What happened
On January 14, 2024, a Kubicek BB85Z balloon, registration N4961D, was involved in an accident near Eloy, Arizona. The flight was operating as a commercial sightseeing and skydiving operation. The flight began approximately one hour before sunrise, departing from a location about 18 miles west-northwest of the accident site.
After reaching an altitude of approximately 10,000 feet MSL, eight skydivers exited the basket in four separate groups. Following the departure of the final group of jumpers, the pilot pulled the red rapid deflation line 12 times. This action caused the envelope to deflate rapidly. The deflation caused the control lines to drop into the basket, which subsequently pinched the Red-White line within the flying cables.
Despite the pilot's attempts to relight the burner and use the Red-White line to close the vent, the envelope could not reinflate. The balloon continued to descend in a streamer-like configuration until the basket impacted the terrain. The accident resulted in 4 fatal injuries and 1 serious injury.
The investigation
Investigators reviewed onboard camera footage and multiple mobile phone videos from witnesses. The footage showed the pilot using the rapid deflation system at high altitudes. The examination of the N4961D revealed that the envelope was equipped with a Smart Vent system, which includes both a parachute valve mode and a rapid deflation mode. The rapid deflation mode is intended for use only when landing below 6.5 feet above ground level to prevent the basket from being dragged.
Post-accident examination of the basket, burner assembly, and envelope showed no mechanical anomalies that would have prevented normal operation. The investigation also noted that a swing rope, which is not a standard part of the balloon, was being used during the jumps.