# NTSB DEN93LA016: Piper PA-18-150, N4384A, Boulder, CO, December 19, 1992

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: December 19, 1992, 16:30 local (23:30 UTC)
- Place: Boulder, CO
- Coordinates: 39.970294, -105.209167 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=39.9703&lon=-105.2092&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report June 11, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 18265
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN93LA016
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/18265/pdf
- Page: https://openairdocs.org/ntsb/DEN93LA016

## Probable cause

THE PILOT'S FAILURE TO EVALUATE CHANGING WEATHER CONDITIONS.

## Sequence of events

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

- In flight encounter with weather, maneuvering
  - weather condition - fog
  - weather evaluation - not performed, pilot in command (cause)
- On ground/water collision with object, landing - roll
  - precautionary landing - performed, pilot in command
  - terrain condition - roadway/highway
  - object - fence post
- Nose over, landing - roll

## Analysis

DURING AN AERIAL TOW, FOG CLOSED IN.  WHEN THE GLIDER WAS RELEASED THE AIRPORT WAS OBSCURED.  THE GLIDER LANDED WITH NO DAMAGE OR INJURY.  THE TOW PLANE ATTEMPTED TO LAND ON A ROAD AND DURING LANDING ROLL CAUGHT A WING TIP ON A POST. THE AIRCRAFT NOSED OVER.

## Aircraft

- Registration: [N4384A](https://openairdocs.org/aircraft/N4384A), registered now, S/N 18-4792, built 1956 (OpenAirDocs)
- Reported make and model: PIPER PA-18-150
- Registry model: [Piper PA-18-150](https://openairdocs.org/model/piper-pa-18-150) (registry code 7101828) (OpenAirDocs)
- Registry engine: [Lycoming O&VO-360 series](https://openairdocs.org/engine/lycoming-o-vo-360-series) (registry code 41514, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 18-4792
- Airframe hours: 8952
- Engines: LYCOMING O-360-A3A 180 horsepower reciprocating
- Damage: Substantial damage
- Flight: Other work use, Part 91
- Operator: The Cloud Base, Inc
- Registered owner: The Cloud Base, Inc
- Airworthiness certificate: Standard, Normal; Standard, Utility
- Last inspection: Annual, July 1, 1992, 160 hours before
- Departed: IV5, BOULDER, CO
- Destination: IV5

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 43; commercial, flight instructor; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 2, valid medical--no waivers/lim.; seat: front; flight hours: 7,435 total, 3,000 in this make and model, 7,301 as pilot in command, 88 in the last 90 days, 25 in the last 30 days

## Weather

- Conditions: Instrument (IMC), Day
- Wind: 320° at 10 knots
- Temperature: 12 °F, dew point 9 °F
- Altimeter: 29.00 inHg
- Observed at: BJC, 20 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 19921219050949A](https://openairdocs.org/incident/19921219050949A), Dec 19, 1992: Piper PA18150, Boulder, CO, Substantial damage. After releasing glider on aerial tow was unable to locate airport due fog. Wing hit fence post landing on a road.

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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