Balloon Works FIREFLY 8 accident near Napa, California, August 7, 1990
On August 7, 1990 at about 2:46 pm local time, a Balloon Works FIREFLY 8, registered N9023Z, was involved in an accident near Napa, California. It was a flight of an unrecorded kind under general aviation rules (Part 91). 1 person was seriously injured and 1 person had minor injuries; 5 others were unhurt. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
THE FLIGHT'S ENCOUNTER WITH A PROBABLE MICROBURST WEATHER PHENOMENA WITH DOWN DRAFTS AND WINDS BEYOND THE PERFORMANCE CAPABILITY OF THE BALLOON.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- August 7, 1990 · about 2:46 pm local time
- Place
- Napa, California · map
- Type
- Accident
- Injuries
- 1 person was seriously injured and 1 person had minor injuries; 5 others were unhurt.
- Weather
- visual conditions (good weather)
- Aircraft
- Balloon Works FIREFLY 8 · all FIREFLY 8s on the register
- Registration
- N9023Z · no longer on the register · serial F8-350
- Damage
- Not recorded
- Flight
- Flight of an unrecorded kind · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
SEVENTEEN BALLOONS LAUNCHED FROM VARIOUS LOCATIONS AROUND THE NAPA VALLEY FOR LOCAL SIGHTSEEING FLIGHTS. STATEMENTS FROM PILOTS, PASSENGERS AND GROUND WITNESSES SAID THAT WHILE THE BALLOONS WERE IN NORMAL DRIFTING FLIGHT A MICROBURST LIKE CONDITION SUDDENLY OCCURRED WHICH AFFECTED ALL OF THE BALLOONS. THE WEATHER PHENOMONA ENCOUNTERED INCLUDED STRONG GUSTING SURFACE AND ALOFT WINDS IN ADDITION TO SEVERE DOWN DRAFTS. THE BALLOONS WERE RAPIDLY FORCED TOWARD THE GROUND AS THEIR GROUND SPEED INCREASED RADICALLY. THE PILOTS OF SEVERAL BALLOONS REPORTED THAT THE SHAPES OF THEIR BALLOON ENVELOPES WERE SEVERELY DISTORTED BY THE SUDDEN MOVEMENT OF THE AIRMASS. EIGHT OF THE 17 BALLOONS ATTEMPTED FORCED LANDINGS. FOUR OF THE BALLOONS SUCCESSFULLY LANDED. THE OTHER FOUR BALLOONS COLLIDED WITH OBSTRUCTIONS AND THE GROUND DURING THE ATTEMPTED LANDINGS. AT THE TIME OF THE INCIDENT, A LARGE THUNDERSTORM WAS REPORTED 30 MILES TO THE NORTH.
The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.
The factual record from the NTSB's investigation tables, in plain English
Pilot
- Certificate: commercial pilot
- Ratings: rotorcraft: balloon
- Flight time: 210 hours in all
- Medical certificate: None
- Seat: unk
The aircraft
- Last inspection: inspection type not recorded; 0 hours since
- Maximum gross weight: 2,450 lb
- Landing gear: retractable
- Engine: (type not recorded); 0 hours total
The flight
- Departed from: NONE at 2:00 pm
- Destination: NONE
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 180° at 20 knots, gusting 30
- Visibility: 30 statute miles
- Sky: overcast at 30,000 ft; clear
- Temperature: 70°F (21°C), dew point 57°F (14°C)
- Altimeter: 29.00 inHg
- Observation at 7:45 am from APC
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 | |||
| Passengers | 1 | 1 | 4 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
The docket, the folder of records gathered during an investigation (maintenance records, photographs, witness statements, examinations), has not been read from the NTSB for this case yet; the list appears here once it has. Open the docket at the NTSB.
Other NTSB records under N9023Z the same tail number, which may have belonged to a different aircraft at the time
Everything on this page comes from the NTSB's public records. The narrative, probable cause and findings are the NTSB's own words; the coded tables behind the report are written out in plain English, with pilots' ages, home towns and medical details left out. The documents and photographs are the NTSB's docket, shown as the NTSB released them. This site's own text never names anyone involved. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.