Spit IIa Performance graph

[bongodriver]

Originally Posted by CaptainDoggles

I thought we decided that the atmosphere in game was way off the mark?

Not completely, there is a setting on the FMB which brings the atmospheric temparatures in line with ISA, but by default it seems the atmosphere is modelled as ISA + 10 which is perfectly feasible in the real world in summer time, with ISA +10 we can expect to see an underperformance from what is stated in aircraft flight manuals, the results of my atmospheric tests are in the hurricane speed thread.

http://forum.1cpublishing.eu/showthread.php?t=32523

at some point I wan't to check the pressure lapse rate but I don't think it makes for as big an issue as temparature.

[CaptainDoggles]

Originally Posted by bongodriver

but by default it seems the atmosphere is modelled as ISA + 10 which is perfectly feasible in the real world in summer time

That might be a map-wise setting, hard-coded lke we used to see in 1946. Be interesting to test if/when BoM comes out.

[bongodriver]

Originally Posted by CaptainDoggles

That might be a map-wise setting, hard-coded lke we used to see in 1946. Be interesting to test if/when BoM comes out.

did you check that thread I mentioned? the Breeze/thermal factor slider in mission parameters in the FMB changes the temparatures and set it to 0 you get pretty much standard conditions, with further experimentation I'd like to find out if there is a way to get ISA - conditions.

[CaptainDoggles]

Originally Posted by bongodriver

did you check that thread I mentioned?

I did, yes.

What I meant was that, perhaps the slider in FMB allows us to change the pressure in the relative sense.

I.e. The difference between 0 and 10 on that slider might not produce ~ISA and ISA+10 on a different map, which is what I meant by "map-wise setting"

It will be nice in a couple of years to if/when we get some FMB documentation.

[Crumpp]

We know the lapse rate is 1.98C/1000ft, right?

Set the altimeter to field elevation and read the window to get pressure. It is close enough.

Have someone spawn with an aircraft that has an OAT gauge and read the temp at that field elevation.

You have the data required to convert the performance for that map.

[bongodriver]

Originally Posted by CaptainDoggles

I did, yes.

What I meant was that, perhaps the slider in FMB allows us to change the pressure in the relative sense.

I.e. The difference between 0 and 10 on that slider might not produce ~ISA and ISA+10 on a different map, which is what I meant by "map-wise setting"

It will be nice in a couple of years to if/when we get some FMB documentation.

Ultimately I think you are right on that one, the sliders effect is probably coincidental, it really seems geared around some basic enviromental effects, you can set layers or bands of the effect at varying altitudes, my guess it is just for simulating turbulence at varying levels and the associated air temparature mixing.

[Crumpp]

so, takeoff weight = maximun takeoff weight

No it is the weight of the aircraft configuration you are flying.

Note the weight of the plane @ take off and not "maximum take off weight" as per the POH.

[Crumpp]

There is a control somewhere to set the temperature and pressure. If you can set them too:

SL Temperature 15C
SL pressure 1013.25mb

So this control slider does not exist to set conditions to standard?

associated air temparature mixing

What needs to happen is a plane with and OAT takes some readings at altitude.

Then you know for sure.