Very nice. Please make sure it scales nicely, just by replacing the panel graphics and hotbutton list, for one axis and three axis modes. Third axis is autothrottle. Some notes, and additional functions.
> ButtonName - Description of function RATE - Turn rate, range of +/- 1 standard rate, does whatever is needed to keep the turn coordinator needle centered (kills you if the instrument fails). WING - Wing leveller, same as above with the rate forced to zero. Note that the pitch control functions need an internal aircraft-specific flag to specify whether that second axis moves the elevator or the pitch trim to achieve the desired control loop goal. It's important. > Of course this means that it'll also be possible to hold a pitch angle that > will stall the aircraft if the throttle is lowered enough. I'm not sure how > or if a real world autopilot deals with this type of error. That's a popular way to die. Tell autopilot to maintain level flight, reduce throttle (or acquire ice to increase drag). Aircraft slows down. (1) With elevator control, when force exceeds 20 pounds or so, the autopilot will drop out if the aircraft does not suddenly stall first. The aircraft will go into a steep nose down drive to recover trimmed airspeed, and will overshoot target airspeed by the same amount as it was undershot when the nose dropped. This will greatly exceed Va and may exceed Vne depending on the trimmed airspeed, making it very easy for the pilots to tear the wings off during the recovery attempt. (2) With trim control, the autopilot can fly the aircraft into the stall. When the pilots try to recover the stall, the trim is so far back that they may be unable to push against the forces hard enough to lower the nose and recover the stall. It is easy in this situation to forget to stay coordinated, while arguing with the autopilot, and end up in a spin. After enough accidents, each autopilot design is retrofitted to detect these situations and react gracefully. However, you have (a) no guarantee that the protection is actually working properly (b) no pilot records that it was actually upgraded on this specific unit _______________________________________________ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
