Coolant and Aftercoolant Relief Valves Missing

Quite simply, where are they? Why aren't they on our Mustang in DCS now? Missing documentation? Overlooked? I'm not sure of what the pressure had to be for the coolant to get released, but there are two relief valves.

Both systems work with certain pressure and if their limits are overcome, they relieve overpressure from particular system.

They simply protect systems from any possible damage which can be caused by overpressured coolant liquid (or vapour).

picture is from TO 01-60JE-2 Erection and Maintenance Instructions for Army Models P-51D-5 and says only exact pressure for aftercooler relieve.

As said in the title, it's missing. This is not represented in DCS. I have never seen this in DCS: P-51D at any time.

Thanks for the input, though. Didn't know the pressure.

Below is taken from "To Fly and Fight: Memoirs of a Triple Ace". Hopefully with the new damage model that's being released we'll finally get to see realistic engine overheat modelling:

Below is taken from "To Fly and Fight: Memoirs of a Triple Ace". Hopefully with the new damage model that's being released we'll finally get to see realistic engine overheat modelling:

 

Funny - to my blurry eyes both blue vent lines look to come from the valves out onto the sides of the nose by the exhaust manifolds...

There is an engine overheat damage model that presumably takes a number of failure modes into account. (I'm not saying this is one of them, but there are a number of modes of system failure that are explicitly taken into account in DCS that have no visual representation...)

As far as a quick google and 30 seconds of excel indicate to me though, with a 20psi load & 70% glycol that aftercooler valve should crack a bit north of 130 degrees (very roughly).

Be interesting to know the pressure for the coolant system proper.

In SIM if you hold your engine temps at or above that temp long enough, you will see an adverse effect...

Explicitly modelling coolant boil-off as a failure mode would raise the question (raised by the pilot, who apparently had no idea) of how much fluid the system can loose before it impacts the system's ability to dump heat, and how quickly that ability degrades as the volume falls below that point.

Presumably you could lose everything in the radiator header tank(s) before any loss of effectiveness (that's part of why they're there). That would be quite a spectacular ejection.

But you'd have to know how much coolant is expelled when the system initially vents, and how much volume is lost to boiling after that.

Boiling off the header tanks would be a lot of steam over a reasonable amount of time - remembering that the valve doesn't drop the pressure to zero, only stops it getting above 20psi, so the engine would just slowly boil off coolant, not have the entire system suddenly boil.

Purging everything between the cylinder vaults and the valve might be quite a lot quicker.

Also - If other modes of failure are likely to have occurred before the volume of coolant loss impacts the cooling system's ability to remove heat, then modelling this mode would be effectively redundant, and only there for 'visual completeness'.

To know whether this was the case would need the notes from destructive testing set up for this purpose.

If this information wasn't available, the failure mode wouldn't be able to be modelled accurately.

Anyone seen a video of this occurring ?

If this information wasn't available, the failure mode wouldn't be able to be modelled accurately

I think this is one of those circumstances where its better for the simulation to be a reasonable physical approximation if the required data is unavailable, compared to being completely wrong as the current implementation is.

its better for the simulation to be a reasonable physical approximation if the required data is unavailable

But with no documentation = what would that be* ?

Specifically - How would over temp engine failure rates differ from those currently modelled ?

(*Apart from a visual spray of coolant of some unknown volume at a coolant temp of around 135 degrees)