# NTSB LAX84FU023: Motorized Gliders Tierra, Bullhead City, AZ, December 3, 1983

- Type: NTSB accident investigation
- Classification: Accident · Serious injuries · Final report
- Date: December 3, 1983, 09:12 local (16:12 UTC)
- Place: Bullhead City, AZ
- Location: 35.1478° N, 114.5683° W: Placed by OpenAirDocs: center of Bullhead City, AZ, within about 6 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=35.1478&lon=-114.5683&mi=10
- Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping)
- Highest injury: Serious injuries
- Injuries: 1 serious
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 24012
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX84FU023
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/24012/pdf
- Page: https://openairdocs.org/ntsb/LAX84FU023

## Sequence of events

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

- Loss of control - in flight, takeoff - initial climb
  - airspeed - not maintained, pilot in command (cause)
  - stall - inadvertent, pilot in command (cause)
  - lack of familiarity with aircraft, pilot in command (cause)
- In flight collision with terrain/water, takeoff - initial climb

## Analysis

ACCORDING TO THE PLT, HE HAD NO PREVIOUS FLT TIME IN ULTRALIGHT ACFT. BEFORE TAKING OFF, HE TAXIED THE ULTRALIGHT SEVERAL TIMES TO GET THE FEEL OF THE VEHICLE. DURING DEPARTURE, THE PLT TOOK OFF FROM A TAXI STRIP WEST OF RWY 17. THE STRIP WAS USED BY ULTRALIGHT PLTS FOR ALL TAKEOFFS & LANDINGS. THE PLT STATED THAT SHORTLY AFTER DEPARTING & WHILE NEGOTIATING A LEFT TURN, THE LEFT WING STALLED & THERE WAS INSUFFICIENT ALTITUDE TO RECOVER. ACCORDING TO THE OPERATOR, THE LEFT TURN WAS STARTED AT ABOUT 50 FT AGL, THEN THE ULTRALIGHT STALLED. HE FURTHER STATED THAT THE ENG SOUNDED NORMAL THRU-OUT THE SEQUENCE & THAT THE VEHICLE WAS CLIMBING AT A VERY SLOW SPEED BEFORE THE ACCIDENT. AN EXAM OF THE AIRFRAME & ENG DISCLOSED NO PREIMPACT, MECHANICAL MALFUNCTION OR FAILURE.

## Aircraft

- Registration: UNREG (not matched to a registry record)
- Reported make and model: MOTORIZED GLIDERS TIERRA
- Category: Ultralight, amateur-built
- Engines: ROTAX 337 35 horsepower reciprocating
- Damage: Substantial damage
- Flight: Instructional, Part 103
- Operator: Marvin L Robinson
- Registered owner: Motorized Gliders Of Iowa,Inc.
- Airport: P06, Bullhead City

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 38; private; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; seat: center

## Weather

- Conditions: Visual (VMC), Day
- Wind: 180° at 2 knots
- Visibility: 75 statute miles
- Lowest ceiling: none
- Temperature: 64 °F

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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