# NTSB DEN91LA137: Raven Ralley RX7, N4036Y, Englewood, CO, September 21, 1991

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: September 21, 1991, 07:45 local (13:45 UTC)
- Place: Englewood, CO
- Coordinates: 39.540466, -104.959022 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=39.5405&lon=-104.9590&mi=10
- Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 2 uninjured
- Status: Completed, report May 3, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 18140
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN91LA137
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/18140/pdf
- Page: https://openairdocs.org/ntsb/DEN91LA137

## Probable cause

A HARD LANDING AND INADVERTENT DEPLOYMENT OF THE BALLOON HEATER. A FACTOR WAS: INADVERTENT ENTANGLEMENT OF A LOAD CABLE WITH THE HEATER ACTIVATION DEVICE.

## Sequence of events

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

- Hard landing, landing - flare/touchdown
  - touchdown - abrupt, pilot in command (cause)
- Fire/explosion, landing - flare/touchdown
  - balloon equipment,burner system - deployed inadvertently (cause)
  - balloon equipment,suspension system/cables - entangled (contributing factor)

## Analysis

DURING AN ATTEMPTED LANDING, THE BALLOON TOUCHED DOWN HARD AND THE BASKET TIPPED OVER. A LOAD CABLE INADVERTENTLY TANGLED IN THE HEATER ACTIVATION DEVICE AND LIT THE BURNER WHICH SET THE ENVELOPE AND SURROUNDING GRASS ON FIRE. THE PILOT EXTINGUISHED BOTH FIRES.

## Aircraft

- Registration: [N4036Y](https://openairdocs.org/deregistered/N4036Y-2014-12-02), registration cancelled 2014-12-02, S/N RX7-304, built 1983 (OpenAirDocs)
- Reported make and model: RAVEN RALLEY RX7
- Registry model: [Raven Industries RALLY RX7](https://openairdocs.org/model/raven-industries-rally-rx7) (registry code 7480503) (OpenAirDocs)
- Registry engine: [NONE](https://openairdocs.org/engine/none) (registry code 00000, none) (OpenAirDocs)
- Category: Balloon
- Serial number: RX7-304
- Airframe hours: 201
- Engines: unknown
- Damage: Substantial damage
- Fire: On-Ground
- Flight: Personal, Part 91
- Operator: Frank J. Riehl
- Registered owner: James E. Long
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, May 18, 1991, 1 hours before
- Departed: NONE, ENGLEWOOD, CO

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 57; flight instructor, commercial; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; flight hours: 1,544 total, 121 in this make and model, 1,503 as pilot in command, 7 in the last 90 days, 2 in the last 30 days

## Weather

- Conditions: Visual (VMC), Day
- Wind: 90° at 10 knots
- Visibility: 20 statute miles
- Lowest ceiling: none
- Temperature: 70 °F, dew point 1 °F

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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