Narrative:

My hot air balloon was being prepared for takeoff at a local small airport. The system was inflated and loaded, and tied off. I checked for liftoff buoyancy, disengaged the tie-off and began the ascent. Almost immediately the balloon leveled out and moved horizontally about 45 degrees from the original path and quickly reached another aircraft (fixed wing bonanza) which was parked and tied down. My basket struck the parked bonanza. This event was avoidable. There should have been a much greater space allowed for takeoff. The rate of climb should have been increased (higher envelope for load). My judgement of these factors was simply incorrect/miscalculated.

Google
 

Original NASA ASRS Text

Title: HOT AIR BALLOON PLT HIT A PARKED AND TIED DOWN ACFT WHILE ATTEMPTING TKOF.

Narrative: MY HOT AIR BALLOON WAS BEING PREPARED FOR TKOF AT A LCL SMALL ARPT. THE SYS WAS INFLATED AND LOADED, AND TIED OFF. I CHKED FOR LIFTOFF BUOYANCY, DISENGAGED THE TIE-OFF AND BEGAN THE ASCENT. ALMOST IMMEDIATELY THE BALLOON LEVELED OUT AND MOVED HORIZLY ABOUT 45 DEGS FROM THE ORIGINAL PATH AND QUICKLY REACHED ANOTHER ACFT (FIXED WING BONANZA) WHICH WAS PARKED AND TIED DOWN. MY BASKET STRUCK THE PARKED BONANZA. THIS EVENT WAS AVOIDABLE. THERE SHOULD HAVE BEEN A MUCH GREATER SPACE ALLOWED FOR TKOF. THE RATE OF CLB SHOULD HAVE BEEN INCREASED (HIGHER ENVELOPE FOR LOAD). MY JUDGEMENT OF THESE FACTORS WAS SIMPLY INCORRECT/MISCALCULATED.

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.