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Accidents · NTSB DEN86LA025 · Preliminary: the investigation is not finished

Balloon Works FIREFLY 6B accident near Englewood, Colorado, November 17, 1985

On November 17, 1985 at about 3:45 pm local time, a Balloon Works FIREFLY 6B, registered N4052K, was substantially damaged in an accident near Englewood, Colorado. It was a personal flight under general aviation rules (Part 91). 1 person had minor injuries; 1 other was unhurt. The weather was visual conditions (good weather).

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The NTSB's probable cause their words, unchanged

The NTSB has not yet published a probable cause for this accident. Investigations usually take one to two years; this page updates when the final report is released.

Source: NTSB aviation accident database, copy made October 4, 2026. Docket and reports at the NTSB.

What the record shows

Date
November 17, 1985 · about 3:45 pm local time
Place
Englewood, Colorado · map
Type
Accident
Injuries
1 person had minor injuries; 1 other was unhurt.
Weather
visual conditions (good weather)
Aircraft
Balloon Works FIREFLY 6B · all FIREFLY 6Bs on the register
Registration
N4052K · no longer on the register · serial 10068
Damage
Substantial damage
Flight
Personal flight · general aviation rules (Part 91)

The NTSB's narrative final · quoted from the NTSB record

THE PLT STATED THAT WHILE ON A BALLOON FLT, THE BLAST VALVE, WHICH OPERATES THE BURNER FLAME, STUCK OPEN DURING ONE OF THE BURNS. THE PLT ATTEMPTED UNSUCCESSFULLY TO DISENGAGE THE BLAST VALVE. WHEN THE PLT COULD NOT STOP THE FLAME WITH THE BLAST VALVE, HE MANUALLY CLOSED THE THREE PROPANE TANKS. TO LAND, THE PLT OPENED A PROPANE TANK, RELIGHTING EACH TIME HE WISHED TO MAKE A BURN. UPON LANDING, THE ENVELOPE SHIFTED OVER THE FLAME, BURNING SEVEN GORE PANELS.

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: private
  • Ratings: rotorcraft: balloon
  • Flight time: 48 hours in all; 34 in this make and model; 3 in the last 90 days; 48 as pilot in command
  • Medical certificate: None
  • Seat: unk

The aircraft

  • Airframe total time: 276 hours
  • Last inspection: annual inspection, April 11, 1985; 46 hours since
  • Maximum gross weight: 1,050 lb
  • Landing gear: fixed
  • Engine: (type not recorded); 0 hours total

The flight

  • Departed from: Englewood CO at 2:30 pm
  • Destination: Englewood CO
  • Flight plan: none
  • Runway 0

Weather at the time

  • Light: daylight
  • Wind: from 095° at 6 knots
  • Visibility: 46 statute miles
  • Sky: broken clouds at 8,000 ft
  • Temperature: 9°F (-13°C), dew point 9°F (-13°C)
  • Altimeter: 30.00 inHg
  • Observation at 3:45 pm from APA, 8 miles away

Injuries

FatalSeriousMinorNone
Crew1
Passengers1

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 N4052K the same tail number, which may have belonged to a different aircraft at the time

2001-07-02LAX01LA232 · accident near Hayward, CA · substantial damage · minor injuries

About this page

Everything above comes from the NTSB's public accident database: the narrative, probable cause and findings are the NTSB's own words, and the coded tables behind its report (pilot, aircraft, flight, weather, injuries, sequence of events) are written out in plain English. Pilots' ages, home towns and medical details are left out on purpose. The documents and photographs are the NTSB's docket, the folder of records gathered during the investigation, shown as the NTSB released them (the NTSB redacts some personal details first) and listed under the NTSB's own titles. This site's own text never names pilots, passengers or anyone else involved. A preliminary report describes what is known soon after the event and can change; the final report, with the probable cause, usually follows one to two years later and this page is refreshed when it does. Case number DEN86LA025.