# NTSB SEA88LA009: Napper Vancraft, N49694, Pocatello, ID, October 17, 1987

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: October 17, 1987, 13:00 local (19:00 UTC)
- Place: Pocatello, ID
- Coordinates: 42.360652, -111.370925 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=42.3607&lon=-111.3709&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report December 27, 1988
- Report: Approved by Office Director
- NTSB case key (mKey): 40753
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA88LA009
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/40753/pdf
- Page: https://openairdocs.org/ntsb/SEA88LA009

## Sequence of events

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

- Airframe/component/system failure/malfunction, maneuvering
  - flight control,rudder - separation (cause)
  - flt control syst,rudder control - disabled (cause)
- Loss of control - in flight, maneuvering
  - spiral - uncontrolled, pilot in command
  - autorotation - performed, pilot in command
- In flight collision with terrain/water, descent - uncontrolled

## Analysis

THE EXPERIMENTAL GYROCOPTER WAS ON A TEST FLIGHT WHEN THE RIGHT RUDDER PEDAL PIVOT BOLT BROKE. THE AIRCRAFT BEGAN A SPIRAL IN A COUNTER-CLOCKWISE DIRECTION WITH THE RUDDER SEPARATING FROM THE AIRCRAFT AT THE HINGE POINTS. THE AIRCRAFT CONTINUED TO SPIRAL TO THE GROUND TO IMPACT.

## Aircraft

- Registration: [N49694](https://openairdocs.org/deregistered/N49694-1991-04-10), registration cancelled 1991-04-10, S/N 519489457 (OpenAirDocs)
- Reported make and model: NAPPER VANCRAFT
- Registry model: [Napper Paul R VANCRAFT](https://openairdocs.org/model/napper-paul-r-vancraft) (registry code 13027C7) (OpenAirDocs)
- Category: Airplane, amateur-built
- Serial number: 519489457
- Airframe hours: 9
- Engines: Volkswagen 2200CC 60 horsepower reciprocating
- Damage: Destroyed
- Flight: Part 91
- Registered owner: Paul R. Napper
- Airworthiness certificate: Special, Experimental (Special)
- Last inspection: Continuous airworthiness, September 1, 1986
- Airport: PIH, Pocatello Municipal

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 45; private; airplane ratings: single-engine land; medical: class 3, valid medical--w/ waivers/lim; seat: front; flight hours: 280 total, 17 in this make and model, 236 as pilot in command, 19 in the last 90 days, 2 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 260° at 9 knots
- Visibility: 40 statute miles
- Lowest ceiling: none
- Temperature: 55 °F, dew point 30 °F
- Altimeter: 30.00 inHg
- Observed at: PIH, 2 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 19871017059949A](https://openairdocs.org/incident/19871017059949A), Oct 17, 1987: Amtrnp VANCRAFT, Pocatello, ID, Destroyed. Right rudder pivot bolt broke. Lost control of aircraft. Impacted ground tail first. Undergoing flight tests.

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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