Balloon Works FIREFLY X-7 accident near Altoona, Iowa, September 7, 1991
On September 7, 1991 at about 12:30 pm local time, a Balloon Works FIREFLY X-7, registered N4055T, was involved in an accident near Altoona, Iowa. It was a personal flight under general aviation rules (Part 91). 1 person was seriously injured; 2 others were unhurt. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
WEATHER EVALUATION MISJUDGED AND OVERCONFIDENCE IN PERSONAL ABILITY. A FACTOR RELATED TO THE ACCIDENT WAS HIGH WINDS.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- September 7, 1991 · about 12:30 pm local time
- Place
- Altoona, Iowa · map
- Type
- Accident
- Injuries
- 1 person was seriously injured; 2 others were unhurt.
- Weather
- visual conditions (good weather)
- Aircraft
- Balloon Works FIREFLY X-7 FIREFLY X-
- Registration
- N4055T · no longer on the register · serial 10136
- Damage
- Not recorded
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
THE PILOT SAID THAT WHILE ATTEMPTING A HIGH WIND LANDING, THE GONDOLA HIT THE TERRAIN HARD, AND TIPPED OVER. A PASSENGER SUFFERED A BROKEN ANKLE DURING THE LANDING.
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: 247 hours in all; 200 in this make and model; 6 in the last 90 days; 4 in the last 30 days; 247 as pilot in command
- Medical certificate: None
- Seat: unk
The aircraft
- Last inspection: inspection type not recorded; 0 hours since
- Maximum gross weight: 1,600 lb
- Landing gear: fixed
- Engine: (type not recorded); 0 hours total
The flight
- Departed from: Altoona IA at 12:10 pm
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 150° at 6 knots
- Visibility: 5 statute miles
- Sky: scat at 25,000 ft
- Temperature: 0°F (-18°C), dew point 0°F (-18°C)
- Observation at 12:00 pm from DSM, 10 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 | |||
| Passengers | 1 | 1 |
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.
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.