[sabreclaw]

I don't know if this is a sturmovik or pilot (me) problem but it seems to be impossible for me to build up speed records in IL-2 stiurmovik. I've noticed that almost every speed record each plane has been achieved in high altitudes, in between 3,000 and 9,000m and yep, i've tried that myself too but it seems to be impossible to build up speed even near those record numbers in IL-2. For example: P-47, as wikipedia says, has maximum speed of 433 mph at 30,000 ft (697 km/h at 9,145 m) but when i try that my plane won't reach even 500km/'h - same thing seems to happen in every plane i've tried. What am i doing wrong or is that just IL-2 problem? It's kinda fun to see how a high altitude interceptor barely stays in the air in those numbers.

And about the superchargers.. Is there a trick to activate higher level superchargers on planes such as P-47D, P-38J or Fw-190A or didn't they just have manually controlled ones?

[aviatorsneah]

first off these records you see are going to be given in true air speed. what you are most likely seeing in IL2 (as seen on instruments) is indicated airspeed which is always going to be a lot lower than TAS at higher altitude. "barely staying in the air" at those altitudes is because your IAS is lower in the lower-density air, but don't worry, you are still cookin' along at a higher TAS. Also, if you have advanced engine management on, you might not be managing mixture or superchargers correctly for that altitude.

try the search...there have been a few threads on here discussing this.

point is...it's pretty accurate to real world data.


as for superchargers, if you have advanced engine management turned on, you can control the superchargers setting, but you must assign a key to do it. I think i have Shift+S for increasing the supercharger stage, and Ctrl-S to decrease, but you may put whatever you'd like.

[_VR_Aristo]

What aviatorsneah said, but I personally think those speeds are actually ground speeds rather than true air speeds.

And for the planes you're asking; P-47(which I'm surprised you don't know since you obviously read the wiki page), P-38, Fw-190, P-63, P-51 and so on... all these aircraft either have turbosupercharger or two-stage superchargers with automatic clutch, neither of which the player can manipulate in the game. So it's all automatic

Aristo

[Cuccos19]

As far as I know, the turbocharger cannot set in the game. I don't know what is for the live ones. I know for example the P-47 and F4U was equipped with the quite same engine - PW R-2800 (I don't know the exact subtypes). The P-47 had turbocharged engine and the F4U had mechanically supercharged engine. The turbo was better suited for high altitude operations, so the Jug was better at higher altitude than the Corsair.

Here it goes: http://en.wikipedia.org/wiki/Turbocharg ... ercharging

[aviatorsneah]

What aviatorsneah said, but I personally think those speeds are actually ground speeds rather than true air speeds.

not true.

ground speed = true airspeed +/- tailwind/headwind component respectively.

so with no wind they are the same.

previous posts are correct with the superchargers...with some airplanes they are automatic.

[.041 Safety Wire]

As far as I know, the turbocharger cannot set in the game. I don't know what is for the live ones. I know for example the P-47 and F4U was equipped with the quite same engine - PW R-2800 (I don't know the exact subtypes). The P-47 had turbocharged engine and the F4U had mechanically supercharged engine. The turbo was better suited for high altitude operations, so the Jug was better at higher altitude than the Corsair.

Here it goes: http://en.wikipedia.org/wiki/Turbocharg ... ercharging

Actually, The P-47 was turbosupercharged with a turbo mounted in aft fuselage and an internally driven supercharger. All r-2800,s have an internally driven supercharger and most of the Corsairs had two speed/two stage superchargers.

[_VR_Aristo]

Actually, The P-47 was turbosupercharged with a turbo mounted in aft fuselage and an internally driven supercharger. All r-2800,s have an internally driven supercharger and most of the Corsairs had two speed/two stage superchargers.

Correct... It's not turbocharger, but "turbosupercharger". On the F4U; altough it was two-speed in reality, in game, interestingly it has three-speed supercharger?!

And I stand corrected on the speed issue, thanks aviatorsneah.

Aristo

[{HVY-E}Jinxx]

What aviatorsneah said, but I personally think those speeds are actually ground speeds rather than true air speeds.

not true.

ground speed = true airspeed +/- tailwind/headwind component respectively.

so with no wind they are the same.

previous posts are correct with the superchargers...with some airplanes they are automatic.

Not true again.......

You are partially correct (TAS does differ according to windspeed/direction), but for a true representation of TAS vs. IAS you need to think in particles. The reason you are faster at alt vs. at sea level is air density (Thicker air).

Everything is made of particles (atoms), the more you have, the more weight, friction you have.

For our example, let's just work with friction.

- You fly along at sea level at 350mph.
- You fly along at 30,000ft at 430mph.

This is because the air is thinner and your plane has less drag (less friction due to air density) at that alt. Thus it is easier for the plane to slip through the air. The reason you can't get a proper reading on the gauges is due to particle density.

Think of the air like a bunch of balls. At sea level you have 200 balls all around you at any given time and need to have appx. 200 balls pass through the pitot tube in order to cause enough pressure and get a reading of 200mph. Easy to do because the air is denser (more balls) at sea level.

At 30,000ft. you still need the same number of balls to pass through the pitot tube, but there are only 175 balls around you at any given time, (thinner air = less dense), so you have to go faster to get the same reading in the pitot tube. You finally get fast enough to get the reading you're looking for, 200mph, but you've had to pass through all 175 balls and then back through 25 more again in order to get the same reading, so you are really going 25mph faster in order to get the same reading.

Hope I didn't confuse you too much.

S!

[.041 Safety Wire]

Actually, The P-47 was turbosupercharged with a turbo mounted in aft fuselage and an internally driven supercharger. All r-2800,s have an internally driven supercharger and most of the Corsairs had two speed/two stage superchargers.

Correct... It's not turbocharger, but "turbosupercharger". On the F4U; altough it was two-speed in reality, in game, interestingly it has three-speed supercharger?!

And I stand corrected on the speed issue, thanks aviatorsneah.

Aristo

Actually the Corsair has a two speed two stage. Supercharger impellers are mounted back to back within the supercharger case and there is a considerable size difference between the two.

[hal]

Hi guys,
On the topic of IAS/TAS.

IAS is the displayed value on the ASI.

RAS/CAS is IAS corrected for instrument and pressure error.

TAS is CAS corrected for density and pressure error.

GS is TAS corrected for wind component

There is also EAS which is CAS corrected for pressure error only(compressibility effect when over 300 kts)

i don't think instrument error is modeled in il2 but to find accurate TAS and GS you need altitude, temperature, wind speed and a flight computer like this
http://en.wikipedia.org/wiki/E6B. The speeds actually do come pretty close
I'm sure i've seen some pics of a vintage luftwaffe flight computer somewhere but can't find them now..