# NTSB DEN87FA069: Raven S-77A, N40968, Park City, UT, March 21, 1987

- Type: NTSB accident investigation
- Classification: Accident · Fatal · Field investigation · Final report
- Date: March 21, 1987, 11:00 local (18:00 UTC)
- Place: Park City, UT
- Coordinates: 40.639411, -111.489257 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=40.6394&lon=-111.4893&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: Fatal
- Injuries: 1 fatal, 8 serious
- Status: Completed, report March 10, 1988
- Report: Approved by Office Director
- NTSB case key (mKey): 17100
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN87FA069
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/17100/pdf
- Page: https://openairdocs.org/ntsb/DEN87FA069

## Sequence of events

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

- In flight collision with object, descent
  - object - wire,transmission (contributing factor)
  - visual lookout - inadequate, pilot in command (cause)
  - weather condition - unfavorable wind (contributing factor)
  - in-flight planning/decision - improper, pilot in command (cause)
  - clearance - not maintained, pilot in command (cause)
  - emergency procedure - not followed, pilot in command (cause)
- In flight collision with terrain/water, descent - uncontrolled

## Analysis

WHILE ON A COMMERCIAL PAX SIGHTSEEING FLT, THE PLT ALLOWED A NON-RATED STUDENT PLT TO FLY THE BALLOON UNTIL IT NEARLY COLLIDED WITH BUILDINGS. THE PLT TOOK OVER THE CONTROLS AND APPLIED MAXIMUM BURNER HEATING TO AVOID IMPACT WITH THE BUILDINGS, WHICH RESULTED IN RAPID ASCENT TO APPROXIMATELY 3,000 FEET AGL. WINDS AT THAT ALTITUDE BLEW THE BALLOON OUT OF THE SMALL OPEN VALLEY WHERE THE FLTS WERE NORMALLY CONDUCTED. IT CROSSED A RIDGELINE AND WAS FLYING OVER MOUNTAINOUS/HILLY TERRAIN WHERE THE PLT INITIATED A DESCENT FOR LANDING. THE BALLOON IMPACTED TRANSMISSION POWER LINES AT APPROXIMATELY 50 FEET ABOVE THE GROUND. THE GONDOLA WAS SEVERED FROM THE BALLOON BY ELECTRICAL ARCING AND FELL TO THE GROUND. THE NATURAL GAS FUEL TANKS EXPLODED AND BURNED, DESTROYING THE GONDOLA.

## Aircraft

- Registration: [N40968](https://openairdocs.org/deregistered/N40968-2018-01-18), registration cancelled 2018-01-18, S/N S77A-107, built 1983 (OpenAirDocs)
- Reported make and model: RAVEN S-77A
- Registry model: [Raven Industries S77A](https://openairdocs.org/model/raven-industries-s77a) (registry code 7480650) (OpenAirDocs)
- Registry engine: [NONE](https://openairdocs.org/engine/none) (registry code 00000, none) (OpenAirDocs)
- Category: Balloon
- Serial number: S77A-107
- Airframe hours: 280
- Engines: unknown
- Damage: Destroyed
- Fire: On-Ground
- Flight: Part 91
- Registered owner: Michael C. Bauwens
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, August 25, 1986, 70 hours before
- Departed: PARK CITY, UT

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 28; commercial; flight hours: 318 total, 318 in this make and model, 278 as pilot in command, 70 in the last 90 days, 2 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 170° at 14 knots
- Visibility: 40 statute miles
- Lowest ceiling: 20,000 ft broken
- Temperature: 39 °F, dew point 18 °F
- Altimeter: 29.00 inHg
- Observed at: SLC, 16 nm away

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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