XCSoar wind calculation

On Thu, 01 Oct 2009 14:20:57 +0000, PCool wrote:

The fact that wind is not calculated means that either you are not
thermalling with a constant bank angle, or that there is a very strong
wind, or - most probably - that your gps is not passing correct
positions to the software due to an antenna problem (weak signal
reception, sufficient with no banking, but not sufficient while
thermalling with high bank angles). Hp310-314 has this problem
for instance.

Not quite!

The help screen (once I read it) says in no uncertain terms that zigzag
wind calculation doesn't work if the only input is GPS.

My PNA was certainly not producing sensible cruise calculated wind and,
as it has a GPS as its only sensor, 'Both' must be incorrect since it
uses 'Circle' while climbing and 'zigzag' in cruise. So, I've set the
wind calculation to 'Circle' like the help page suggested.

I'll report back once I've flown in 'Circle' mode. Should have been
today, but a balky online bank and a misread forecast put paid to that.
Rats!


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |

On Oct 1, 7:38*pm, Martin Gregorie
wrote:
On Thu, 01 Oct 2009 14:20:57 +0000, PCool wrote:
The fact that wind is not calculated means that either you are not
thermalling with a constant bank angle, or that there is a very strong
wind, or - most probably - that your gps is not passing correct
positions to the software due to an antenna problem (weak signal
reception, sufficient with no banking, but not sufficient while
thermalling with high bank angles). Hp310-314 has this problem
for instance.

Not quite!

The help screen (once I read it) says in no uncertain terms that zigzag
wind calculation doesn't work if the only input is GPS.

My PNA was certainly not producing sensible cruise calculated wind and,
as it has a GPS as its only sensor, 'Both' must be incorrect since it
uses 'Circle' while climbing and 'zigzag' in cruise. So, I've set the
wind calculation to 'Circle' like the help page suggested.

I'll report back once I've flown in 'Circle' mode. Should have been
today, but a balky online bank and a misread forecast put paid to that.
Rats!

--
martin@ * | Martin Gregorie
gregorie. | Essex, UK
org * * * |

Mine is and has always been set to "circling". In the same plane it
all worked great on another PDA with the same settings. I will try to
reposition the GPS dongle next time out but note that when I examine
my flights in See You, the GPS appears to work fine with no brownouts/
missing data points. FWIW, the logger time steps are set to 5 seconds
cruise, 1 second thermalling.

/Adam