# NTSB SEA87LA107: Aerodynamics . Hawk Mkii, N5832M, Ellensburg, WA, June 1, 1987

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: May 31, 1987, 20:10 local (Jun 1, 1987, 03:10 UTC)
- Place: Ellensburg, WA
- Coordinates: 46.96994, -120.469818 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=46.9699&lon=-120.4698&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report May 2, 1988
- Report: Approved by Office Director
- NTSB case key (mKey): 40633
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA87LA107
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/40633/pdf
- Page: https://openairdocs.org/ntsb/SEA87LA107

## Sequence of events

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

- In flight encounter with weather, cruise
  - weather condition - mountain wave (contributing factor)
  - flight into known adverse weather - selected, pilot in command (cause)
  - weather condition - turbulence (contributing factor)
  - unsafe/hazardous condition warning - disregarded, pilot in command (cause)
- Airframe/component/system failure/malfunction, cruise
  - design stress limits of aircraft - exceeded, pilot in command (contributing factor)
- Forced landing, descent - emergency
  - precautionary landing - performed, pilot in command

## Analysis

DESPITE WARNINGS FROM THE FLIGHT SERVICE STATION ABOUT TURBULENCE, HIGH WINDS ALOFT, SEVERE LOW LEVEL WIND SHEAR, AND LOW CEILINGS ALONG THE PILOTS INTENDED ROUTE OF FLIGHT, THE PILOT ELECTED TO DEPART THE AIRPORT FOR HIS DESTINATION. STANDING LENTICULAR ALTOCUMULUS CLOUDS WERE ALSO PRESENT. WITHIN 1/2 HOUR OF DEPARTURE THE AIRCRAFT ENCOUNTERED SEVERE TURBULENCE CAUSING STRUCTURAL DAMAGE TO THE AIRCRAFT. THE PILOT WAS ABLE TO LAND THE AIRCRAFT SAFELY AT A NEARBY AIRPORT.

## Aircraft

- Registration: [N5832M](https://openairdocs.org/deregistered/N5832M-2011-04-12), registration cancelled 2011-04-12, S/N 8411-2 (OpenAirDocs)
- Reported make and model: AERODYNAMICS     . HAWK MKII
- Registry model: [Aero Dynamics SPARROW HAWK MKII](https://openairdocs.org/model/aero-dynamics-sparrow-hawk-mkii) (registry code 05613QY) (OpenAirDocs)
- Registry engine: [Bombardier ROTAX (ALL)](https://openairdocs.org/engine/bombardier-rotax-all) (registry code 09050, reciprocating) (OpenAirDocs)
- Category: Airplane, amateur-built
- Serial number: 8411-2
- Airframe hours: 200
- Engines: Rotax 532 48 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Rod Pederson
- Registered owner: Rod Pederson
- Airworthiness certificate: Special, Experimental (Special)
- Departed: EAT, WENATCHEE, WA
- Destination: S88, ARLINGTON, WA
- Flight plan: VFR

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 37; commercial; airplane ratings: single-engine land, multi-engine sea, single-engine sea, multi-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; seat: front; flight hours: 6,500 total, 100 in this make and model

## Weather

- Conditions: Visual (VMC), Day
- Wind: 300° at 14 knots
- Visibility: 30 statute miles
- Lowest ceiling: none
- Temperature: 54 °F, dew point 36 °F
- Altimeter: 29.00 inHg
- Observed at: EAT, 15 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 19870531080669A](https://openairdocs.org/incident/19870531080669A), May 31, 1987: Phlpow SPARROWHWKM5, Cle Elum, WA, Substantial damage. Encountered severe turbulence enroute that caused structual and other damage. Pilot was advised VFR not recommended

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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