[LeArc] l Spirit of Knoxville appears to be on its own up there

[Mark A Garrett]

----- Forwarded Message ---- 
From: Dan Bowen < dbowen1 at mac.com > 



Looks like our Mark Caviezel ZP balloon is faring better than our GPS, according to the digipeaters it is coming through, it appears to be nearing the atlantic coast after 3 hours. This seems to correspond with winds near 30,000 ft, according to HYSPLIT.  If the balloon envelope alone can maintain a float until the next sunset, it is is possible that it may just be within VHF range of Newfoundland at sunset tomorrow evening.   

Having programmed the flight computer, the VHF will not ever turn off in this condition, it will continue to transmit the error message every 5 minutes until the GPS recovers or fully dies.  (Yes, it would have been nice to have the HF sending that too, but on that freq it could have been a pink slip here in the states) The flight computer can't tell what time it is nor where it is without valid GPS data.   


Not sure if it is a GPS failure or flight computer failure, we'll run some software simulations over the next few days and see what there is to be learned.   


73, 
Dan  
K2VOL 
UTARC 




On Jan 14, 2008 , at 11:49 PM, Mike Coffey wrote: 







It is unlikely that the HF transmitter will come on. It won't activate   
unless the GPS bad data condition is corrected. At this stage, the most   
probable outcome will be that the balloon will fly on, passing out of   
the US in the early hours of the morning, at which point its VHF   
transmitter will turn off. The HF transmitter will not activate if there   
is no GPS data, and at sunset on the 15th, the balloon will fail to   
ballast and descend to the ocean surface, bringing the flight to a   
close. Any stations who are able are requested to listen on our HF   
frequency in case the system does recover. 

73, 
Mike 
KJ4Z 

Greg Williams wrote: 
> 
> Its still transmitting, but bad GPS checksum. I dont know if thats only 
> on the 2m transmitter or if it will carry over to the 30m if/when it 
> gets out over the ocean. 
> 
> We'll know when it gets there. 
> 
> Greg 
> 
>   



Dan Bowen 


Program Manager 
UTARC Experimental High Altitude Balloon Program 
University of Tennessee Amateur Radio Club 
Knoxville, TN 

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