I'm sure someone will be able to provide a more definitive, mathematical
explination, but for what it's worth:
The altitude compensation takes into account your altitude when calculating
your speed. Without altitude compensation, your average speed would
significantly slow down every time you stop to thermal, and pick up
significantly when cruising - it would end up looking something like a
sine-wave if plotted.
An example of how altitude compensation works when flying is that it is
possible to increase your average speed, simply by thermalling. Lets say for
arguments sake you are doing 70kph on a weak 2-3 knot thermal day. If you
run into a 10 knot thermal, an altitude compensated speed will increase,
however a non-compensated altitude will decrease. Or if you are under a
cloud street doing 100kph and climbing at 5 knots, your instantaneous task
speed will be significantly more than 100kph.
Another example is if you leave a thermal at 10,000ft and cruise at VnE, you
would likely see that even though you're ground speed is very high, you will
likely see your average speed actually decrease. This is because XCSoar
recognises that even though you are traveling quickly, you are also losing
altitude disproportionally fast - you will need to thermal more often and
for a longer period in order to begin cruising again.
I'm not sure if you can disable altitude compensation, but i cant see why
anyone would want to. I've found that it has generally been accurate to
within a few KPH of the actual final achieved speed, and am sure it would be
much more accurate than a non-altitude compensated figure.
Luke
On 25 March 2011 02:35, Evan Ludeman <tangoei...@gmail.com> wrote:
> Can someone please provide or point to definitions of:
>
> Speed Task <achieved, average, instantaneous> as displayed in their
> respective info boxes and "compensated for altitude" ?
>
> Is there a way to get average speed without "altitude compensation", that
> is simply distance flown on task divided by elapsed time?
>
> Thanks...
>
> Evan
>
>
> ------------------------------------------------------------------------------
> Enable your software for Intel(R) Active Management Technology to meet the
> growing manageability and security demands of your customers. Businesses
> are taking advantage of Intel(R) vPro (TM) technology - will your software
> be a part of the solution? Download the Intel(R) Manageability Checker
> today! http://p.sf.net/sfu/intel-dev2devmar
> _______________________________________________
> Xcsoar-user mailing list
> Xcsoar-user@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/xcsoar-user
>
>
------------------------------------------------------------------------------
Enable your software for Intel(R) Active Management Technology to meet the
growing manageability and security demands of your customers. Businesses
are taking advantage of Intel(R) vPro (TM) technology - will your software
be a part of the solution? Download the Intel(R) Manageability Checker
today! http://p.sf.net/sfu/intel-dev2devmar
_______________________________________________
Xcsoar-user mailing list
Xcsoar-user@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/xcsoar-user
