From: David M. <da...@me...> - 2001-07-14 12:49:59
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Wolfram Kuss writes: > >> The FDMs already use the wind information, and Jon has modified JSBSim > >> to respond realistically to sudden changes. > > Really!?! I didn't know that. In that case, at least two of us > (Christian and me) gave out wrong info at the LinuxTag. We told people > that the wind was just being added to the airplane velocity, which > means constant wind works (for example screwing up your navigation > :-)) while non-constant wind is not modelled correctly. > > If this really works, very cool! Here's how to try it out. Start FlightGear with telnet support and the JSBSim C172: fgfs --props=socket,bi,5,localhost,5500,tcp --fdm=jsb --aircraft=c172 In a separate window (or from another machine), telnet into FlightGear: telnet localhost 5500 then change to the environment subtree and take a peek: /> cd environment /environment[0]> ls clouds/ visibility-m = '10000.000000' (double) wind-north-fps = '0.000000' (double) wind-east-fps = '0.000000' (double) wind-down-fps = '0.000000' (double) magnetic-variation-deg = '-14.131638' (double) magnetic-dip-deg = '71.772292' (double) Take off and climb to altitude, then try playing with the wind components, i.e. set wind-east-fps 20 You'll notice that the airspeed now changes. If you add a strong headwind, the airspeed will initially rise and then more slowly fall back to normal; if you add a strong tailwind, the airspeed will initially drop (you might even stall) and then gradually rise back to normal. > You get the wind (inclusive up/downdrafts) from Christian's weather > module, don't you? I am not sure what is involved to get the weather > module to handle thermals. Christian's weather module does really do anything yet. I don't know how much work is involved in getting it running. All the best, David -- David Megginson da...@me... |