[NO BUG] Radiator coolant too hot too quickly

[Xxx]

With a modest combat boost of 8, the radiator coolant temps go 140+ and result in flames emitting from the exhaust ports.

 

 

Please review the effectiveness of the radiator flaps, even with them wide open manually the aircraft will die after 60 seconds?

 

 

This occurs with low ambient air temps.

 

 

Regards

David

[OnlyforDCS]

Accipiter, at what speeds? Listing a boost setting without indicated speed is not giving a full report of what happened. I've yet to blow a Spit engine without it being my fault. I can run it at full boost all day long actually. (Well as long as I have fuel).

[razo+r]

What was your speed and the outside temperature?

[philstyle]

What was your speed and the outside temperature?

 

 

 

I don't think the spit has an OAT guage does it?

[razo+r]

I don't think the spit has an OAT guage does it?

 

No but it's in the briefing

[flare2000x]

Your RPM will affect the temperature. Keep it under 2800 or else you'll heat right up. If you're just cruising at 3000 that's a recipe for disaster.

[philstyle]

No but it's in the briefing

 

 

 

OK. But that's only the air temperature at sea level right? It doesn't provide graduated temps as the altitude increases in the briefing does it?

[razo+r]

OK. But that's only the air temperature at sea level right? It doesn't provide graduated temps as the altitude increases in the briefing does it?

 

It only has the air temp in, which is set in the mission editor. I assume this is the hottest temp in that mission and since we don't know how high, how and where OP flew, you could say that maybe the outside temperature was too hot and not the pilots fault

 

.... Keep it under 2800 or else you'll heat right up. If you're just cruising at 3000 that's a recipe for disaster.

 

Not necessary. If it is a hot day then yes, if it cold than you can let it run at 3K just fine

[Holbeach]

OK. But that's only the air temperature at sea level right? It doesn't provide graduated temps as the altitude increases in the briefing does it?

 

Subtract 2 deg C, for every 1000' above sea level temp.

 

..

[Holbeach]

I have climbed multiple times to 42,000' at 3000 rpm and full throttle with rad on auto and never overheated.

 

Just keep the speed above those stated in the manual.

 

..

[DSSRapidfire]

I have climbed multiple times to 42,000' at 3000 rpm and full throttle with rad on auto and never overheated.

 

Just keep the speed above those stated in the manual.

 

..

 

you sure you're in sim mod and not simple?

[Holbeach]

I've never used simple mode.

 

I flew it again to 35,000' in same condition.

 

Sea level temp was 15 deg.

 

Water temperature was generally around 125 deg, with a max. of 132 deg.

 

The real Spit could do this and so can ours. Just keep the speed up.

 

P.S. Maybe the OP is in Normandy, where unusual behaviour is being reported.

 

..

Edited May 30, 2017 by Holbeach

[Art-J]

I have to agree with Holbeach here, at least for the 2.1. on NTTR map, cause I don't own Normandy yet.

 

Yesterday I tried to do a "torture-test" in instant takeoff mission, deliberately trying to kill the engine to check if the rumble sound known from P-51 can be heard in the Spit and to see the new engine fire effect people are talking about.

 

Sadly, couldn't do it - at first I pushed the throttle wide open, RPM to max, steep climb with speed dropping to 150-160. True, both temps topped the gauges, but as nothing happened till well over 15k ft, and at these speeds I started stalling up high anyway, I decided to get back to the deck and do some silly low-flying in tight circles below 180 mph, all the time on the edge of stalling. Temps went through the roof again but after a couple of minutes of this idiotic merry-go-around I lost patience, gave up and got back to base.

 

Don't know what ambient conditions are in this particular missions, but I expected some fiery problems while abusing the engine over the damn desert!

 

 

Could it be that the plane overheats faster over Normandy for some peculiar reason?

Edited May 30, 2017 by Art-J

[philstyle]

Could it be that the plane overheats faster over Normandy for some peculiar reason?

 

Interesting question for you and Holbeach.

 

 

I have both NTTR and Normandy maps.. so I might (if I find time/ remember) try to set up like-for-like conditions and do some testing.

[Holbeach]

Interesting question for you and Holbeach.

 

 

I have both NTTR and Normandy maps.. so I might (if I find time/ remember) try to set up like-for-like conditions and do some testing.

 

The OP has asked the same question in Normandy, where he is hanging off the prop at zero speed and blowing the engine, in which case the answer would be the same in both maps.

 

Keep the speed up.

 

..

[312_JS]

I have to agree with Holbeach here, at least for the 2.1. on NTTR map, cause I don't own Normandy yet.

 

Yesterday I tried to do a "torture-test" in instant takeoff mission, deliberately trying to kill the engine to check if the rumble sound known from P-51 can be heard in the Spit and to see the new engine fire effect people are talking about.

 

Sadly, couldn't do it - at first I pushed the throttle wide open, RPM to max, steep climb with speed dropping to 150-160. True, both temps topped the gauges, but as nothing happened till well over 15k ft, and at these speeds I started stalling up high anyway, I decided to get back to the deck and do some silly low-flying in tight circles below 180 mph, all the time on the edge of stalling. Temps went through the roof again but after a couple of minutes of this idiotic merry-go-around I lost patience, gave up and got back to base.

 

Don't know what ambient conditions are in this particular missions, but I expected some fiery problems while abusing the engine over the damn desert!

 

 

Could it be that the plane overheats faster over Normandy for some peculiar reason?

I've destroyed the engine right after a take off by taking off with a cold engine on the Normandy map the other day.

[Yo-Yo]

I have climbed multiple times to 42,000' at 3000 rpm and full throttle with rad on auto and never overheated.

 

Just keep the speed above those stated in the manual.

 

..

 

Right. By the way, most of cooling tests were perfromed at OAT less than standard and then, if necessary, reduced to standard atmosphere.

[Xxx]

Although I still think the Merlin should last longer than 2 minutes at a boost of 8 in a sea level climb, here are some hair raising figures of what the Merlin is doing in just one second!

 

In that one second, the V-12 Rolls-Royce Merlin engine would have gone through 60 revolutions, with each of the 48 valves slamming open and closed 30 times. The twenty four spark plugs have fired 720 times. Each piston has traveled a total of 60 feet in linear distance at an average speed of 41 miles per hour, with the direction of movement reversing 180° after every 6 inches. Three hundred and sixty power pulses have been transmitted to the crankshaft, making 360 sonic booms as the exhaust gas is expelled from the cylinder with a velocity exceeding the speed of sound. The water pump impeller has spun 90 revolutions, sending 4 gallons of coolant surging through the engine and radiators. The oil pumps have forced 47 fluid ounces, roughly one-third gallon, of oil through the engine, oil cooler, and oil tank, scavenging heat and lubricating the flailing machinery. The supercharger rotor has completed 348 revolutions, its rim spinning at Mach 1, forcing 4.2 pounds or 55 ft³ of ambient air into the combustion chambers under 3 atmospheres of boost pressure. Around 9 fluid ounces of high octane aviation fuel, 7,843 BTUs of energy, has been injected into the carburetor along with 5.3 fluid ounces of methanol/water anti-detonant injection fluid. Perhaps 1/8 fluid ounce of engine oil has been either combusted or blown overboard via the crankcase breather tube. Over 1.65 million foot pounds of work have been done, the equivalent of lifting a station wagon to the top of the Statue of Liberty.

In that one second, the hard-running Merlin has turned the propeller through 25 complete revolutions, with each of the blade tips having arced through a distance of 884 feet at a rotational velocity of 0.8 Mach. Fifteen fluid ounces of spray bar water has been atomized and spread across the face of the radiator to accelerate the transfer of waste heat from the cooling system to the atmosphere.

 

The Merlin, no wonder it sounds like a soul in torment?

 

Regards

 

David