said:

Pitot heat is not anti ice. 
 

  I don’t know what Toten is talking about, but it is IMPOSSIBLE to overstress the Mi-24 engines, Mi-8, or Ka-50. The engine governor will automatically cut fuel flow at max temperature. The manual says to only have the engine at take off power for 5 minutes to reduce maintenance over the life of the engine. PilotMi-8 former head of Belsimtek who made this module and is former Army pilot of Mi-8 said you could run engine at full power for consecutive flights and not notice anything until many flights later. 
 

  What happened to you sounds like icing. You said you turned on pitot heat but when you get the “ICING” warning you need to turn on “Anti-Ice” by the generator panel by your right elbow. You need turn on anti ice from auto to manual; then flip engine/dust protection anti ice from off to on for both left and right engine. All three switches need to be up for anti icing to work. It’s a good idea to turn on pitot heat at the same time.
 

   Another person said they got engine problems at caucuses. If you go high the temperature decreases. You don’t have to get that high on a usually colder map like Caucuses to experience 0 degrees Celsius and icing. 
 

   Be aware that anti icing will cause about a 20% decrease In power. If you need to hover with anti icing your hover weight needs to be 900 kg lower then without anti ice. 
 

Credit for photo is chucks guide, which I heartily recommend 

 

 

Yesterday I encoutered similar scenario but without Icing. During NOE approach to farp, speed about 120km/h I noticed natasha Say something about left engine. Look on Fire panel no fire or extinguished bottle there. So I doesent care. After a minute I get fire warning and heard bang of extinguisher bottle without any shooting at me. 

[Longiron]

Had this happen today also, was about 900m at takeoff 760mb and 15c clear sky 

I was heavy at 28000 

Made IGE hover check and was in max continuous bracket on engine pressure gauge. 

Got to 250kph with a 10kn headwind and setup for cruise, then get warning, fire left engine. Fire bottle discharged on the left engine and TIT peaked on left engine like fire bottle did nothing. 

So i Jett my stores, reduce power and pitch for 150kph looking for something flat to roll land on. Then the oddest thing, left engine stabilize and both are now about 980c TIT. So now I'm like ok, I'm less then 2 min from the FARP I took off from so I turn downwind and make for home, thinking I got good power.

Now I'm low on speed after the 180 turn so I pull some power and I'm not getting much so I set emergency power and things get better, I'm climbing and speeding up. 

...fade to black... and I'm a fireball soon to be a stain on some field.

 

Was very odd, considering I had a normal flight earlier on the session. 

 

[Miro]

1. Bird settings enabled

2. Random system failures enabled

This type of failure has nothing to do with icing.

[WildBillKelsoe]

I think you could have double tapped the engine condition lever to emergency and forgot to return it midway.. RCtrl+Home twice...

[AeriaGloria]

5 hours ago, WildBillKelsoe said:

I think you could have double tapped the engine condition lever to emergency and forgot to return it midway.. RCtrl+Home twice...

That shouldn’t affect anything. 

The engine governor looks at a combination of collective postion, throttle twist grip, and ECL to decide how hard to run the engines. For example, you could have ECLs at anywhere from 70-100% and still have full power. Full power might not decrease until say 69%. I don’t know if it’s actually 70%, but they don’t do anything different then being like a separate throttle twist grip for each engine. 

I have the actual figures somewhere, but basically, all the ECLs will do when turned up is command 100% engine power, no different than when throttle twist grip is raised. Moving the ECLs up will not trigger an emergency mode or any additional power failure (unless your throttle/collective is down). 

In fact, it seems the emergency power functions of the TV3-117VMA isn’t modeled in this module, so there is no way to trigger the 2400 HP regime that I know of. From everytying I’ve read in Mi-24 manuals, the process should be entirely automatic and invisible to the pilot. 
 

The only way to ruin pretty new engines in a real Mi-24 that work perfectly would be if someone in the cargo cabin turned off the governor and the pilot pushed the engines hard after that. But the governor panel in the cargo cabin isn’t modeled either in Mi-24P in DCS. There is also a SPU-8 intercom and a ASO-2V dispense button back there

[WildBillKelsoe]

15 hours ago, AeriaGloria said:

That shouldn’t affect anything. 

The engine governor looks at a combination of collective postion, throttle twist grip, and ECL to decide how hard to run the engines. For example, you could have ECLs at anywhere from 70-100% and still have full power. Full power might not decrease until say 69%. I don’t know if it’s actually 70%, but they don’t do anything different then being like a separate throttle twist grip for each engine. 

I have the actual figures somewhere, but basically, all the ECLs will do when turned up is command 100% engine power, no different than when throttle twist grip is raised. Moving the ECLs up will not trigger an emergency mode or any additional power failure (unless your throttle/collective is down). 

In fact, it seems the emergency power functions of the TV3-117VMA isn’t modeled in this module, so there is no way to trigger the 2400 HP regime that I know of. From everytying I’ve read in Mi-24 manuals, the process should be entirely automatic and invisible to the pilot. 
 

The only way to ruin pretty new engines in a real Mi-24 that work perfectly would be if someone in the cargo cabin turned off the governor and the pilot pushed the engines hard after that. But the governor panel in the cargo cabin isn’t modeled either in Mi-24P in DCS. There is also a SPU-8 intercom and a ASO-2V dispense button back there

It is very difficult considering the cargo cabin governor is practically in the forward half so unless the cargo is an elephant with its trunk touching the governor switches, I hardly see a connection. That said, I think the OP might have overstressed the engine one way or the other either by ECL misuse or commanding sudden RPM or it might be their controller hardware wiring commanding a 0-100 due to poor soldering or power spike/surge. Lots of culprits to point to a single cause on this one.

[AeriaGloria]

1 hour ago, WildBillKelsoe said:

It is very difficult considering the cargo cabin governor is practically in the forward half so unless the cargo is an elephant with its trunk touching the governor switches, I hardly see a connection. That said, I think the OP might have overstressed the engine one way or the other either by ECL misuse or commanding sudden RPM or it might be their controller hardware wiring commanding a 0-100 due to poor soldering or power spike/surge. Lots of culprits to point to a single cause on this one.

But there is no way to damage the engine in DCS Mi-24P without icing or birds or other ME failures. You can’t damage it by moving the ECLs or giving “too much” power. 
 

I found the approximate numbers. There is a regulator pump that decides how hard the engine is run. 
 

It looks for a combination of 120mm of movement to correlate to 100% power. It will not go over it. 

Throttle twist can +/- 50mm. 
Collective can do +/-70mm. 
Each ECL does +/-70 for its individual engine. 
 

And yea, 50+70+70 is more than 120. So basically, If you already have twist grip at max, 50mm, and collective fully up, +70, you get 120. The ECL lever shouldn’t increase engine power at all when moved above half of collective is up. You can see this easily in game also by having ECL up/auto, collective up, and try to reduce engine speed with throttle twist. You will notice the engine will stay the same speed for a long time until you turn down the twist grip quote a bit. The ECLs do the same. There is no scenario in regular flight where having the throttle twist set to max, and collective up, and then moving ECL from auto to max should change anything. Auto will automatically give you max engine power as long as twist grip and collective is up. 
 

I don’t know what else to say but if you try in DCS, In above freezing temperatures, with birds off, you will not have engine failure or degradation by running the engines hard, moving ECLs, or anything else. 

Here is a picture of the regulator pump, as long as it sees enough travel from ECL+twist grip+ collective, then moving ECLs up should do nothing. 
 

This feature was used in Afghanistan. Pilots would turn down throttle twist grip/ECLs to get extra rotor pitch without throttle, then add in correction during take off run. This was to help reduce dust on takeoff

 

Yes it’s complicated and hard to understand, but the point is the Mi-24 is very smart and well built, and will not allow you to abuse the engine unless you have a crew chief in the cargo cabin flipping switches that don’t exist in DCS. 

Edited April 20, 2023 by AeriaGloria

[admiki]

1 hour ago, WildBillKelsoe said:

It is very difficult considering the cargo cabin governor is practically in the forward half so unless the cargo is an elephant with its trunk touching the governor switches, I hardly see a connection. That said, I think the OP might have overstressed the engine one way or the other either by ECL misuse or commanding sudden RPM or it might be their controller hardware wiring commanding a 0-100 due to poor soldering or power spike/surge. Lots of culprits to point to a single cause on this one.

You quite literally can not overstress engines in Mi-8/24. In 24 you can't even droop your rotor.

Once I flew Mi-24 at full collective (and I mean full) for 45 minutes and finally got bored, so I just quit. I even flew Mi-8 with drooped rotor due to how much collective I had for 15 minutes or so and again got bored and quit.

It seems I quit a lot?

[WildBillKelsoe]

19 hours ago, AeriaGloria said:

But there is no way to damage the engine in DCS Mi-24P without icing or birds or other ME failures. You can’t damage it by moving the ECLs or giving “too much” power. 
 

I found the approximate numbers. There is a regulator pump that decides how hard the engine is run. 
 

It looks for a combination of 120mm of movement to correlate to 100% power. It will not go over it. 

Throttle twist can +/- 50mm. 
Collective can do +/-70mm. 
Each ECL does +/-70 for its individual engine. 
 

And yea, 50+70+70 is more than 120. So basically, If you already have twist grip at max, 50mm, and collective fully up, +70, you get 120. The ECL lever shouldn’t increase engine power at all when moved above half of collective is up. You can see this easily in game also by having ECL up/auto, collective up, and try to reduce engine speed with throttle twist. You will notice the engine will stay the same speed for a long time until you turn down the twist grip quote a bit. The ECLs do the same. There is no scenario in regular flight where having the throttle twist set to max, and collective up, and then moving ECL from auto to max should change anything. Auto will automatically give you max engine power as long as twist grip and collective is up. 
 

I don’t know what else to say but if you try in DCS, In above freezing temperatures, with birds off, you will not have engine failure or degradation by running the engines hard, moving ECLs, or anything else. 

Here is a picture of the regulator pump, as long as it sees enough travel from ECL+twist grip+ collective, then moving ECLs up should do nothing. 
 

This feature was used in Afghanistan. Pilots would turn down throttle twist grip/ECLs to get extra rotor pitch without throttle, then add in correction during take off run. This was to help reduce dust on takeoff

 

Yes it’s complicated and hard to understand, but the point is the Mi-24 is very smart and well built, and will not allow you to abuse the engine unless you have a crew chief in the cargo cabin flipping switches that don’t exist in DCS. 

 

true but its possible the aircraft sustained damage from birdstrike or random failure. I just checked above our discussion and it looks OP has random failures and birds checked.

19 hours ago, admiki said:

You quite literally can not overstress engines in Mi-8/24. In 24 you can't even droop your rotor.

Once I flew Mi-24 at full collective (and I mean full) for 45 minutes and finally got bored, so I just quit. I even flew Mi-8 with drooped rotor due to how much collective I had for 15 minutes or so and again got bored and quit.

It seems I quit a lot?

its a game anyways... 

[randomTOTEN]

I just tried my very hardest to burn the engines out on my test mission. 15 minutes of the highest power I could possibly demand. Didn't do anything, the Hind had zero issues with it. Tried at both 28C and 4C.

2 hours ago, WildBillKelsoe said:

its a game anyways... 

I don't understand what the point of this remark is supposed to be...

Edited April 21, 2023 by randomTOTEN

[AeriaGloria]

3 hours ago, WildBillKelsoe said:

true but its possible the aircraft sustained damage from birdstrike or random failure. I just checked above our discussion and it looks OP has random failures and birds checked.

its a game anyways... 

I wonder how big a bird can fit in the gaps through the dust protector

[WildBillKelsoe]

13 hours ago, randomTOTEN said:

I just tried my very hardest to burn the engines out on my test mission. 15 minutes of the highest power I could possibly demand. Didn't do anything, the Hind had zero issues with it. Tried at both 28C and 4C.

I don't understand what the point of this remark is supposed to be...

 

its a game? I think its very obvious....

 

12 hours ago, AeriaGloria said:

I wonder how big a bird can fit in the gaps through the dust protector

raptor

[DeMonteur]

I can confirm this failure IS random. I have empty mission only with Mi-24 and truck. Payload: Full fuel, S-8OFP2 on outer pylons. I am flying way below max power, no icing. I have no birds and no random failures checked.

It is a bug... 

Edited May 1, 2023 by DeMonteur

[randomTOTEN]

3 hours ago, DeMonteur said:

I can confirm this failure IS random.

Do you have random failures enabled?

[DeMonteur]

1 hour ago, randomTOTEN said:

Do you have random failures enabled?

As you can read in previous post no. I do not have random failures enabled. In other words. I have random failures disabled. As well as birds set to 0.

Edited May 1, 2023 by DeMonteur
Write it more clearly

[AeriaGloria]

5 hours ago, DeMonteur said:

I can confirm this failure IS random. I have empty mission only with Mi-24 and truck. Payload: Full fuel, S-8OFP2 on outer pylons. I am flying way below max power, no icing. I have no birds and no random failures checked.

It is a bug... 

 

Then you should record a track and make a post in the Bugs and Problems section

[DeMonteur]

23 minutes ago, AeriaGloria said:

Then you should record a track and make a post in the Bugs and Problems section

Ok hoped it is already known bug and it is reported. Will do

[DeMonteur]

11 minutes ago, DeMonteur said:

Ok hoped it is already known bug and it is reported. Will do