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stitchjones1971
02-07-2007, 07:34 AM
I've been flying the Zero around and I get the engine overheat warning more often than not. I see there are different radiator postions (2, 4, 6, 8, OPEN and CLOSED).

1) Does having the radiator open affect performance?
2) What are the differences in these postions?
3) Does anyone have any techniques as to when to use it and when not to use it?

Thanks!!

TgD Thunderbolt56
02-07-2007, 07:53 AM
I keep the rad closed when climbing out. Once I get some decent altitude (maybe 2k), I'll open my rad ALL THE WAY and throttle back to about 85% to avoid overheat. I then climb a bit more shallow and try to keep my airspeed up. Once I'm at the altitude I want, I close my rad as long as my throttle isn't over 85%. This way, I can throttle up in an engagement and not overheat for at least a few minutes.

The use of the stepped radiator does effect performance and DOES effect the rate at which your engine will overheat but in my experience, it much better to practice a bit of preventive maintenance and not allow your engine to overheat in the first place. Because needing to breathe your engine and cool it down in the middle of a fight is the last thing you want.


TB

Chris0382
02-07-2007, 07:56 AM
Dont mean to hijack but can the radiator opening and closing effects be seen with a temp guage.

R988z
02-07-2007, 08:09 AM
Originally posted by stitchjones1971:
I've been flying the Zero around and I get the engine overheat warning more often than not. I see there are different radiator postions (2, 4, 6, 8, OPEN and CLOSED).

1) Does having the radiator open affect performance?
2) What are the differences in these postions?
3) Does anyone have any techniques as to when to use it and when not to use it?

Thanks!!

1. yes it creates more drag, so slower top speed when it is open. Some aircraft seem more affected than others. The 109F onwards with the split flap radiator tends to be quite noticeable. You particularly notice at cruise when the difference between radiator open and radiator closed is probably a good 20-30km/h.

2. I've always assumed:
closed = closed (believe it or not!)
pos. 2 = 25% open,
pos. 4 = half open,
pos. 6 = 75% open,
pos. 8 = 100% open
open = 100% open
auto = open most of the time anyway.

although it might be that pos 2 = 20%, 4 = 40%, 8 =80% and open is fully open, I've never really checked but it's not that critical a difference.

3) Generally keep radiator open from the time you start the engine and most of the climb.
When you throttle back for cruise keep the radiator closed or position 2. When you need maximum speed (whether dive or straight line) keep it closed. After you have done some full throttle combat for a few minutes, throttle back and open radiator to either half or even full, let the engine cool. Much better to prevent the overheat than wait for the message. Once it has overheated it will do so again quickly. When landing it's a good idea to open radiators as well, to create some extra drag to assist the slow down.

It also helps to to set prop pitch at a lower percentage to help stave off overheat, around 85% on a Zero is fine in my experience, set it lower for long distance cruise, higher for close combat.

The higher you are and the faster you are going the better the cooling usually. It's mainly low speed turn and burning at constant full throttle and high prop pitch settings that cause overheat problems.

Some R2800 powered aircraft like the P-47 and Hellcat don't have functioning radiators from what I understand (a game bug) and so you are best to leave these closed all the time and keep throttle settings lower in cruise. Those big torquey engines love the lower prop pitch settings anyway.

Later model spitfires just have a huge radiators that you can't open or close, it works well enough that it rarely overheats even with savage use of the throttle.

Mosquitos also have only two settings, open and closed.

the Bf109E/Z with nitrous will overheat when you hit the Nitrous injection at too low an altitude, this pretty much kills your engine, no amount of radiator fiddling will fix this.

The jets dont have any radiators (obviously) but you will still get overheat in some situations. Usually this is when you are going to slowly with too high a throttle setting. Keep throttle below 80% when climbing after take off in a jet and wait for speed to get to around 500km/h or so and a decent altitude. Once you are going this fast then you can use full throttle if need be without overheating worries. Just be mindful that if your speed drops again and you keep throttle on high it will likely overheat again.

That's all the quirks I can think of that are in this game in regard to cooling systems.

major_setback
02-07-2007, 09:07 AM
I notice I can turn a bit tighter, and generally find aircraft more manoeuvrable with the radiator closed.
I leave it open whenever possible, closing it before combat.