IL-2 BoS - Managing damaged engines
 

In real life a damaged engine would be run with lowered power and rpm settings and max cooling to reduce the stresses on it and keep it running.

There are a variety of opinions on this in the IL-2 BoS community. My view is that if you reduce the power and rpm you naturally reduce your speed. This means that if you reduce your speed to 200 from 400 it will take you twice as long to get to your destination. It also means you will be running the damaged engine for twice as long increasing the chances of a fail.

Personally, I run engines and rpm at 90% pwr and rpm because it "feels" right. But there is no way to tell and confirm if what we are doing actually works!

When we get a flag saying "First engine is damaged" we have no idea by how much. Thus we have no idea if increasing or decreasing the power, rpm, or cooling rads has any effect whatsoever on keeping the engine running.

The assumption is that the game mechanics/physics will mimic real-life but is there a definitve answer?

What so ye oh wise CEM fanatics!!! What proof is there ? Cheers, Col ninny

I don't know what the people are coding into IL2, but I am an expert on the internal combustion engine in real life and the main thing to remember is that wear and stress with an internal combustion engine or ANY mechanical device goes up exponentially with speed.

This means that running at 2000rpm instead of 1000rpm is not going to double the wear, stress and heat from friction, it will at least quadruple it.


Some kinds of damage will stop an engine much more quickly than others, for instance running without oil could stop an engine in seconds, while running it with no coolant might let it run for minutes.

Running with broken parts will could increase engine vibration which could literally shake the engine to pieces along with the aircraft, or tear the engine right off the aircraft.

The severity of oil and coolant leaks will also play into how long the engine will run before it stops.

But in every case the more throttle and boost and rpm used with a damaged engine, it will exponentially shorten how long before it stops running.

I don't know how "mechanical" the damage model is, it may be modelled with zero regard to actual engine architecture.

Depends somewhat on the engine design. A water-cooled engine is going to seize fairly quickly as coolant runs out, so you have a very limited lifespan regardless of whether you run it hard or light. A water-cooled engine is not just an air-cooled engine with a cooling system, it has been designed to run significantly hotter to make more power, the cooling system is _required_ to prevent the combustion chamber (piston/cylinder/head) from warping. But in reality that time span will depend on where the leak is in the cooling system.

An air-cooled engine is likely to run for a while until the oil has run out. If an upper cylinder has been torn off the engine but the sump is intact the engine may run indefinitely despite the damage. If the engine is not damaged at all, but an oil feed line has been cut, the engine will run just fine while it pumps the sump dry, then it will seize. Even a water-cooled engine that takes a shell through the block below the water jacket will likely run for a while, even if the conrod is broken, as long as there is still oil in the sump.

Much like fuel leaks, if you have engine damage that is only causing fluid leakage then you have a time period during which the engine will probably run normally. In this case it may be prudent to push the engine harder for a short period to extend before easing off. If you have a fuel tank leak you might as well go full throttle, the engine is not going to drink fuel faster than it's leaking out.

In the absence of definitive proof or documentation from the game developers, players rely on their own experiences, observations, and personal preferences when handling a damaged engine. Running the engine at 90% power and RPM, as you mentioned, is your preferred approach based on how it feels to you. Other players may have different strategies that work well for them.