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jja66uk1966
09-09-2006, 11:26 AM
Is it possible to change the airspeed and altitude readout from km/h and metres to knots and feet?

jja66uk1966
09-09-2006, 11:26 AM
Is it possible to change the airspeed and altitude readout from km/h and metres to knots and feet?

WB_Outlaw
09-09-2006, 12:09 PM
Yes, map a key to Toggle Speedbar . Each time you press that key it will toggle between knots indicated and feet, MPH (not sure if this is indicated or ground) and feet, and back to km/h indicated and meters.

Note that this does not affect the instrument panel, only the speed bar in the lower left. If that is turned off, then you're out of luck.

--Outlaw.

MaxMhz
09-09-2006, 12:22 PM
AFAIK the instruments display IAS while the Speedbar indicates TAS

EDCF_Rama
09-09-2006, 12:51 PM
wrong

Both instrument and speedbar indicates IAS
Speed gauge in no-cockpit view indicate TAS

WWSensei
09-12-2006, 06:37 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Kuna_:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by EDCF_Rama:
wrong

Both instrument and speedbar indicates IAS
Speed gauge in no-cockpit view indicate TAS </div></BLOCKQUOTE>Correct. http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

Yeah that "comic gauge" (wonder woman view) displays TAS - true air speed. </div></BLOCKQUOTE>

Actually, I wonder about that sometimes. It always seems a bit off from TAS and I don't mean by 4 or 5 kph but by 10-20 sometimes. I think they are using a rough formula for TAS but I'm not quite sure which one...

EDCF_Rama
09-13-2006, 03:13 AM
Every test I've done show it fit with the "standard" formula:
TAS = IAS*(100+Alt/600ft+(T?-TS)/5?)/100
TS = Standard Temperature (15? C)
You can measure the Ground Temperature (T?) on a map with an aircraft with an external Temperature gauge (Wildcat for example). This Temperature is constant for a given map (and don't depend on the time)

Looking the "discrepency" you found, it's probably because you forgot the temperature (which generally makes a difference between 1% and 3%)

BBB_Hyperion
09-13-2006, 03:37 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by WWSensei:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Kuna_:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by EDCF_Rama:
wrong

Both instrument and speedbar indicates IAS
Speed gauge in no-cockpit view indicate TAS </div></BLOCKQUOTE>Correct. http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

Yeah that "comic gauge" (wonder woman view) displays TAS - true air speed. </div></BLOCKQUOTE>

Actually, I wonder about that sometimes. It always seems a bit off from TAS and I don't mean by 4 or 5 kph but by 10-20 sometimes. I think they are using a rough formula for TAS but I'm not quite sure which one... </div></BLOCKQUOTE>

Compression correction most likely .)

WWSensei
09-13-2006, 05:19 AM
Not a compression error as I doubt that is modelled atmospherically in the game. It's most likely Rama's reason. I don't think I accounted for temperature and I was using a more generic based on the old 2% per 1000 feet formula. If I could get the actual air density it would be better but haven't found a way to do so and it would seem the airdensity is in "layers" in this game rather than gradual.

BBB_Hyperion
09-13-2006, 07:26 AM
You can calculate airdensity over heinkel temp gauge .)

First noted the steps on gauge are more detailed than on the hud display so
10 km/h+- steps for exampel but that wouldnt explain discrepancies between gauge and hud. Not sure if it is a bug or feature corrected yet but try to dive the p47 max possible and read hud gauge and instrument gauge.

WWSensei
09-15-2006, 06:53 AM
Well, calculating the air density with Heinkel is fine--if I'm flying the Heinkel. Right now there is no consistent method for retrieving the data. I wish they would add it to devicelink where you could query for it. Done a lot of work with devicelink and just can't fully fathom the thought processes behind what they decided to expose and what they didn't. In some areas you can get excrutiating details on things that don't particularly matter and other things are totally left out...urggggh...

BBB_Hyperion
09-15-2006, 08:25 AM
So true all important info is missing on devicelink for fm analyses maybe for a reason.

1.x y z coords
2.TAS airspeed
3.Air Density
4.all control areas current position
5.aircraft state
6.recordable g force in ntrack
etc

But i made following trick on air density.

It is depending on temperature , so when we have the temp we can get the density. I assumend ISA conditions on Crimea map and started to calculate tas with compression correction until density was fitting.
It doesnt fit everywhere tho . The reason is maybe the 0 level of the maps is not 0 . (for example fly at 0 m and look tas ias difference).

NonWonderDog
09-15-2006, 08:44 AM
Devicelink is for feeding the instrument dials in "real" cockpits. It's not for FM analysis.

There are a couple oddities, but mostly it has everything that you'd want to feed to an instrument.

WWSensei
09-15-2006, 12:39 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by NonWonderDog:
Devicelink is for feeding the instrument dials in "real" cockpits. It's not for FM analysis.

There are a couple oddities, but mostly it has everything that you'd want to feed to an instrument. </div></BLOCKQUOTE>

I know what it's for--I wrote a wrapper for devicelink and use it in my own sim-cockpit, but instruments are not the main reason since not all instrument data is available (like temp when available) yet I have about 4 different methods for selecting/de-selecting engines. Then there is the complete lack of state queries available for several items that should have them (like lights).

Of Hyperion's list above I disagree with #1, #2 can be calculated if I have #3, #4 is available, #5 isn't needed and #6 could be calculated from current data.