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devill102yu
07-10-2004, 04:04 AM
P47 has a gauge labeled "turbo" (rpm) but it never shows anything else than 0. I guess it is for the turbocharger. So if its automatic the turbo should kick in at some altitude and that should show on the gauge. Now, climbing the p47 one cant see any change in mainfold pressure gauge that would indicate that super or turbocharger was activated at any alt. You onlu get a drop in pressure at certain alt.
What gives? Turbocharger non existant in p47 or gauge isnt active?

devill102yu
07-10-2004, 04:04 AM
P47 has a gauge labeled "turbo" (rpm) but it never shows anything else than 0. I guess it is for the turbocharger. So if its automatic the turbo should kick in at some altitude and that should show on the gauge. Now, climbing the p47 one cant see any change in mainfold pressure gauge that would indicate that super or turbocharger was activated at any alt. You onlu get a drop in pressure at certain alt.
What gives? Turbocharger non existant in p47 or gauge isnt active?

pcisbest
07-10-2004, 04:16 AM
I asked this a while back, seems no one could give me a straight answer. I guess it just isnt modelled, why I dont know. Also, still cant figure why I cant manually adjust the turbo or the fuel mixture on P-47.

Cajun76
07-10-2004, 04:32 AM
It seems to be modeled, because the P-47 dosen't lose power at high alt, but the guage dosen't work. IRL, IIRC, the turbo worked all the time, a waste gate controlled how much air was sent to it. Early models I believe were manual for mix and prop, but later ones used coordinated linkage, so everything was automatic. At high alt, to keep the turbo from overspeeding, the pilot would actually throttle back to keep it in the safety zone.

http://www.zenoswarbirdvideos.com/P-47.html

http://rwebs.net/avhistory/history/p-47.htm

Good hunting,
Cajun76

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What if there were no hypothetical questions?

pcisbest
07-10-2004, 04:45 AM
Yeah, I know how the turbo works, that the waste gate was autmatically adjusted during flight, but the pilot could also use a control lever to adjust the supercharger if need be, must be why there is a big, fat lever with "Supercharger" written on it right next to the throttle. Curiously, if you look at this lever in-game, it is set to the "OFF" position? Also, whatever the justification is for not modeling the supercharger control, I dont see why we cant adjust mixture, those films from the P-47 training show mixture being adjusted, along with RPM and the initial turbo settings.

Cajun76
07-10-2004, 05:11 AM
We used to have strictly manual fuel mix, but that was inaccuarate. Check near the very bottom of the "rwebs" websight for some info on the throttle linkage and how the supercharging system is "controlled" by the pilot. Initial setting and shutoff positions of fuel, rpm, turbo, and other things are handled by the "I" key for all planes. http://ubbxforums.ubi.com/images/smiley/16x16_smiley-wink.gif

Good hunting,
Cajun76

http://img12.photobucket.com/albums/v30/Cajun76/p47nh.jpg
What if there were no hypothetical questions?

Jambock__01
07-10-2004, 06:58 AM
I worked in the research of the P-47 for FB and talked to an WWII brasilian veteran who flew P-47 over Italy in 76 war missions. He told me D-25 was suposed to have manual turbocharger and must be turned on at 3.000 mts, but they use to take off with the turbo ON.

Take a look at the left side of the cackpit and you will see the Turbocharger shift.

Why it dont work in FB? I think Oleg simply dont want. We provided several fonts and references with the completed model.

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ForkTailedDevil
07-10-2004, 07:40 AM
I am not a airplane expert. But I do know quite a bit about turbocharged automobiles. Can someone explain how you could turn a turbo on and off in flight? This is a turbo we are talking about and not a supercharger right?

"You can teach monkey's to fly better than that"

VW-IceFire
07-10-2004, 08:16 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by ForkTailedDevil:
I am not a airplane expert. But I do know quite a bit about turbocharged automobiles. Can someone explain how you could turn a turbo on and off in flight? This is a turbo we are talking about and not a supercharger right?

"You can teach monkey's to fly better than that" <HR></BLOCKQUOTE>
I don't have the answer but the P-47 used a tubersupercharger so it has both in effect working for it.

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p1ngu666
07-10-2004, 08:45 AM
end result is the same tho
wish we had hot rodded p47s http://ubbxforums.ubi.com/images/smiley/16x16_smiley-happy.gif
need a warning of "danger to manifold http://ubbxforums.ubi.com/images/smiley/784.gif" tho http://ubbxforums.ubi.com/images/smiley/16x16_smiley-very-happy.gif

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IL2-chuter
07-10-2004, 11:16 AM
[QUOTE]Originally posted by ForkTailedDevil:
I am not a airplane expert. But I do know quite a bit about turbocharged automobiles. Can someone explain how you could turn a turbo on and off in flight? This is a turbo we are talking about and not a supercharger right?



The waste gates on a Jug are located behind the cowl in front of the wing where you would expect the exhausts to be. The exhaust is in front of the tailwheel in a backward facing "scoop" (that Kelly Johnson couldn't get to work for P-38 - thrust recovery). To turn "off" turbo, simply open waste gate valves all the way and that will dump the pressure behind the turbo and you'll have no significant turbo spool-up. At Ie Shima, the Republic factory rep was alarmed to find out everyone there was taking off with 56 inches boost. He tried to convince everyone they should be sticking to the book's 52 inches and arranged a demonstration where a typically loaded (for the squadrons at Ie Shima) Jug took off at the preferred settings (I don't recall if the rep or an army pilot was flying), wallowed along awhile, then crashed some distance beyond the runway. The pilots, unimpressed, stuck with their "full throttle" (56") technique.

With the US military, "the book" wasn't always followed, so you have "overload weights" and "local flying techniques" that become sort of a "book addendum" if they are acknowleged by the military, but otherwise only turn up in veteran recollections or maybe unit histories.

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pcisbest
07-10-2004, 01:58 PM
Yeah, there is little basic difference between a turbo supercharger and a regular supercharger. The turbo simply has a turbine driven by the hot exhaust gases of the engine, this turbine in turn drives a standard centrifugal blower. In a regular supercharger, you have step-up gears from the engine itself drive the blower, or blowers, depending on wheather it is single or two stage.

The P-47 had the exhaust gases drive the gas turbine, and this flow of gas could be admitted or constricted by a waste gate that ran ulitmately to a duct at the rear of the aircraft, as IL-2 Chuter described. The P-47 also had a second, mechanically driven blower to compliment the first one if I am remembering right.

VMF-214_HaVoK
07-10-2004, 02:30 PM
Been flying the Jug since 1.0 FB and never has the gauge or SC seemed to work. It has been brought up several times to Oleg and team but has never been fixed. With all other planes that have automatic super chargers you can hear them engage when passing the alt that they are set for, with the JUG you hear no change in power. So does it work? Maybe, it doesnt seem to loose too much power at high alt. But! If it is not working wouldnt it be even better at high alt as it should be? Hopefully Oleg and team will finally address this issue in the next patch, but I find it unlikely. Oleg always seems reluctant and has to be hammered with facts to make any realistic changes to US aircraft. Maybe in PF http://ubbxforums.ubi.com/images/smiley/16x16_smiley-wink.gif

=S=

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IL2-chuter
07-10-2004, 05:20 PM
Don't know if turbo works . . . http://ubbxforums.ubi.com/images/smiley/16x16_smiley-sad.gif

You won't have a shift on Jug because Super is single speed relying on Turbo to raise critical altitude. If it's modelled in game it would show as a maintainance of manifold pressure to the critical altitude of Jug, don't know what that is right off. IRL you could use the turbo a bit low down to overboost the engine (as in 56 inches). That we don't have. http://ubbxforums.ubi.com/images/smiley/16x16_smiley-mad.gif

Note: Modern turbo turbines are all centrifugal style, WW2 GE's were axial http://ubbxforums.ubi.com/images/smiley/16x16_smiley-surprised.gif.

"I fly only Full Real in Il2 Forgotten Battles." -Mark Donohue