# NTSB DEN92LA001: Enstrom F-28C, N552H, Evergreen, CO, October 2, 1991

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: October 2, 1991, 17:00 local (23:00 UTC)
- Place: Evergreen, CO
- Coordinates: 39.629707, -105.339904 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=39.6297&lon=-105.3399&mi=10
- Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 2 uninjured
- Status: Completed, report May 5, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 18174
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN92LA001
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/18174/pdf
- Page: https://openairdocs.org/ntsb/DEN92LA001

## Probable cause

IN FLIGHT ENCOUNTER WITH A SUDDEN DOWNDRAFT.  A FACTOR WAS:  THE PILOT'S LACK OF TOTAL EXPERIENCE IN AIRCRAFT TYPE.

## Sequence of events

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

- Loss of control - in flight, takeoff - initial climb
  - weather condition - downdraft (cause)
  - lack of total experience in type of aircraft, pilot in command (contributing factor)
- Forced landing, descent - emergency
- In flight collision with terrain/water, landing - flare/touchdown
  - terrain condition - mountainous/hilly

## Analysis

THE PILOT SAID HE LIFTED THE HELICOPTER OFF THE GROUND BUT BEFORE TRANSLATONAL LIFT WAS ACHIEVED, HE ENCOUNTERED A SUDDEN DOWNDRAFT.  THE PILOT MADE A CONTROLLED CRASH BETWEEN TREES IN MOUNTAINOUS TERRAIN.

## Aircraft

- Registration: [N552H](https://openairdocs.org/deregistered/N552H-2004-06-04), registration cancelled 2004-06-04, S/N 347, built 1976 (OpenAirDocs)
- Reported make and model: ENSTROM F-28C
- Registry model: [Enstrom F-28C](https://openairdocs.org/model/enstrom-f-28c) (registry code 3300407) (OpenAirDocs)
- Registry engine: [Lycoming HIO-360 series](https://openairdocs.org/engine/lycoming-hio-360-series) (registry code 41524, reciprocating) (OpenAirDocs)
- Category: Helicopter
- Serial number: 347
- Engines: LYCOMING HIO-360-E14D 205 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: James B. Highbanks
- Registered owner: James B. Highbanks

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 52; flight engineer, commercial, airline transport; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 1, valid medical--w/ waivers/lim; flight hours: 16,000 total, 80 in this make and model, 12,000 as pilot in command, 180 in the last 90 days, 42 in the last 30 days

## Weather

- Conditions: Visual (VMC), Day
- Wind: calm
- Visibility: 50 statute miles
- Lowest ceiling: none
- Temperature: -0 °F, dew point -0 °F

## 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 19911002044489A](https://openairdocs.org/incident/19911002044489A), Oct 2, 1991: Enstrm F28C, Evergreen, CO, Substantial damage. Encountered unrecoverable down draft before translational lift on climbout. Crashed landed in opening between trees

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.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.