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XyZspineZyX
09-04-2003, 03:50 PM
Why constant speed prop planes can run forever at max RPM?? you never have to decrease RPM in FB, just move the throttle below 100% and cool the engine. This is very unrealistic, in RL you can't use max RPM for more than 5 min on most planes, you certainly had to decrease RPM to max continuous setting (if not max cruise) to cool the engine.


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Message Edited on 09/04/0309:54AM by Huckebein_FW

XyZspineZyX
09-04-2003, 03:50 PM
Why constant speed prop planes can run forever at max RPM?? you never have to decrease RPM in FB, just move the throttle below 100% and cool the engine. This is very unrealistic, in RL you can't use max RPM for more than 5 min on most planes, you certainly had to decrease RPM to max continuous setting (if not max cruise) to cool the engine.


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Message Edited on 09/04/0309:54AM by Huckebein_FW

XyZspineZyX
09-04-2003, 04:18 PM
Didn`t tested RPM and WEP time, but one thing that isn`t modelled at all is overboosting/overrevving the engine with those CS props.

There were optimum ranges of RPM-Boost settings, and if those were too far away, engine could be damaged, ie. if too high boost was used on engine with too low RPM, the reduction gear would soon fall apart, being unable to cope with the enourmous torque produced. That`s why pilots were instructed in flight manuals to raise RPM first, and only then the boost...

I would like this to be added, too.

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'Only a dead Indianer is a good Indianer!'

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XyZspineZyX
09-04-2003, 04:43 PM
Vo101_Isegrim wrote:
-
- Didn`t tested RPM and WEP time, but one thing that
- isn`t modelled at all is overboosting/overrevving
- the engine with those CS props.
-
- There were optimum ranges of RPM-Boost settings, and
- if those were too far away, engine could be damaged,
- ie. if too high boost was used on engine with too
- low RPM, the reduction gear would soon fall apart,
- being unable to cope with the enourmous torque
- produced. That`s why pilots were instructed in
- flight manuals to raise RPM first, and only then the
- boost...
-
- I would like this to be added, too.


Yes, this should be added too.

But the problem that after you switch the prop to max RPM in CSP planes ,you never need to change this setting gives an unrealistic advantage in acceleration. No plane should be able to keep max RPM for more than 5 min (no water injection). Right now all CSP planes can do it without any time limit!


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XyZspineZyX
09-04-2003, 05:23 PM
What is up with manual prop-pitch on the 109s? Why does the prop run away at 100% ?


<center><img src= "http://www.luftwaffepics.com/LCBW4/FW190-A0-52.jpg" height=215 width=365>

<center>"We are now in a position of inferiority...There is no doubt in my mind, nor in the minds of my fighter pilots, that the FW190 is the best all-round fighter in the world today."

Sholto Douglas, 17 July 1942

XyZspineZyX
09-04-2003, 09:21 PM
FW190fan wrote:
- What is up with manual prop-pitch on the 109s? Why
- does the prop run away at 100% ?
-
-
- <center><img src=
- "http://www.luftwaffepics.com/LCBW4/FW190-A0-52.jpg"
- height=215 width=365>
-
- <center>"We are now in a position of
- inferiority...There is no doubt in my mind, nor in
- the minds of my fighter pilots, that the FW190 is
- the best all-round fighter in the world today."
-
- Sholto Douglas, 17 July 1942
-

You can have it at 100% in a steep climb. I suggest turning off the auto-pitch before take-off and taking it down to 80%. If you disengage auto in the air, it will be at 100% severely overrev the engine.

--AKD

http://www.flyingpug.com/pugline2.jpg

XyZspineZyX
09-04-2003, 10:22 PM
I don't think somebody flying a constant speed prop plane EVER changed prop pitch from max RPM. This is an awful bug! it should fry your engine in 10 minutes!


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XyZspineZyX
09-04-2003, 10:32 PM
To give an example you can select the 100% trottle and 100% prop pitch on P-47D-10 and go forever without any overheat mesage. In real life, even if you selected max continous MP setting but forgot max RPM, it would be enough to fry your engine in 10 minutes. R-2800 (without water injection) cannot run for more than 5 minutes at 2700rpm without overheating. You should decrease RPM to 2550 to cool the engine. There's no need to do such a thing in FB.

P-47 is not the only example. All constant speed prop planes exhibit the same erroneous behaviour.


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XyZspineZyX
09-05-2003, 05:28 PM
Did somebody ever lowered the prop pitch from 100% on russian planes?
Just asking.


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XyZspineZyX
09-05-2003, 06:15 PM
Huckebein_FW wrote:
- Did somebody ever lowered the prop pitch from 100%
- on russian planes?
- Just asking.
-
-
- <center> <img
- src="http://www.stormbirds.com/images/discussion-m
- ain.jpg"> </center>

Only when I'm trying to land.

--AKD

http://www.flyingpug.com/pugline2.jpg

XyZspineZyX
09-05-2003, 06:18 PM
It can be done. Take most helicopters for an easy example. When they fly, the throttle is always set to its maximum setting. The main rotor always turns at a constant rpm. Both are maintained there due to an engine governor. Increasing the collective lever increases the rotor pitch, engine speed, engine temperature and torque (similar effects to a throttle in a plane). The effect is that this increases the rate of climb and/or helicopter's speed.

Performance is limited by either maximum Torque, Engine speed or Engine Temperature, dependent on all up weight, outside temperature, type of chopper, etc. This limitation will determine your maximum continuous power. On the 7 choppers that I have flown, you can select maximum continuous power for "x" minutes or seconds, yet your rotor speed will not change. You can reduce your power setting to below max continuous for "x" seconds to "cool off", then start the process all over again. Granted, 6 of these helicopters had turbine engines, but one was of piston type.

In flying the P-47 in this game, a constant max power setting will create an overheat situation after "x" minutes, dependent upon altitude (and outside temperature). "x" seconds of cooling will allow for max power once again, but for a much shorter duration. The process can be repeated a few times, with cooling cycles taking longer and max continuous power times becoming shorter, until power needs to be massively reduced to properly cool the engine. This took many minutes to do in former patch.



Message Edited on 09/05/0305:21PM by ISU-152

XyZspineZyX
09-05-2003, 06:30 PM
ISU-152 wrote:
- It can be done. Take most helicopters for an easy
- example. When they fly, the throttle is always set
- to its maximum setting. The main rotor always turns
- at a constant rpm. Both are maintained there due to
- an engine governor. Increasing the collective lever
- increases the rotor pitch, engine speed, engine
- temperature and torque (similar effects to a
- throttle in a plane). The effect is that this
- increases the rate of climb and/or helicopter's
- speed.
-
- Performance is limited by either maximum Torque,
- Engine speed or Engine Temperature, dependent on all
- up weight, outside temperature, type of chopper,
- etc. This limitation will determine your maximum
- continuous power. On the 7 choppers that I have
- flown, you can select maximum continuous power for
- "x" minutes or seconds, yet your rotor speed will
- not change. You can reduce your power setting to
- below max continuous for "x" seconds to "cool off",
- then start the process all over again. Granted, 6
- of these helicopters had turbine engines, but one
- was of piston type.
-
- In flying the P-47 in this game, a constant max
- power setting will create an overheat situation
- after "x" minutes, dependent upon altitude (and
- outside temperature). "x" seconds of cooling will
- allow for max power once again, but for a much
- shorter duration. The process can be repeated a few
- times, with cooling cycles taking longer and max
- continuous power times becoming shorter, until power
- needs to be massively reduced to properly cool the
- engine. This took many minutes to do in former
- patch.


Thanks for the lesson buddy, but it's no use to compare modern turboshafts with ww2 piston engines. NO ENGINE could be run for more than 10 minutes at max RPM.

You can run forever at 100% throttle and 2700rpm in P-47. You want to convince me that this is correct?


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Message Edited on 09/05/0312:35PM by Huckebein_FW

XyZspineZyX
09-05-2003, 07:00 PM
1. Never said anything could exceed 10 minutes at max RPM.

2. I wouldn't call 1959 and 70's technology modern either.

3. I find that this game does not portray manifold pressures properly, which affects related aircraft capabilities. If you want the real world answer however, talk to =353=MONROEQ, who actually flew P-47s during WW2.

Cheers@

XyZspineZyX
09-05-2003, 07:15 PM
At 100% pitch setting, the Constant Speed props are not running at their redlne speed. They are running below it, and it is a quite functional range for them to be in.

To my understanding, with the way the RPM settings are handled in the current patches, it is very difficult to actually run the RMP up to the red zone with the constant speed props. Manual pitch props are a different matter, however.

Harry Voyager

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XyZspineZyX
09-05-2003, 07:18 PM
Many thx HarryV - I usually fly cockpit off anyway.