# NTSB SEA02LA126: Cosmos Phase II, Deer Park, WA, July 10, 2002

- Type: NTSB accident investigation
- Classification: Accident · Serious injuries · Limited investigation · Final report
- Date: July 9, 2002, 20:30 local (Jul 10, 2002, 03:30 UTC)
- Place: Deer Park, WA
- Coordinates: 47.966667, -117.416664
- Nearby events: https://openairdocs.org/map.md?lat=47.9667&lon=-117.4167&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: Serious injuries
- Injuries: 1 serious
- Status: Completed, report April 8, 2003
- Report: Approved by Office Director
- Parties: FAA-FSDO
- NTSB case key (mKey): 55182
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA02LA126
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/55182/pdf
- NTSB docket: https://data.ntsb.gov/Docket?ProjectID=55182
- Page: https://openairdocs.org/ntsb/SEA02LA126

## Probable cause

Loss of control for undetermined reasons.

## Sequence of events

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

- Loss of control - in flight, climb
  - aircraft control - not maintained
  - reason for occurrence undetermined (cause)
- In flight collision with terrain/water, descent - uncontrolled

## Analysis

The non-certified pilot was operating an unregistered experimental Cosmos Phase II Trike.   A witness to the accident reported that the aircraft entered a left turn shortly after departing the runway.  He reported that the aircraft reached an altitude of approximately 200 feet above ground level (AGL) and then began to descend.  The aircraft continued a descending left turn until it impacted terrain.  The witness reported that this was the pilot's first solo flight in the accident aircraft.  During a telephone interview, the pilot reported that he was unable to recall any of the detailed events surrounding the accident.

## Factual narrative

On July 9, 2002, at 2030 Pacific daylight time, an unregistered experimental Cosmos Phase II Trike sustained substantial damage after colliding with terrain shortly after takeoff from the Deer Park Airport, Deer Park, Washington.  The aircraft was owned by the non-certified pilot, and was being operated as a visual flight rules (VFR) flight under the provisions of Title 14, CFR Part 91.  The pilot, the sole occupant of the two-seat aircraft, sustained serious injuries.  Visual meteorological conditions prevailed and no flight plan had been filed for the local flight.

A witness to the accident reported that the aircraft entered a left turn shortly after departing runway 14.  He reported that the aircraft reached an altitude of approximately 200 feet above ground level (AGL) and then began to descend.  The aircraft continued a descending left turn until it impacted terrain.  The witness reported that this was the pilots first solo flight in the accident aircraft.

During a telephone interview with the National Transportation Safety Board, the pilot reported that he was unable to recall any of the detailed events surrounding the accident.

## Aircraft

- Registration: UNREG (not matched to a registry record)
- Reported make and model: Cosmos Phase II
- Category: Airplane, amateur-built
- Engines: Rotax 503 DC 52 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Registered owner: Donald Vanderhoof
- Departed: DEW, Deer Park, WA
- Airport: 07S, Deer Park, runway 14, 2,400 × 80 ft, grass/turf

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; injuries: serious; flight hours: 35 total, 35 in this make and model

## Weather

- Conditions: Visual (VMC), Day
- Wind: 20° at 7 knots
- Visibility: 10 statute miles
- Lowest ceiling: none
- Temperature: 75 °F, dew point 55 °F
- Altimeter: 29.82 inHg
- Observed at: KDEW

## Docket (1 files)

The files NTSB released with the investigation on December 31, 2002, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=55182. 313 KB in all.

- Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 313 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40461240&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF

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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