Narrative:

The incident took place when balloon #2 envelope made contact with balloon #1 basket shortly after passing the target area of the race. Prior to the incident, both balloon #2 and #1 were approaching the target area and were several hundred ft apart. Balloon #2 dropped or descended immediately after passing a forest of high trees. According to the pilot on our conversation after the incident, the rotor effect of the winds drove him down toward the ground and he utilized both burners on the balloon to arrest the descent. He apparently overburned, put too much heat into the balloon, and thus caused the balloon to ascend rapidly. Balloon #2 also lost almost all of its previous forward momentum due to the effect of the trees. Balloon #1 approaching on the same path as balloon #2 did not drop below the tree line and therefore did not slow down, thus causing balloon #1 to overtake balloon #2 who had considerably stopped its forward momentum. This in addition to the fact that the pilot in balloon #1 did not know as he approached balloon #2 that the pilot had overburned and that balloon #2 would shortly be rapidly rising. As balloon #1 started overtaking balloon #2 he immediately put heat into his balloon and started an ascent. The pilot of balloon #1 stopped burning long enough to shout to balloon #2 that he was getting close and would soon be overhead. At this point pilot #1 realized that balloon #2 was rapidly ascending and thus pilot #1 continued to heat his balloon until contact between the basket and envelope was inevitable. The envelope of balloon #2 touched the basket on balloon #1 and as they separated, the envelope on balloon #2 tore. The pilots of both balloons safely landed shortly thereafter. The fact that balloon #1 only had 1 burner as compared to balloon #2's double burners contributed to the slower response time and ascension speed of balloon #1. If balloon #1 had known sooner that a balloon was overhead he may have been able to vent and slow his ascent. Supplemental information from acn 445641: during the morning flight after descending into target area, I dropped marker and was climbing out of area at approximately 300 FPM. I ascended into another balloon that was unable to give way due to possibly faster winds above. My aircraft sustained a tear in the fabric at the top of balloon after contacting basket of balloon above. I was able to fly to an appropriate landing location approximately 1/4 mi downwind without incident. There were no injuries to any persons and the only physical damage that was sustained was to my balloon. My equipment (balloon) is currently being repaired at an approved repair facility.

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Original NASA ASRS Text

Title: HOT AIR BALLOONS COLLIDE 300 FT AGL DURING BALLOON MEET. BALLOON Y CLBED UP INTO BALLOON X CAUSING TEAR IN BALLOON Y CANOPY WHEN IT PULLED AWAY FROM BALLOON X'S BASKET. BOTH BALLOONS LANDED SAFELY.

Narrative: THE INCIDENT TOOK PLACE WHEN BALLOON #2 ENVELOPE MADE CONTACT WITH BALLOON #1 BASKET SHORTLY AFTER PASSING THE TARGET AREA OF THE RACE. PRIOR TO THE INCIDENT, BOTH BALLOON #2 AND #1 WERE APCHING THE TARGET AREA AND WERE SEVERAL HUNDRED FT APART. BALLOON #2 DROPPED OR DSNDED IMMEDIATELY AFTER PASSING A FOREST OF HIGH TREES. ACCORDING TO THE PLT ON OUR CONVERSATION AFTER THE INCIDENT, THE ROTOR EFFECT OF THE WINDS DROVE HIM DOWN TOWARD THE GND AND HE UTILIZED BOTH BURNERS ON THE BALLOON TO ARREST THE DSCNT. HE APPARENTLY OVERBURNED, PUT TOO MUCH HEAT INTO THE BALLOON, AND THUS CAUSED THE BALLOON TO ASCEND RAPIDLY. BALLOON #2 ALSO LOST ALMOST ALL OF ITS PREVIOUS FORWARD MOMENTUM DUE TO THE EFFECT OF THE TREES. BALLOON #1 APCHING ON THE SAME PATH AS BALLOON #2 DID NOT DROP BELOW THE TREE LINE AND THEREFORE DID NOT SLOW DOWN, THUS CAUSING BALLOON #1 TO OVERTAKE BALLOON #2 WHO HAD CONSIDERABLY STOPPED ITS FORWARD MOMENTUM. THIS IN ADDITION TO THE FACT THAT THE PLT IN BALLOON #1 DID NOT KNOW AS HE APCHED BALLOON #2 THAT THE PLT HAD OVERBURNED AND THAT BALLOON #2 WOULD SHORTLY BE RAPIDLY RISING. AS BALLOON #1 STARTED OVERTAKING BALLOON #2 HE IMMEDIATELY PUT HEAT INTO HIS BALLOON AND STARTED AN ASCENT. THE PLT OF BALLOON #1 STOPPED BURNING LONG ENOUGH TO SHOUT TO BALLOON #2 THAT HE WAS GETTING CLOSE AND WOULD SOON BE OVERHEAD. AT THIS POINT PLT #1 REALIZED THAT BALLOON #2 WAS RAPIDLY ASCENDING AND THUS PLT #1 CONTINUED TO HEAT HIS BALLOON UNTIL CONTACT BTWN THE BASKET AND ENVELOPE WAS INEVITABLE. THE ENVELOPE OF BALLOON #2 TOUCHED THE BASKET ON BALLOON #1 AND AS THEY SEPARATED, THE ENVELOPE ON BALLOON #2 TORE. THE PLTS OF BOTH BALLOONS SAFELY LANDED SHORTLY THEREAFTER. THE FACT THAT BALLOON #1 ONLY HAD 1 BURNER AS COMPARED TO BALLOON #2'S DOUBLE BURNERS CONTRIBUTED TO THE SLOWER RESPONSE TIME AND ASCENSION SPD OF BALLOON #1. IF BALLOON #1 HAD KNOWN SOONER THAT A BALLOON WAS OVERHEAD HE MAY HAVE BEEN ABLE TO VENT AND SLOW HIS ASCENT. SUPPLEMENTAL INFO FROM ACN 445641: DURING THE MORNING FLT AFTER DSNDING INTO TARGET AREA, I DROPPED MARKER AND WAS CLBING OUT OF AREA AT APPROX 300 FPM. I ASCENDED INTO ANOTHER BALLOON THAT WAS UNABLE TO GIVE WAY DUE TO POSSIBLY FASTER WINDS ABOVE. MY ACFT SUSTAINED A TEAR IN THE FABRIC AT THE TOP OF BALLOON AFTER CONTACTING BASKET OF BALLOON ABOVE. I WAS ABLE TO FLY TO AN APPROPRIATE LNDG LOCATION APPROX 1/4 MI DOWNWIND WITHOUT INCIDENT. THERE WERE NO INJURIES TO ANY PERSONS AND THE ONLY PHYSICAL DAMAGE THAT WAS SUSTAINED WAS TO MY BALLOON. MY EQUIP (BALLOON) IS CURRENTLY BEING REPAIRED AT AN APPROVED REPAIR FACILITY.

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.