Narrative:

Prior to takeoff within the austin arsa, the ATC was contacted for takeoff authority/authorized and to notify the ATC of departure time and takeoff location. I attempted to establish two-way communication as soon as practicable after takeoff, however, possibly due to the lo ambient temperature (36 degree) repeated calls to the ATC facility on the specified frequency failed to yield an ATC acknowledgement. Two other balloons taking off from the same launch site were able to establish radio contact. I was able to overhear their communication with the ATC just prior to radio failure. I ascended with the two other balloons to a minimum safe altitude, until I was able to land as soon as practicable. During the flight I notified the ground based balloon chase team by itinerant frequency FM radio to contact the ATC of my condition, altitude, heading and aircraft identify. The balloon chase team followed my instructions. I believe the problem could be avoided if the mfr of the aircraft radio were to supply battery rechargers which accounted for ni-cad charge memory and overcharge prevention. Otherwise an audible alarm may be used during power up to indicate the battery will sustain its charge for more than two hours.

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Original NASA ASRS Text

Title: NORDO TRAFFIC, A BALLOON MANNED, IN BALLOON ACTIVITY WITH TWO OTHERS WAS UNABLE TO ESTABLISH RADIO CONTACT WITH APCH CTLR.

Narrative: PRIOR TO TKOF WITHIN THE AUSTIN ARSA, THE ATC WAS CONTACTED FOR TKOF AUTH AND TO NOTIFY THE ATC OF DEP TIME AND TKOF LOCATION. I ATTEMPTED TO ESTABLISH TWO-WAY COM AS SOON AS PRACTICABLE AFTER TKOF, HOWEVER, POSSIBLY DUE TO THE LO AMBIENT TEMP (36 DEG) REPEATED CALLS TO THE ATC FAC ON THE SPECIFIED FREQ FAILED TO YIELD AN ATC ACKNOWLEDGEMENT. TWO OTHER BALLOONS TAKING OFF FROM THE SAME LAUNCH SITE WERE ABLE TO ESTABLISH RADIO CONTACT. I WAS ABLE TO OVERHEAR THEIR COM WITH THE ATC JUST PRIOR TO RADIO FAILURE. I ASCENDED WITH THE TWO OTHER BALLOONS TO A MINIMUM SAFE ALT, UNTIL I WAS ABLE TO LAND AS SOON AS PRACTICABLE. DURING THE FLT I NOTIFIED THE GND BASED BALLOON CHASE TEAM BY ITINERANT FREQ FM RADIO TO CONTACT THE ATC OF MY CONDITION, ALT, HDG AND ACFT IDENT. THE BALLOON CHASE TEAM FOLLOWED MY INSTRUCTIONS. I BELIEVE THE PROB COULD BE AVOIDED IF THE MFR OF THE ACFT RADIO WERE TO SUPPLY BATTERY RECHARGERS WHICH ACCOUNTED FOR NI-CAD CHARGE MEMORY AND OVERCHARGE PREVENTION. OTHERWISE AN AUDIBLE ALARM MAY BE USED DURING PWR UP TO INDICATE THE BATTERY WILL SUSTAIN ITS CHARGE FOR MORE THAN TWO HRS.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.