AKar wrote:I also understand that variation of air density as a function of temperature is effectively not modeled in FSX/P3D platform. Which I find curious, but haven't done any tests to check it out.
-Esa
Okay, I had to make a simple test - as simple as they come!
It turns out that my "understanding" was false. At least P3Dv4 indeed
does model density altitude effect to some extent.
Test setup:
Carenado Bonanza that ships with the P3Dv4. Default weather engine, no wind conditions, first set up at -25 °C sea level, dew point -30 °C; thereafter set up at +30 °C, dew point + 20 °C. Establish 1000 ft pressure altitude and 150 kIAS, and note the ground speed.
Reasoning:
Keeping constant IAS, that is
dynamic pressure, we effectively make ½
ÃÂv² = constant. Density
ÃÂ is a function of pressure (which we keep approximately constant) and of air temperature. Therefore, to balance the equation, should the temperature have effect on density
ÃÂ as it is supposed to, we must find higher GS/TAS
v when density
ÃÂ is smaller, i.e. the conditions are warmer.
Results:
1. Conditions -25 °C. Altitude 995 ft, indicated airspeed 150 knots.
True speed: 141 knots.
2. Conditions +30 °C. Altitude 1011 ft, indicated airspeed 150 knots.
True speed: 155 knots.
The results are roughly in line with the expected TAS values, proving that the density altitude has its proper effects. I must say I was somewhat surprised by the results.
I shall make more proper testing some time in conditions better suited for accurate results. But yet, the density altitude modeling is definitely there.
Edit: And it follows, obviously, that the turn radius is indeed affected by the temperature as well.
-Esa