Narrative:

150 balloons were participating in a balloon race. I was flying in the 'hare and hound' competition where the goal is to throw a bean bag as close as possible to either of 2 X's placed on the ground by the 2 'hare' balloons. I was in level flight about 100 ft AGL, about 1/4 mi from the target, traveling at about 4 mph, when I felt a rocking motion to 1 side. I looked at my 2 passenger to see if they had caused it (although it was a larger motion than I had ever experienced) and saw that they had not moved. Then I looked up and saw the shadow of another basket rising from the top of my balloon. The other balloon had descended into the top of my envelope and rebounded off. Luckily, there was no damage to the fabric. A basket-to-envelope collision can easily rip the envelope, causing a rapid, possibly uncontrollable descent/crash. The cause of this collision was undoubtedly 'target fix,' wherein a pilot becomes so involved with approaching the target that he does not pay attention to other nearby aircraft. Another pilot in a nearby balloon witnessed the collision and said the basket descended into my envelope up to its top bolster (about 3-4 ft). Had I been climbing at the time, the resulting collision would have been much worse. Although an event such as this has a high density of balloons, there is sufficient space to safely operate several times this many balloons. It is simply necessary for everyone to pay attention to nearby balloons. Callback conversation with reporter revealed the following information: the reporter reported this incident to the event organizers with the intruding pilot's name. He did not report this to the FAA and has not heard anything further either from the event organizers or the FAA. The reporter was upset that the intruding pilot did not come to him to apologize.

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Original NASA ASRS Text

Title: HOT AIR BALLOON (Y) DSNDED INTO THE TOP OF HOT AIR BALLOON (X). THERE WERE NO DAMAGES OR INJURIES. SPECIAL INTEREST ACTIVITY BALLOON COMPETITION. NMAC.

Narrative: 150 BALLOONS WERE PARTICIPATING IN A BALLOON RACE. I WAS FLYING IN THE 'HARE AND HOUND' COMPETITION WHERE THE GOAL IS TO THROW A BEAN BAG AS CLOSE AS POSSIBLE TO EITHER OF 2 X'S PLACED ON THE GND BY THE 2 'HARE' BALLOONS. I WAS IN LEVEL FLT ABOUT 100 FT AGL, ABOUT 1/4 MI FROM THE TARGET, TRAVELING AT ABOUT 4 MPH, WHEN I FELT A ROCKING MOTION TO 1 SIDE. I LOOKED AT MY 2 PAX TO SEE IF THEY HAD CAUSED IT (ALTHOUGH IT WAS A LARGER MOTION THAN I HAD EVER EXPERIENCED) AND SAW THAT THEY HAD NOT MOVED. THEN I LOOKED UP AND SAW THE SHADOW OF ANOTHER BASKET RISING FROM THE TOP OF MY BALLOON. THE OTHER BALLOON HAD DSNDED INTO THE TOP OF MY ENVELOPE AND REBOUNDED OFF. LUCKILY, THERE WAS NO DAMAGE TO THE FABRIC. A BASKET-TO-ENVELOPE COLLISION CAN EASILY RIP THE ENVELOPE, CAUSING A RAPID, POSSIBLY UNCTLABLE DSCNT/CRASH. THE CAUSE OF THIS COLLISION WAS UNDOUBTEDLY 'TARGET FIX,' WHEREIN A PLT BECOMES SO INVOLVED WITH APCHING THE TARGET THAT HE DOES NOT PAY ATTN TO OTHER NEARBY ACFT. ANOTHER PLT IN A NEARBY BALLOON WITNESSED THE COLLISION AND SAID THE BASKET DSNDED INTO MY ENVELOPE UP TO ITS TOP BOLSTER (ABOUT 3-4 FT). HAD I BEEN CLBING AT THE TIME, THE RESULTING COLLISION WOULD HAVE BEEN MUCH WORSE. ALTHOUGH AN EVENT SUCH AS THIS HAS A HIGH DENSITY OF BALLOONS, THERE IS SUFFICIENT SPACE TO SAFELY OPERATE SEVERAL TIMES THIS MANY BALLOONS. IT IS SIMPLY NECESSARY FOR EVERYONE TO PAY ATTN TO NEARBY BALLOONS. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR RPTED THIS INCIDENT TO THE EVENT ORGANIZERS WITH THE INTRUDING PLT'S NAME. HE DID NOT RPT THIS TO THE FAA AND HAS NOT HEARD ANYTHING FURTHER EITHER FROM THE EVENT ORGANIZERS OR THE FAA. THE RPTR WAS UPSET THAT THE INTRUDING PLT DID NOT COME TO HIM TO APOLOGIZE.

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.