# NTSB DEN06CA048: Enstrom 280F, N811Z, Peetz, CO, March 15, 2006

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Data collection · Final report
- Date: March 15, 2006, 11:00 local (18:00 UTC)
- Place: Peetz, CO
- Coordinates: 40.935276, -103.363609
- Nearby events: https://openairdocs.org/map.md?lat=40.9353&lon=-103.3636&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 2 uninjured
- Status: Completed, report July 31, 2006
- Report: Approved by Office Director
- NTSB case key (mKey): 63349
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN06CA048
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/63349/pdf
- Page: https://openairdocs.org/ntsb/DEN06CA048

## Probable cause

The pilot's failure to maintain aircraft control while maneuvering resulting in an impact with terrain.  Contributing factors were the gusty winds, downdrafts, and box canyon.

## Sequence of events

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

- Loss of control - in flight, maneuvering
  - weather condition - gusts (contributing factor)
  - aircraft control - not maintained, pilot in command (cause)
  - weather condition - downdraft (contributing factor)
- In flight collision with terrain/water, emergency descent/landing
  - remedial action - attempted, pilot in command
  - terrain condition - blind/box canyon (contributing factor)

## Analysis

While heading in a northwest direction at the edge of a box canyon, the helicopter encountered a "very strong burst down draft," and began to descend into the box canyon.  The pilot attempted to arrest the descent, but was unsuccessful.  Subsequently, the helicopter impacted the base of the canyon and came to rest upright.

## Factual narrative

According to the pilot, the purpose of the flight was aerial photography of wildlife nesting areas.  Prior to departure, the pilot checked the weather forecast, which called for calm winds and winds increasing in the afternoon.  As the helicopter approached the target area, the winds were "dead calm", and the pilot was "watching for the first signs of wind in the grass on the tops of the cliff areas and in the canyons below."  While heading in a northwest direction at the edge of a box canyon, the helicopter encountered a "very strong burst down draft," and began to descend into the box canyon.  The pilot attempted to arrest the descent, but was unsuccessful.  Subsequently, the helicopter impacted the base of the canyon and came to rest upright.

## Aircraft

- Registration: [N811Z](https://openairdocs.org/aircraft/N811Z), registered now, S/N 1508, built 1982 (OpenAirDocs)
- Reported make and model: Enstrom 280F
- Registry model: [Enstrom Helicopter 280F](https://openairdocs.org/model/enstrom-helicopter-280f) (registry code 3300550) (OpenAirDocs)
- Registry engine: [Lycoming HI0-360 series](https://openairdocs.org/engine/lycoming-hi0-360-series) (registry code 41553, turbo-shaft) (OpenAirDocs)
- Category: Helicopter
- Serial number: 1508
- Engines: Lycoming HIO-360-F1AD reciprocating
- Damage: Substantial damage
- Flight: Business, Part 91
- Registered owner: Avalair Helicopters, Inc.
- Airworthiness certificate: Standard, Normal
- Departed: SNY, SIDNEY, NE

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 57; commercial; airplane ratings: single-engine land; instrument ratings: helicopter; medical: class 2; flight hours: 2,803 total, 155 in this make and model, 47 in the last 90 days, 14 in the last 30 days

## Weather

- Conditions: Visual (VMC), Day

## 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 20060315005519A](https://openairdocs.org/incident/20060315005519A), Mar 15, 2006: Enstrm 280F, Sterling, CO, Substantial damage. (-23) Pilot was conducting an aerial photography flight (photographing eagles nests located on canyon walls). Aircraft was hovering in a narrow box canyon when…

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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