# NTSB MIA84FA104: Gross Benson B-8M, N3154A, Sanford, FL, March 12, 1984

- Type: NTSB accident investigation
- Classification: Accident · Fatal · Field investigation · Final report
- Date: March 12, 1984, 08:15 local (13:15 UTC)
- Place: Sanford, FL
- Coordinates: 28.809543, -81.330223 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=28.8095&lon=-81.3302&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: Fatal
- Injuries: 1 fatal
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 30978
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=MIA84FA104
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/30978/pdf
- Page: https://openairdocs.org/ntsb/MIA84FA104

## Sequence of events

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

- Loss of control - in flight, cruise
  - procedures/directives - not maintained, pilot in command (contributing factor)
  - inadequate training, pilot in command (contributing factor)
  - judgment - poor, pilot in command (contributing factor)
  - lack of total experience, pilot in command (contributing factor)
  - overconfidence in personal ability, pilot in command (contributing factor)
  - aircraft handling - not maintained, pilot in command (cause)
- In flight collision with object, descent - uncontrolled
  - object - tree(s) (contributing factor)
- In flight collision with terrain/water, descent - uncontrolled

## Analysis

THE STUDENT PLT & THE PLTS OF 2 OTHER BENSON GYROCOPTERS TOOK OFF FROM A PRIVATE STRIP & PROCEEDED TO FLY IN A LOOSE FORMATION. THE PLTS OF THE OTHER 2 GYROCOPTERS DID NOT WITNESS THE ACCIDENT, BUT NOTICED THAT 1 OF THE 3 WAS MISSING. WITNESSES ON THE GROUND STATED THAT THEY NOTICED THE GYROCOPTER OSCILLATED UP & DOWN AND FORE & AFT PRIOR TO IT IMPACTING WITH TREE TOPS. THE STUDENT PLT WAS NOT INDORSED FOR FLT IN ANY ACFT. HIS WIFE STATED THAT HE HAD RECEIVED INSTRUCTION BY USING A TRAINING DEVICE THAT WAS TOWED BEHIND A VEHICLE. NO SIGNS OR EVIDENCE OF PREEXISTING STRUCTURAL FAILURE WERE NOTED.

## Aircraft

- Registration: N3154A (not matched to a registry record)
- Reported make and model: GROSS BENSON B-8M (BENSON B-8)
- Category: Gyroplane, amateur-built
- Serial number: JAG-1
- Engines: McCulloch 4318-A reciprocating
- Damage: Destroyed
- Flight: Personal, Part 91
- Registered owner: Joseph A. Gross
- Departed: SANFORD, FL

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 33; student; medical: class 3, valid medical--no waivers/lim.; seat: center; toxicology performed; flight hours: 22 total, 22 in this make and model

## Weather

- Conditions: Visual (VMC), Day
- Wind: 70° at 8 knots
- Visibility: 12 statute miles
- Lowest ceiling: 30,000 ft broken
- Altimeter: 30.00 inHg
- Observed at: MCO, 26 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 19840312041009A](https://openairdocs.org/incident/19840312041009A), Mar 12, 1984: Amtrbx BENSENB8M, Sanford, FL, Destroyed. Began to porpoise in flight. Indicates coning and flapping occurred. Broke off mastand prop blades. Crashed in trees.

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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