DEN89LA077 · Balloon Works AX8-24
Balloon Works AX8-24 · Accident: airframe, component or system failure during landing
Event
- NTSB case
- DEN89LA077
- Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
- Accident
- InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
- Completed
- API-reported fatalities
- 0 · all aircraft and ground
- Ground fatalities
- 0
- OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
- General aviation
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Visual Meteorological Cond
Balloon Works AX8-24
- Aircraft type
- Balloon Works AX8
- Category
- Balloon
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- N7127J
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From not recordedTo not recorded
- Aircraft age
- Not recorded
- Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
- Part 91: General Aviation
- Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
- Landing
- First occurrenceThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
- Airframe, component or system failure
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Substantial
Cause areas
- Balloon equipment, burner system › Failure, partial
- Fuel system, fuel shutoff › Frozen
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
THE COMMERCIAL PLT AND TWO FRIENDS WERE FLYING HIS BALLOON IN MOUNTAINOUS TERRAIN. DURING THE APPROACH TO LAND, THE PLT OPENED THE BURNER VALVE TO FLARE. THE VALVE STUCK OPEN AND THE PLT ATTEMPTED TO SHUT OFF FUEL AT THE PROPANE BOTTLE. THAT VALVE STUCK OPEN ALSO, AND THE BALLOON STARTED TO RISE. THE PLT REDUCED THE HEAT ENTERING THE ENVELOPE BY PULLING THE BURNER OUT OF THE THROAT AND POINTING IT OVERBOARD. THIS BALLOON WAS EQUIPPED WITH AN EMERGENCY 'BACK UP' BURNER SYSTEM. BY USING THE BACK UP BURNER, THE PLT MANEUVERED AND LANDED IN A WOODED AREA. THE PLT SAID THAT AFTER LANDING, HE WAS ABLE TO WORK THE STUCK VALVES UNTIL THEY CLOSED AND THE FUEL FLOW CEASED. A POST ACCIDENT INVESTIGATION REVEALED THAT CONDITIONS EXISTED CONDUCIVE TO ICE FORMING IN BOTH VALVES AND PREVENTING NORMAL OPERATION.
Probable cause
ICE FORMING IN THE FUEL TANK SHUT OFF VALVE, AND THE BURNER BLAST VALVE RESULTING IN A LOSS OF CONTROL DURING LANDING.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record DEN89LA077
- Event ID
- 20001213X27713
- Case number
- DEN89LA077
- Dataset
- historical-pre2008
- Source SHA-256
- 89e2df6d848e7ab3b42e7d7c7a03ff403303057a26ca04c95b3ea67201c3ce74
Source notes (4)
- Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
- Filled from the NTSB case API where the bulk record had no value: investigation status. Values present in the bulk record are kept.
- The date is the local date, which is the same as the UTC date the NTSB stores.
- API snapshot SHA-256: 41006af38ef2176adf0d75a6bf15e10671bac25ec3a1f218a0e5bc72b89a86d8; retrieved 2026-09-23T07:52:53.448Z.