Accident Overview
On November 9, 2013, about 0800 Pacific standard time, a Firefly Balloons, Inc., Firefly 10 (registration N1623L) experienced a fire after landing near Temecula, California. The balloon was operated by D&D Hot Air Ballooning under 14 CFR Part 91. The airline transport pilot (commercial lighter-than-air balloon pilot) and four passengers sustained serious injuries; five passengers were not injured. The balloon was not damaged during the accident sequence. The local sight-seeing flight had departed Temecula about 0700. Visual meteorological conditions prevailed, and no flight plan had been filed.
Pilot Statement
The pilot provided a written statement. He stated that after landing, he shut off the pilot light of one burner and took the burner down from the flight position to put it in the storage bag attached to the side of the basket. While putting the burner in the bag, he bumped the blast valve, causing propane to come out of the burner. The propane ignited, but he did not know what the ignition source was.
Burner Examination
A Federal Aviation Administration (FAA) inspector and the National Transportation Safety Board investigator-in-charge supervised examination of the two burners. For Serial Number 836, the hoses were about 9 years old; the main burner hose and pilot valve hose had minor cracks but were not leaking. Using a soapy spray solution, a minor leak was found at the fitting of the Fire 2 hose, but it was not considered dangerous. Black residue, which propane leaves when leaking, was present. For Serial Number 856, the main burner hose fitting was loose and leaking slightly; the pilot valve hose and Fire 2 hose were in good condition with no leaks. Both burners were individually hooked up to a test unit; the hoses displayed no anomalies, and functional tests were completed with no anomalies noted, and shutdown was unremarkable.
Flight Manual Instructions
Section 3.6 of the flight manual instructs that just prior to touchdown, the pilot should make sure the trigger valve (and/or fire 2 valve) is firmly closed and close the pilot light safety shutoff. After landing, the pilot should bleed all fuel lines, ensuring all valves are firmly closed, checking for safety, and then opening the trigger valve and pilot light safety shutoff. Section 3.7.2 states that before transport, the pilot should dismount the burner from the burner supports and adjust fuel losses to avoid contact with tanks or protrusion. The FAA inspector interviewed the pilot and noted that the pilot did not follow the instructions in the flight manual: the pilot did not shut off the appropriate valves or bleed the system of gas after the pilot light was extinguished.