You are right with your second point about the two airfields, but I think we should let the pilot figure this out. I guess I would have to agree that the time spent circling shouldn't be a factor. AFAIK no other software does it that way... As I mentioned earlier, we could make it configurable but I don't think that's really useful.
Turbo 2011/11/21 John Wharington <jwharing...@gmail.com>: > We will have to agree to disagree on that. > Arrival altitude should indeed consider circling, and you should set a > reasonable MC value, if you are able to climb. If you don't expect to > be able to climb, then set MC=0. > > If conditions are such that climbing in weak lift makes an upwind > landing point effectively unreachable, this should be shown. If > downwind drift due to circling was not taken into account, then > two airfields just beyond pure glide range would look similarly > attractive even though in actuality, the downwind one will be much > more reachable at a low climb rate. > > On Tue, Nov 22, 2011 at 3:09 AM, Ramy Yanetz <ryan...@yahoo.com> wrote: >> Arrival altitude should NEVER consider circling! I never heard of such >> theory. Arrival altitude should only consider polar, degradation, wind and >> MC, although it would be fine without considering MC at all. But trying to >> guess your climb and your drift while climbing is completely wrong. We are >> not trying to predict the future, we are trying to tell the pilot if he can >> safely reach an airport or how much he needs to climb. >> >> Ramy >> >> On Nov 21, 2011, at 5:43 PM, Tobias Bieniek <tobias.bien...@gmx.de> wrote: >> >>> John, I think this is inconsistent behaviour... either if you can't >>> climb you shouldn't see the pure glide value, or if you have a MC >>> above 0 you shouldn't consider the wind effect while circling. Maybe >>> for internal calculations we should supply both values and let the >>> user decide what he wants to see. >>> >>> Turbo >>> >>> >>> >>> 2011/11/21 John Wharington <jwharing...@gmail.com>: >>>> This is not a bug. >>>> >>>> At MC=0, you cannot climb, so the value reported (-500 feet) indicates >>>> you magically need to gain 500 feet in order to glide at MC=0. >>>> >>>> At MC=0.5, you are telling the computer you can climb, and with that >>>> headwind and a slow climb rate (0.5), you need to climb a lot more. >>>> In this case, the 500 feet isnt obtained magically, and so the height >>>> required takes the downwind drift from circling into account. >>>> >>>> On Tue, Nov 22, 2011 at 1:34 AM, Ramy Yanetz <ryan...@yahoo.com> wrote: >>>>> Arrival altitude was at MC =0 was something like -500 feet (500 feet >>>>> below glide) which was correct. However, With MC=0.5 it was -6000 feet!!! >>>>> This is obviously a bug since the slight increase in MC will never result >>>>> in 5000 feet loss. >>>> >>>> ------------------------------------------------------------------------------ >>>> All the data continuously generated in your IT infrastructure >>>> contains a definitive record of customers, application performance, >>>> security threats, fraudulent activity, and more. Splunk takes this >>>> data and makes sense of it. IT sense. And common sense. >>>> http://p.sf.net/sfu/splunk-novd2d >>>> _______________________________________________ >>>> Xcsoar-user mailing list >>>> Xcsoar-user@lists.sourceforge.net >>>> https://lists.sourceforge.net/lists/listinfo/xcsoar-user >>>> >> > ------------------------------------------------------------------------------ All the data continuously generated in your IT infrastructure contains a definitive record of customers, application performance, security threats, fraudulent activity, and more. Splunk takes this data and makes sense of it. IT sense. And common sense. http://p.sf.net/sfu/splunk-novd2d _______________________________________________ Xcsoar-user mailing list Xcsoar-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/xcsoar-user
