Hi,
the intensity and length of our discussion shows that people feel strongly
about the respective way of calculating AltRequired because they each "feel
safe" when they see the expected values according to their experience and their
routines. Therefore there is no right or wrong way of calculating /
displaying this, just different ones and I would be happy if XCSoar would
acknowledge both ways.
As for myself I prefer the way the LX, Cambridge etc. instruments calculate the
AltRequired to a single waypoint and I use XCSoar the same way Scott described,
but that is not the point - it would be best to find a solution and I have to
admit, I can't (yet) suggest a clean and elegant one. I can see John's point,
that making XCSoar configurable in that way might confuse newcomers, but I
can't think of an alternative.
To summarize things: The altreq. value shown on the glide bar and the labels is
computed differently since the new solver was introduced with vers. 6.1.x. I
believe. The last stable vers. using the old solver was vers. 6.0.10. The new
way seems to lead to fast dropping values of altreq. shown in the glide bar
when wrongly circling in a lift to weak to compensate for the drift while
circling, which is scientifically correct, but is different from hardwired
computers (e.g. Cambridge, LX etc.).
Now getting back to a possible solution. Please correct me if I am wrong, the
glide bar is intended to show the total altreq. for the complete task and
therefore helpful when in competition. The altreq. displayed next to the
labels Max Kellermann explained recently to me are calculated differently by
separate solvers considering flight around terrain, airspace, safety MC,
wind etc. (vers. 6.1.x and newer). Therefore one experiences slight difference
in the altreq. values displayed in the glide bar and on the labels (when above
glidepath). If XCSoars already uses different methods for glide bar and
labels, couldn't we make the glide bar configurable for a) task mode (as
implemented in 6.2.3) and b) abort mode, meaning a task to a single (final)
waypoint, showing the same value as the label shows and using the "old"
method. So if below glide path the label would show "not reachable" while the
glide bar would show the e.g. -500feet below
glide path. How one gets above glide path is up to the pilot and his decision
whether to circle, chance an outlanding or hope for lift during straight flight
etc.
Any thoughts for solutions? And many thanks to the developers for their hard
work and for following and allowing this discussion.
Cheers,
Sascha
________________________________
Von: David Lawley <davidlaw...@hotmail.com>
An: tangoei...@gmail.com; m...@duempel.org
Cc: xcsoar-user@lists.sourceforge.net
Gesendet: 2:10 Dienstag, 22.November 2011
Betreff: Re: [Xcsoar-user] XCSoar 6.2.3 released
My only comment is i was perfectly happy with the behaviour of final glide in
5.2, everytime it predicted the final glides perfectly.
Storm in a teacup methinks!
Dave
> From: tangoei...@gmail.com
> Date: Mon, 21 Nov 2011 19:11:09 -0500
> To: m...@duempel.org
> CC: xcsoar-user@lists.sourceforge.net
> Subject: Re: [Xcsoar-user] XCSoar 6.2.3 released
>
>
> On Nov 21, 2011, at 5:48 PM, Max Kellermann wrote:
>
> > On 2011/11/21 23:40, Evan Ludeman <tangoei...@gmail.com> wrote:
> >> Sorry John, no sale. We need height relative to glide slope at a pilot
> >> selectable Mc setting for final glide. If that's being eliminated in
> >> preference wind dependent height of climb required, that's a poor
> >> choice.
> >
> > What XCSoar shows is not the height relative to the glide slope.
> >
> > What XCSoar shows is how much you need to climb to reach your goal.
> >
> > The height relative to the glide slope is a theoretical number that is
> > of no practical use for a glider, even if it might be appealing to
> > calculate it, and even if it gives you the illusion that it is useful.
> >
> > Max
> >
>
> I disagree, rather strongly.
>
> 30 miles out on final glide, 500' below glide slope, I am not looking for a
> thermal to center and circle in, I am looking for enroute lift to get up to a
> comfortable final glide. The height below glide slope is preferable to height
> required to climb (in circling). I'm rather astonished to find out about how
> XCS is doing these calculations, I didn't know this but in retrospect it does
> explain (perhaps) some of the discrepancies I have noted between XCS and my
> C-302/303. As previously noted, I always go with the 302/303 as primary
> reference for final glide.
>
> This whole conversation completely astonishes me. I never suspected that
> anyone doubted the utility of height relative to glide slope for final glide.
>
> It appears to me that there are some who are out to put "all the brains in
> the box". That's an interesting intellectual and software engineering
> challenge to be sure, but it's not what I am interested in. I am solely
> interested in aids to my situational awareness. I find height relative to
> glide slope to be such an aid. Height required to climb given an assumed
> thermal strength... not so much.
>
> -Evan
> ------------------------------------------------------------------------------
> 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
------------------------------------------------------------------------------
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
