Ticket #1803 (closed enhancement: duplicate)
Covering plane performance degradation
|Reported by:||DGFlija||Owned by:|
|Keywords:||polar curve degradation||Cc:|
It is a well known fact that a glider does not always reach its factory announced performance values. It is also a well known fact that unexperienced pilots cannot yet live up to use a plane at its top notch performance, even if the plane is perfectly sealed.
The most common way to take care of these issues is the way I learned to deal with them 45 years ago with a Ka6 and I still do it that way with an ASH and a DG800 : I start the final glide with excess altitude.
In my experience the extra altitude needed is more or less relative to the time to go, not the distance to go. Very surprising ;-). So, why not make that a feature : Have a configurable and persistent percentage value by which the required altitude to reach a goal is increased - on top of the configurable safety altitude for the landing pattern.
The precentage should be chosen individually by the pilot so that it works for him with small MacCready? settings (<= 0.5). When using higher MacCready? settings there is even more safety in the speed already. So there is no compensation required for high MacCready? speeds.
Then, I think, "bug degradation" and "polar curve" and "MacCready? setting", which have been discussed as means to handle bad performance, can be left alone for their proper purpose and set to the same values, the 302 or the VEGA or the Butterfly are set to.
- Version changed from 6.3 to 6.2.5
- Milestone changed from XCSoar 6.2 to XCSoar 6.3
- Status changed from new to closed
- Version changed from 6.2.5 to 6.3
- Resolution set to duplicate
- Milestone changed from XCSoar 6.3 to XCSoar 6.4