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- IL-2 Sturmovik: Cliffs of Dover (http://forum.fulqrumpublishing.com/forumdisplay.php?f=189)

- - Bf109 test data (http://forum.fulqrumpublishing.com/showthread.php?t=34816)

Quote:

Originally Posted by Kurfürst (Post 468689)

BTW how do you measure TAS?

There are two ways I use.

One is to take the CoD C# Parameter Z_VelocityTAS for TAS which I have been doing because I was finding the calculated value to be fair bit off the game parameter (which I have now fixed and is very close to game paramater now, see second method below).

The second method is to calculate from the IAS (I_VelocityIAS), converting through Pressure Altitude, i.e. adjusted from actual baro pressure to Standard Day Pressure and then to Density Altitude which adjusts it again taking into account actual Temperature vs Standard Day Temp.

Formulas are here:
http://williams.best.vwh.net/avform.htm#Altimetry

See "Relationship of pressure and indicated altitude:" for Pressure Altitude
and
"Relationship of pressure and density altitude:" for Density Altitude.

My full method is here:
http://forum.1cpublishing.eu/showpos...6&postcount=10

.....although I have tweaked the .cs file since then simply to correct the calculated TAS. I'll try to replace the zip file over the weekend. I'm currently working on a Bf109 set.

Beware of the indicated airspeed C#parameter Z_VelocityIAS as it seems to be wrong and far too close to Z_VelocityTAS even at altitude.

Quote:

Originally Posted by Kurfürst (Post 468680)

Geschwindigkeit Bf 109 V15 a
--------------------------------

Ü b e r s i c h t.

An Bf 109 V 15 a, der Mustermachine für die E-1-Serie, wurden die Geschwindigkeitsleistungen erflogen. Aus Zeitmengel konnten nicht die günstigen Rückstoßer und Ansaughutzen erflogen werden, sodaß evtl. noch Leistungssteigerungen möglich sind.

A n g a b e n

Maschine Bf 109 V 15 a D-ITPD W.-Nr. 1774

Motor DB 601 A W.-Nr. 140

Schraube 3 fl. VDM Verstellschraube 9-11081 W.-Nr.17459

Wasserkühler 1/4 geöffnet (Klappe in Straak) Wassertemperatur konstant = 90° bei +5° Außenlufttemperatur

Ölkühler Klappe geschlossen Öltemperatur 62/82°; Öldruck 3,2 kg/cm2 bei +5° Außenlufttemperatur

Ansaughutze Ausführung 1 Zeich.Nr. S-10361

Profil der Umlenksschaufeln ist so gewählt, daß Kanalquerschnitt fast konstant, bis auf eine kleine Verdickung der Vorderkante zur Erzielung einer runden Profilnase.

Rückstoßauspuff DB-Rückstoßer, von BFW angefertigt

Zustand des Flugwerkes

Oberfläche : serienmäßiger Anstrich, Motorhaube noch roh, Rückstoßer oben unverkleidet. 2 Flügel- und 2 Hauben-MG eingebaut. Eindrahtantenne. Fahrwehr eingezogen, Sporn außen.

"Surface: identical to serial production,
The engine cowling still rough, exhaust manifolds lacking top cover."
It seems that in serial production the aerodynamics will be a little better.