Bug: Airspeed / Groundspeed

[graemeh]

I bought the F-15C in the current sale and it's an awesome model, and great fun to fly. However whilst practising landings with some wind turned on I've found an issue with the airspeed.

 

To demonstrate the issue clearly I've put 50m/s wind directly down the runway, track attached.

 

On the ground, the airspeed scale indicates 210 kts. (It should indicate about 100kts with the wind as set).

 

Accelerating down the runway and getting airborne the speed jumps from around 300 to 100. Landing again the speed jumps back again.

 

Then I turn around on the runway for a downwind takeoff. As I'm stopped pointing downwind the airspeed incorrectly indicates 200 knots, then as I accelerate it starts reducing towards 0, then lifting off it jumps to indicate 250 knots.

 

The groundspeed on the VSD indicates correctly throughout, but it seems that when airborne the IAS is actually showing groundspeed.

 

Obviously with more sensible winds this is less of an issue, but it's still a factor in the traffic pattern when turning downwind to final as the Pitch/Power/AoA seems to be correct but the Speed is unreliable.

 

Can anybody else confirm this bug?

F15 Airspeed Issue.trk

[graemeh]

I know 1.2.9 was not intended as a bug fix release for the F-15, but regardless this issue is still a problem in the current release.

 

Not an issue with the A-10C, and the F-15 flight dynamics seem to respond correctly so almost certainly an instrumentation issue. The flap auto-retraction speed is also affected by this wind setting though not in the same manner as the IAS.

[SDsc0rch]

yep.. this has annoyed me for quite some time