# NTSB DEN86LA025: Balloon Works Firefly 6B, N4052K, Englewood, CO, November 17, 1985

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Limited investigation · Final report
- Date: November 17, 1985, 08:45 local (15:45 UTC)
- Place: Englewood, CO
- Coordinates: 39.579967, -104.860008 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=39.5800&lon=-104.8600&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: Minor injuries
- Injuries: 1 minor, 1 uninjured
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 16885
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN86LA025
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/16885/pdf
- Page: https://openairdocs.org/ntsb/DEN86LA025

## Sequence of events

In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf).

- Airframe/component/system failure/malfunction, cruise - normal
  - fluid,fuel - water (contributing factor)
  - balloon equipment,burner system - unapproved part (cause)
  - balloon equipment,burner system - ice (contributing factor)
- Miscellaneous/other, landing
  - balloon equipment,envelope - burned (cause)

## Analysis

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.

## Aircraft

- Registration: N4052K (not matched to a registry record)
- Reported make and model: BALLOON WORKS FIREFLY 6B
- Category: Balloon
- Serial number: 10068
- Airframe hours: 276
- Engines: unknown
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: J. Robert Pendleton
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, April 11, 1985, 46 hours before
- Departed: ENGLEWOOD, CO
- Destination: ENGLEWOOD, CO

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 39; private; flight hours: 48 total, 34 in this make and model, 48 as pilot in command, 3 in the last 90 days, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 95° at 6 knots
- Visibility: 46 statute miles
- Lowest ceiling: 8,000 ft broken
- Temperature: 9 °F, dew point 9 °F
- Altimeter: 30.00 inHg
- Observed at: APA, 8 nm away

## FAA reports on this event (1)

The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs).

- [Accident 19851117061259A](https://openairdocs.org/incident/19851117061259A), Nov 17, 1985: Balwks FIREFLY6B, Englewood, CO, Substantial damage. Fire in envelope after landing. Blast valve stuck in open position allowing a continuous flame.

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

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