I've been revisiting FSX Gold and embarked recently on X-plane10, while still being a true fanatic for FLIGHT (still the best overall GA "flying" experience over any simulator I have used so far...).

 

I tried to find out how propwash effects are modeled on the three simulators. For the tests I picked the default Cub and p-51 (Reno Air Races model in FSX Gold) in FSX, the Carbon Cub Deluxe and the Red Tail p-51 in FLIGHT and a few very nice WW1 freeware aircraft in X-Plane 10 b8.

 

Here are my findings ;-)

 

- FSX and FLIGHT: You have propwash effects on the horizontal stab and elevator, thus allowing you to lift the tail from the ground, and even try to maintain it up without prop strike, but you need a powerful plane. The default Reno Air Races p51 in Acceleration does it. For other taildraggers you need some wind component from 12 o'clock to help. In MS FLIGHT you allways need a wind component directly from ahead (12 o'clock).

 

Also, there are effects of propwash on the vertical stab/rudder, but if you wave the rudder side to side, the aircraft will stand still in FSX (and in FLIGHT too) unless there is some wind component from 12 o'clock.

 

- X-plane10.10b8: You have propwash effects, both on horizontal and vertical tail surfaces, but on most airplanes waving the rudder doesn't have noticeable effec, while on others the effect is clearly visible. You do not need a wind component from 12 o'clock in X-Plane. Also, maintaining the tail in the air without prop strike is a little bit more difficult in X-Plane

 

Conclusion: All of the three sims do it, but I prefer X-Plane's results, with no wind component being required for the effects to become effective on the vertical surfaces, provided you have a powerful engine...

Its in the air files, but not really utilized.

Oh, I know, and some do use it as far as the core in fs9/fsx allows, even so not as good as in X-Plane :-)

I'm not an Xplane user, so I don't have a useful opinion on it. For both FSX and Xplane, the airfile itself is very important and variable. I think a good comparison would be to look at one aircraft from a single dev that’s available in both. Carenado comes to mind. And even so, we'd still have to assume the author's effort and expertise was equal in both. Most of all, I’d love to hear from a designer that’s accomplished in both.

 

The effects of propwash on the rudder do work in FSX. The deficiency could be the airfiles you happened to look at. For aircraft with castoring wheels this effect is particularly important. I have tuned this effect myself. In the process I start with an exaggerated effect and then tune it down. An exaggerated effect is actually a lot more fun to maneuver ;) But (in the RV) at very-very slow speeds it's more about differential braking, and the aerodynamic effect is a bit more restrained...but it's there :)

And I am sure you did a great job using it because L.Adamson uses your RV as the best example of an RV for a flightsim :-)

 

I know about the absence of the record or misuse in some cases. Spent months around it with Ron Freimuth, before he passed away in 2006, when dealing with an airfile for a Stemme motor glider :-)

 

I would love to see developers like you, Rob Young, Bernt Stolle, A2A, etc... starting project in the X-Plane platform. I am sure we would come up with an even more rich simulation...