Engine damage modelling......HTC?

[eddiek]

Well, when I originally posted the other thread, "Thoughts on the game" I incorrectly assumed guys would check it out.

So, here it is, correctly titled this time.  Enjoy.
I've visited with a couple WW2 veterans now who both said the same thing about when your engine(s) were damaged.
Rarely, if ever, did they continue to put out full power. As it is now in AH, you get one of 4 things:
A: No engine damage. 'Nuff said

B: Engine oil hit. Okay your oiling system is hit in some way. As your oil pressure falls, those engine parts are going to start heating up. You have a finite amount of time left to get your bird on the ground.

C: Engine coolant. Pretty much the same as above. I have found that if I extend and I have enough altitude, I can stretch it out by shutting down the engine and letting the coolant temps drop while I attempt to glide to a friendly base. Starting the engine for 5 or 6 seconds sends the temps right back up, but I can extend far enough usually to set down at a friendly base if I watch the temperature.

D: Engine hit. The engine is dead. Again, nothing more said, self explanatory.

What I propose is this: Any engine damage should cause an immediate loss of full engine power. Maybe you lose a percentage of your MAP, or the engine RPM falls. Regardless, you are not gonna get full power from the powerplant.
Maybe add this as a nonspecific damage item that you can see when you hit CNTRL+D.
What I see this doing is reducing the # of planes you see zooming around in the arenas, trailing smoke or coolant, still getting full power and zooming up and down and around. To me, it would add another element of realism to the game. Other than the German ace Knocke, I have not heard of ANY pilot sustaining engine damage to his plane and continuing the fight. It just was not possible. The crate was in trouble and their mindset was getting the thing out of the fighting and trying to land her. They could not engage in anything other than defensive moves anymore, as the engine would not allow them to do the things they would normally do if the engine were whole.
I think this would help the game. The one who only want to go out and furrball still get to, but now they have to watch what they are doing more closely, cause if they get hit in the engine, they are not gonna be able to keep chasing or TnB. The ones who plan their fights, set them up and then execute them will get the satisfaction of seeing the plane at a very minimum slow down and become less of a threat when they do score hits. Nothing more frustrating than carrying out an attack, getting hits on the other plane, he trails smoke or coolant, yet can still run around til the engine seizes from lack of vital fluids. And, BTW, getting 4 or 5 kills because he still has full power available to him.
Just my thoughts on this..........

[RabidSquirrel]

Eddiek,

     Hello mate,I was just looking around here when I saw ur post. I agree with you 100% on what you had to say. Alot of pilot's get kill's even though their engine has been hit in some shape or form. Myself has alway's said if it's going to be a flight sim it better be as real to life as possible. I have found alot of thing's that need's to be included in AH but the odd's of them happening are very slim to none. I hate being shot down by someone who has a messed up engine and are roaring the skie's with full power. There's no way any plane could take a hit to the coolant,oil or any other vital part of the engine and still fly with max power. HTC need's to add engine damage feature's to make this more realistic for those whole like the realism. For example: Say your getting ready to take of to intercept some enemy fighter's that are 50 mile's away from your base. Your set on the runway and you fire up your crate,you proceed to push the throttle forward to fast and the engine break's down right on the spot. This would be known as torque effect. This add's realism and make's the game more enjoyable. Also it make's you take more care of your engine. I have played a couple other flight sim's and damage taken by the engine lead's to engine failure. A good example of this would be Combat Flight Simulator. I have broken my engine many time's on take-off's. HTC please do something about this. More realism equal's more fun!!

Squirral

[popeye]

I don't see why an engine would lose power just because it had an oil or coolant leak.   I agree that nasty things would happen when the engine overheated, but I don't think there would be an immediate effect from a leak.  I had a Toyota that leaked oil all the time, and it ran fine.  

[eddiek]

 popeye.......I've had a few of those type cars myself.

What I am talking about is damage from combat.  A leak, be it coolant or oil, resulting from cannon shells or machine gun bullets is not gonna be the same as a slow seep from an old radiator hose.
We're talking about those shells ripping through the cowling, tearing up wires, fuel lines, etc, causing the engine to lose power......not all of it, as I have read too many stories of pilots who got their sick birds home after the engine took hits......but they sure didn't do it at full power and full speed either.     We're talking about some sick birds, ones that couldn't always make it to cruise speed, much less run wide open, top speed, balls to the wall......no worrying about the engine.
Your bird's engine gets damaged, and it's time to start looking for a way out of the action, or bail.
Just something I think would help the "realism" or "authenticity" in the game.  

[Seeker]

You don't have to have an oil leak to have oil probs....

I've blown up two 3l Ford Capri's due to poor sump baffeling.

Pull to many G's in a bend (strange to think of it like that, but that's what happens); and the oil is thrown  to the outside of the curve, away from the pump pick up, hey presto ! instant oil starvation at full throttle........


I've read references to Hurri 1's suffering from this; I wonder how common it was?

[Don]

>>>I've read references to Hurri 1's suffering from this; I wonder how common it was?<<<<

F4Us and F6Fs were to have had similar problems, particularly when inverted for any period of time; doesn't happen in AH.
Overrev isn't modeled either to my knowledge. I wonder how that would go over if it were.

[lemur]

Rehashing my comments from the other thread:

A coolant leak simply means the engine can't shed heat as effectively (the system relies on pressure to work well.) Basically the max temp the cooling system can handle drops by about 10 degrees C.

An oil leak just means the engine is running out of oil.

The really bad stuff happens when the engine runs LOW on oil and coolant.

Without enough coolant the engine can't shed heat properly and it's temperature skyrockets quickly.

Without enough oil the engine generates more heat at any given RPM and quickly overloads the ability of the cooling system to shed that heat. But just remember: most aviation engines have way more oil than coolant and they really don't heat up until they are down to less than 1/3 their oil capacity.

In game terms:

The ability of the engine to shed heat should be modeled as:

Heatloss = (Airspeed + constant ) * (EngineTemp - AmbientTemp) * (Coolant %) / (Cooling system damage)

You'll note Air-cooled motors are always at 100% coolant-wise (hence the durability of the p-47 engine to damage)

And the engine heat generated should be modeled as:

Heatgain = (Manifold Pressure) / (Oil % + constant)

As the amount of oil left drops to 0 the heat gain approaches infinity.

Just do Heatgain-Heatloss to determine the change in engine temp.

Now what to do when an engine gets too hot?

At a certain temp, the coolant boils and becomes ineffective. So the ability to shed heat goes down even more.

At a higher temp, the oil loses effectiveness and the engine takes damage. As the engine takes damage it's max power output drops, pistons start scuffing cylinder walls, bearings fail, con-rods break.

In game terms:

if temp exceeds max allowed coolant temp, cooling system efficiency drops by 50% until either all coolant is gone (a long time to boil it all off) or temp drops back under this amount.
Model this as a coolant leak and cooling system damage as long as temp > whatever. When temp drops damage is 'healed'

if temp exceeds max allowed oil temp, engine begins to take damage. The higher the RPM & temp the faster this damage occurs.

In game terms model this first as reduced power output, then greatly reduced power output (and black smoke & clanking) and finally engine seizes solid.

So overheating a water-cooled engine first results in lots of white smoke and a greatly reduced cooling ability until the oil overheats and then damage occurs. Simply gliding for a bit at idle would cure it.

Damage the cooling system? Ouch. The plane gradually looses the ability to get rid of heat, the oil cooks, the motor siezes.

Damage the oil system? The plane gradually produces more and more heat, the oil cooks yadda yadda.

As you can see, one big advantage of an air cooled engine is that
a) There's no cooling system to damage.
b) No matter how hot the engine gets, it'll still shed heat.

Putting a bullet through a water cooled engine:
(water jackets everywhere in most engines) Model that as engine damage and a coolant leak & oil leak. Result: The engine's output is reduced and the oil level begins to drop. And the ability to get rid of that heat begins to drop. After a short while the engine temp skyrockets, the oil cooks, the engine takes more damage.


Putting a bullet through an air-cooled engine:
Model that as engine damage and an oil leak. Result: The engine's output is reduced and the oil level begins to drop. After a while the engine temp starts to climb, but the pilot can manage the heat created by lowering his RPM.


Plenty of stories of p-47 pilots getting a cylinder shot off but the engine would continue to limp along until it got really low on oil.


My slightly more than dos pesos.

~Lemur

[eddiek]

Best response so far, lemur......maybe I should have included the likelihood of nicked or severed electrical leads, spark plugs wires, mags, etc........not just coolant and oil?

Trying to remember the formula here.........an engine's output is reduced when the engine temp exceeds certain temps, due to decreased density of the intake charge, preignition/detonation, etc?
Help me out someone, I can't remember the exact numbers.

Okay, not really trying to compare the two, but I found this last night.

I checked out IL-2 last night, the demo at least, and they have something near what I am talking bout.
The engine overheat message popped up, and I left it at near 100% throttle for a while just to see what it did.
The higher the temp climbed, the less power and speed my 109 had.  Make sense?  Had I tried reducing the throttle a bit, temps would have fallen back to safe levels and max power could have been achieved, but I didn't so the power gradually fell off til I was barely at flying speed, then the engine seized.  This was with NO damage from bullets, shells, etc, but the same idea applied.

FWIW, the comparison of radials and inline or V-type engines is another thing I was trying to consider.  The most durable engines were almost always the radials, when compared in terms of ability to sustain damage and stay together at least.

[AmRaaM]

Especially like the many times when u get shot in the bellybutton and the eng gets hit, bullet musta went up the exhuast and damaged the rings, and like it when the .303 start hittin your bellybutton and your pilot gets wounded 91.4% of the time.

[Tilt]

Originally posted by Don
[BOverrev isn't modeled either to my knowledge. I wonder how that would go over if it were. [/B]

First I think you need to define what is actaully meant by overrev.... a debate that was never resolved elsewhere....


Tilt

[Ripsnort]

Speaking of engine damage modeling, can anyone tell me why a fragile engine such as the 262 has, runs for so long after its been damaged in AH? That sucker should shut down after about 30 sec.  Last I remember, I went about 5 min. with a damaged 262 engine on one side before it finally died.

[lemur]

Originally posted by AmRaaM
Especially like the many times when u get shot in the bellybutton and the eng gets hit, bullet musta went up the exhuast and damaged the rings, and like it when the .303 start hittin your bellybutton and your pilot gets wounded 91.4% of the time.

Simple: The bullets don't come straight out from your guns, they come out from the wings. If you hit a plane at your convergence distance the bullets are, in fact, coming in from the sides.

~Lemur

[lemur]

Originally posted by eddiek
Best response so far, lemur......maybe I should have included the likelihood of nicked or severed electrical leads, spark plugs wires, mags, etc........not just coolant and oil?

But in game terms, that just means reduced engine output. Might as well simplify it and say x amount of damage = x amount of power loss and leave it at that. I honestly don't care if that 50 cal bullet hit a cylinder or took out a magneto. The end result is "my engine don't work so good no more"

And yeah, a hot engine doesn't produce as much power as a cold one. But it's nothing compared to the power loss from shot rings or a thrown rod.


~Lemur

[eddiek]

Lemur, so you're for adding this to the game?  
I hope so, nothing you've said points in the other direction......

[lemur]

Want it? WANT IT!

Uh, yeah. It'd be cool, and a lot better than what we have now.

~Lemur