# NTSB LAX87DVD05: Rotorway Scorpion 133, N25059, Boonville, CA, September 27, 1987

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Final report
- Date: September 27, 1987, 10:00 local (17:00 UTC)
- Place: Boonville, CA
- Coordinates: 38.989463, -123.36016 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=38.9895&lon=-123.3602&mi=10
- Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report March 31, 1989
- Report: Approved by Office Director
- NTSB case key (mKey): 25337
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX87DVD05
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/25337/pdf
- Page: https://openairdocs.org/ntsb/LAX87DVD05

## Sequence of events

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

- In flight collision with terrain/water, landing - flare/touchdown
  - flare - improper, pilot in command (cause)
  - altitude - misjudged, pilot in command (cause)
  - lack of total experience, pilot in command (contributing factor)
- Roll over, landing

## Analysis

THE PLT SAID THAT WHEN HE WAS PRACTICING QUICK STOPS & FLARES, THE TAIL ROTOR STRUCK THE GROUND. THE HELICOPTER THEN YAWED, TOUCHED DOWN (RIGHT SKID 1ST) & ROLLED OVER. NO PREIMPACT MECHANICAL FAILURE OR MALFUNCTION WAS RPRTD.

## Aircraft

- Registration: N25059 (not matched to a registry record)
- Reported make and model: ROTORWAY SCORPION 133 (SCORPION 1)
- Category: Helicopter, amateur-built
- Serial number: S1331357
- Airframe hours: 245
- Engines: ROTORWAY RW-133 133 horsepower reciprocating
- Damage: Destroyed
- Flight: Personal, Part 91
- Operator: Palmer, William R.
- Registered owner: William R Palmer
- Airworthiness certificate: Special, Experimental (Special)
- Last inspection: 100 hour, July 10, 1987, 37 hours before
- Departed: PALMER RANCH, CA

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 43; student; medical: class 3, valid medical--no waivers/lim.; seat: left; flight hours: 79 total, 66 in this make and model, 53 as pilot in command, 10 in the last 90 days, 10 in the last 30 days, 2 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: calm
- Visibility: 15 statute miles
- Lowest ceiling: none
- Temperature: 63 °F, dew point 48 °F
- Altimeter: 30.00 inHg
- Observed at: UKI

## 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 19870927056339A](https://openairdocs.org/incident/19870927056339A), Sep 27, 1987: Amtrrw SCORPION*, Boonville, CA, Destroyed. The tail rotor and right skid hit the ground causing dynamic rollover. Student was practicing rapid decelerations.

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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