Water coolers

[Bilbo_Baggins]

Just wanted to have a discussion about the water radiator damage. I was flying Hurricane tonight attacking Ju88 bombers and got hit in the water cooler, also perforated the cooler of one of the bombers. I found out that both he and I were able to fly around basically infinitely with a blown water cooler and coolant constantly streaming out for god knows how long.

 

It seems that blowing the water radiators have next to no effect on engine damage/overheating?  

Edited April 21, 2022 by Bilbo_Baggins

[Jade_Monkey]

Do we need to ask God how long that was? Was it 3 min? 15? 7 hours?

 

 

[I./JG52_Woutwocampe]

Hello @Bilbo_Baggins

 

I started a topic about leak issues a while ago in complaints

 

 

Feel free to add your input. And I clearly agree that most leaks have no effect until way too long.

 

[Supercharger]

2 hours ago, I./JG52_Woutwocampe said:

And I clearly agree that most leaks have no effect until way too long.

Your right, radiator damage seems to be graphics only. Another problem is that engines are dying without indication. The RPM's are fluctuating, but I never saw an oil pressure disagree..... 

[Yogiflight]

I depends. I ran out of water after a hit water radiator in the 110 after some minutes and the engine died because of overheating. The problem is, that the graphics have nothing to do with the damage. It is always the same picture you see, no matter how seriously the water radiators, oil radiators or fuel tanks are hit. Always the same picture, however you often have only small damage and another time, with the same picture, you run out of water, oil or fuel in a few minutes.

 

[I./JG52_Woutwocampe]

We should continue this conversation in the complaints topic so there are more chances the devs take notice and check it out. 

 

Or a mod needs to merge this topic with the other one.

[Jade_Monkey]

Yes, also please start adding data and supporting evidence.

Time measurements, attach tracks or screenshots when necessary.

 

Posting only about feelings is not very helpful for the devs even if there is an actual issue. They cannot thoroughly investigate every vague 2 sentence post that gets created while also delivering the planned work.

[Noisemaker]

I just shot down 2 JU-88s in SP with radiator hits (6x50cal).  The first took about 10 minutes to lose both engines and crash, the second about 20 minutes (one engine seized) before losing power on the second on finals (Was watching on third person as the flight back to Moscow from the front is long and boring at this point in the career).  So, they do kill, it just takes a while.

[oc2209]

4 hours ago, Yogiflight said:

I depends. I ran out of water after a hit water radiator in the 110 after some minutes and the engine died because of overheating. The problem is, that the graphics have nothing to do with the damage. It is always the same picture you see, no matter how seriously the water radiators, oil radiators or fuel tanks are hit. Always the same picture, however you often have only small damage and another time, with the same picture, you run out of water, oil or fuel in a few minutes.

 

I can't tell the difference between a water or a fuel leak's severity, but I can tell when an oil leak is heavy or not. The trail the plane leaves is noticeably thicker. A light oil leak will take 5-10 minutes to kill the engine, probably closer to 10, while a heavy leak will generally kill an engine in less than 5 minutes.

 

A heavy leak will also coat the windscreen (on a single engine plane) much faster than a light leak will.

 

2 hours ago, Noisemaker said:

I just shot down 2 JU-88s in SP with radiator hits (6x50cal).  The first took about 10 minutes to lose both engines and crash, the second about 20 minutes (one engine seized) before losing power on the second on finals (Was watching on third person as the flight back to Moscow from the front is long and boring at this point in the career).  So, they do kill, it just takes a while.

 

Are you positive they didn't have oil leaks hidden amidst the water leak trails? Light leaks, by the sound of it.

 

I've done just like you, and watched planes that I've damaged during a long career sortie. I've very, very rarely (I want to say never, but I can't confirm that) seen a pure coolant leak kill an engine before it can return to base and land. Depending on the map (say, Stalingrad) where bases are situated close to the frontline, it's likely that even an oil leak won't drop a plane before the AI successfully takes it home.

 

I've studied the oil leak behavior extensively, in career. When attempting to down a Sturmovik after your cannon ammo's depleted, it becomes imperative to put 7.9mm rounds into the oil cooler, and if you don't hit it hard, a light leak won't kill the engine reliably (quickly enough).

[I./JG52_Woutwocampe]

Another problem I have with coolant leaks is that an unpressurized system will have an almost immediate effect on the efficiency of the system. The engine should start to overheat way before it runs out of coolant especially if the engine is pushed hard.

 

But you can just go 2700 rpms, 1050 mm of hg with a Yak with a coolant leak and it wont overheat faster than it would normally until it dies 35 minutes after.

 

Not only do leaks take too long to kill the engine most of the time, you dont notice a significant decrease of performances in the meantime. 

[Dragon1-1]

The loss of pressure is proportional to the size of the hole in the system. It doesn't depressurize completely just because it's holed, the pressure is still there (and in fact, pushes the water out through the hole) as long as the pump works. If the hole isn't massive, it'll continue to run. Efficiency should decrease, since some pressure is lost to the hole, but it should depend on how big the damage is. Unless, of course, the pressure drops enough for the coolant to start boiling off inside the radiator. Then you might well not have a coolant system anymore. There are, however, cases when aircraft steamed for quite a while when trying to limp back to base. This was possible because the steam only formed at the hole.

Edited April 21, 2022 by Dragon1-1

[I./JG52_Woutwocampe]

12 minutes ago, Dragon1-1 said:

The loss of pressure is proportional to the size of the hole in the system. It doesn't depressurize completely just because it's holed, the pressure is still there (and in fact, pushes the water out through the hole) as long as the pump works. If the hole isn't massive, it'll continue to run. Efficiency should decrease, since some pressure is lost to the hole, but it should depend on how big the damage is. Unless, of course, the pressure drops enough for the coolant to start boiling off inside the radiator. Then you might well not have a coolant system anymore.

Yes, if the hole is really small then the decrease of efficiency/pressure will be slower since the leak is smaller but still it really shouldnt take 35 minutes until your engine dies all of a sudden without a gradual decrease of performances in the meantime.

 

Altitude should also be considered, as the boiling point decreases with pressure of course.

 

At 3000 meters, the effenciency drop should be more brutal than at sea level.

Edited April 21, 2022 by I./JG52_Woutwocampe

[Dragon1-1]

Pressure inside the system does not depend on altitude, so neither does the boiling point. The only thing altitude affects is the flow rate out of the hole, atmosphere basically provides some backpressure there. In general, water in such system is kept pressurized in excess of atmospheric pressure. Sudden loss of cooling is actually realistic - the system will keep operating more or less OK as long as there's no gas anywhere inside. The moment the pressure drops low enough, the water will boil, and it will do so across the entire system, killing its ability to take heat away from the engine. The engine will then proceed to cook almost instantly.

 

I recall a story about a either Typhoon or Tempest (or was it a Mustang?) that steamed for something like 45 minutes before ditching (IIRC, the pilot evaded capture, but I'm not sure). It was over France, in late WWII, but I don't remember where I read it. 

[I./JG52_Woutwocampe]

28 minutes ago, Dragon1-1 said:

Pressure inside the system does not depend on altitude, so neither does the boiling point. The only thing altitude affects is the flow rate out of the hole, atmosphere basically provides some backpressure there. In general, water in such system is kept pressurized in excess of atmospheric pressure. Sudden loss of cooling is actually realistic - the system will keep operating more or less OK as long as there's no gas anywhere inside. The moment the pressure drops low enough, the water will boil, and it will do so across the entire system, killing its ability to take heat away from the engine. The engine will then proceed to cook almost instantly.

 

I recall a story about a either Typhoon or Tempest (or was it a Mustang?) that steamed for something like 45 minutes before ditching (IIRC, the pilot evaded capture, but I'm not sure). It was over France, in late WWII, but I don't remember where I read it. 

 

Im pretty sure I remember reading about a german engine at the beggining of the war that had an unpressurized cooling system that lost efficiently at altitude even if it wasnt damaged because the boiling point is simply lower at altitude.

 

Anyway, if you say that a lower pressure at altitude increases the flow rate out of the hole, which is 100% correct, then, leaks at altitude should decrease the efficiency faster and the engine should die more quickly.

 

Also I'm sure there are cases of planes leaking coolant for a while and still take you back home after a long ride but it should be the exception, not the rule. In IL2 its the other way around. 

 

Liquid cooled engine were notoriously known to be easier to put down than air cooled engines. That might have something to do with the shape of the engine and that the inline engine was more compact as opposed to a radial air cooled engine that was more 'open' to let the air flow, but most of weakness to damage of the inline liquid cooled engine was....its delicate cooling system. 

 

In IL2 GB, I really dont see that weakness coming through for the inline engines. In fact, I'll tell you what, the Merlin and Klimov V12's are actually even harder to take down than the M-82, the BMW801 and the Double Wasp!

Edited April 21, 2022 by I./JG52_Woutwocampe

[Noisemaker]

3 hours ago, oc2209 said:

Are you positive they didn't have oil leaks hidden amidst the water leak trails? Light leaks, by the sound of it.

Yes, pretty positive.  They were leaking white (Coolant) and green (Fuel), but not black (Oil).

OT:  I'd like actually, to take a moment here and thank the mission designers for the improvements to the SP campaign missions.  We were a 3 flight of P40s against 9 JU88s and 6 109s, and we managed to repel the attack (All bombers dropped their bombs before target), and all 3 P40s made it home (We suffered two pilots wounded, including myself from one of the JU88 attacks, but no aircraft lost), as the 109 escorts stayed with their bombers and withdrew, instead of chasing us back to base.

[oc2209]

Quick example of a heavy oil leak versus a light one, and how long it takes a 109's engine to seize on Stalingrad's summer map, and both radiators hit.

 

First, the heavy oil leak:

 

Spoiler

 

 

The light oil leak + radiator leaks:

 

Spoiler

 

 

I began recording in both cases after I'd made the firing pass that caused the final leak. So there might be a 30-60 second gap between when I started the first leak and the last, but it's not really worth talking about.

 

In the summer recording, I led the 109 on a merry chase back and forth across the map. It had to maintain combat power to stay close to me. I was doing about 299 MPH on average, and it never got close enough to fire at me. Unsure if that was from the oil leak or the coolant leaks.

[oc2209]

For frame of reference, here's a pure oil leak in a Sturmovik, caused by nothing but 15mm hits:

 

Spoiler

 

 

Another one where I just fired my 7.9mm, the engine seized in about 8-9 minutes.

 

For those keeping track: the Hurricane (w/12x.303) caused a 109's engine seizure in about 3 minutes; the Yak's 7.6mm caused a 109's seizure on a summer map in almost 20 minutes (obviously many fewer hits than the Hurricane example); while the Sturmovik seized in as little as ~5 minutes from 15mm strikes.

 

I think for another test I'll try to hit the Spitfire V's radiator with no collateral damage.

[oc2209]

Wow this test is a pain the ass.

 

The problem with hitting a specific part of a plane with zero collateral damage, is that you must be significantly more maneuverable than said target plane. Being maneuverable enough to get a kill is totally different.

 

Anyway, long boring story short, I did manage to hit a Spit V in just the radiator, but I nicked the pilot too, so the test was ruined. He spent 90% of the recording in a gentle climbing turn, passed out, before his engine burned up after about 6 minutes. Can't tell if it burned up from the radiator leak or from leaving it on too high of throttle.

 

This is the only clean, perfect coolant leak I got:

 

Spoiler

 

 

I only fired the Spit's .50s. DVD markers indicate only about 5 hits total, with 2 of those right near the radiator. So it was either holed once or twice. The other hits I got were in the tail and one in the wing, nowhere near anything that leaks coolant.

 

Once again, I began recording within seconds of causing the leak. So, 20 minutes from start to engine failure in Stalingrad summer map.

 

After approximately 4 minutes (when this recording begins), the P-51 AI breaks off pursuit. Despite the fact that I'm only going about 300 MPH when he disengages. So there's clearly some performance impact on him.

 

The AI then spends the rest of the time circling until his engine dies. Funny that it doesn't outright seize though. Maybe the AI is throttling back to avoid overheating, and eventually throttles back so far that he spins out and crashes.

 

Anyway, I'm not doing this test again.

[Yogiflight]

8 hours ago, I./JG52_Woutwocampe said:

because the boiling point is simply lower at altitude.

you can see this pretty good, for example, in the 110s, which show different maximum water temperaures for different altitudes at the water temperature gauge. Unfortunately, this is not modelled in game. You have more or less the same water temperatures at all altitudes without different effects on cooling.

 

8 hours ago, I./JG52_Woutwocampe said:

That might have something to do with the shape of the engine and that the inline engine was more compact as opposed to a radial air cooled engine that was more 'open' to let the air flow,

Not to forget, that inline engines were not in the air flow. There was no air inlet for engine cooling for aerodynamic reasons.

[RyanR]

We're probably overthinking this. The developers have mentioned that the damage model will see some work.

 

As for how long will an engine go, 25-30 years ago, I got through 2/3 of a summer in my early 20's, commuting 45-60 minutes in my first car (A K-Car derivative... with a turbo, even). This car was slurping coolant somewhere in the works (head gasket, most likely). So, I went 40-60 minutes twice a day with a car that consumed 25-50% of it's coolant each way. I carried gallons of pre-mixed with me.

 

I'd say we're doing OK in-game. I have burned up a few single engine fighters due to lost coolant or oil. I've also brought 110's and P-38's back with a feathered engine due to lost coolant. 

 

As for me, fortunately that car died one morning in a fantastic cloud of steam.

 

-Ryan

[FeuerFliegen]

On 4/22/2022 at 2:56 AM, Yogiflight said:

 Unfortunately, this is not modelled in game. You have more or less the same water temperatures at all altitudes without different effects on cooling.

 

Actually I believe it is modeled in game;  one time a couple years ago I was flying at 9km altitude in a 110 E-2 and the engine would overheat at what would normally be a very low coolant temperature; something like 80 C if I remember correctly.  

 

Edit: just tested it now at 10km in summer Stalingrad map; I got the overheat warning at 78-79C coolant temperatures.  At 8km, I would start overheating at 84-85C.  7km, 89C.  6km, 92C.  5km, 96-97C.  4km, 100C

 

 

As far as the main topic of this thread, engines dying due to loss of coolant- it seems like the one plane I've had to worry about it most is in the Bf 110 E-2; where as other planes you seem to have an unrealistic amount of time to fly with a coolant leak.

Edited May 2, 2022 by SCG_FeuerFliegen

[Yogiflight]

34 minutes ago, SCG_FeuerFliegen said:

Actually I believe it is modeled in game;  one time a couple years ago I was flying at 9km altitude in a 110 E-2 and the engine would overheat at what would normally be a very low coolant temperature; something like 80 C if I remember correctly.  

 

Edit: just tested it now at 10km in summer Stalingrad map; I got the overheat warning at 78-79C coolant temperatures.  At 8km, I would start overheating at 84-85C.  7km, 89C.  6km, 92C.  5km, 96-97C.  4km, 100C

Interesting. I will have to try it myself. The reason, why I thought it is not modelled is, I was flying quite some fighter missions at 5km+ in PWCG and from what I remember the temperatures were definitely higher than they should be, according to the gauge. I have to admit I never tried it in altitudes you were flying, simply because the engines of the E2 are too low powered to reach the 350km/h IAS ( in fact I set 360, because the cruising speed is always 10km/h slower than what you set and the map tells) in that altitude, I set in PWCG as the E2's cruising speed.

 

41 minutes ago, SCG_FeuerFliegen said:

As far as the main topic of this thread, engines dying due to loss of coolant- it seems like the one plane I've had to worry about it most is in the Bf 110 E-2; where as other planes you seem to have an

I rarely have coolant losses, usually it is fuel leaks, but from what I remember you are right, you can't fly too long with a coolant leak.

[Yogiflight]

10 hours ago, SCG_FeuerFliegen said:

Edit: just tested it now at 10km in summer Stalingrad map; I got the overheat warning at 78-79C coolant temperatures.  At 8km, I would start overheating at 84-85C.  7km, 89C.  6km, 92C.  5km, 96-97C.  4km, 100C

I just did a short test in 5km and 9km and can confirm that. The reason, why I didn't get overheating in 5km, when flying fighter missions in PWCG is, I always tried not to get over the duration maximum temperature of 94°C, while cruising. The fights always were at lower altitudes.

What is quite disappointing is, that the markings on the gauges don't fit to the engines we have in game as they surely are for the DB 601 P engines not the DB 601 A, we have in game.

[jollyjack]

You can also just take a break ..