# NTSB CHI87DEP03: Erickson Sonerai 2L, N131DE, Algoma, WI, April 7, 1987

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Final report
- Date: April 7, 1987, 10:50 local (15:50 UTC)
- Place: Algoma, WI
- Coordinates: 44.599948, -87.439956 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=44.5999&lon=-87.4400&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report November 2, 1989
- Report: Approved by Office Director
- NTSB case key (mKey): 13574
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI87DEP03
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/13574/pdf
- Page: https://openairdocs.org/ntsb/CHI87DEP03

## Sequence of events

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

- Loss of engine power(total) - mech failure/malf, cruise - normal
  - engine assembly,crankshaft - failure,total (cause)
- Forced landing, descent - emergency
- Hard landing, landing - flare/touchdown
  - flare - improper, pilot in command (cause)
  - landing gear,nose gear - overload

## Analysis

WHILE IN NORMAL CRUISE FLIGHT THE CRANKSHAFT FAILED AT THE PROPELLER FLANGE AND THE PROPELLER DEPARTED THE AIRCRAFT. THE PILOT EXECUTED A FORCED LANDING TO A FARM FIELD. HE WAS UNABLE TO FLARE SUCCESSFULLY AND LOST CONTROL DURING LANDING.

## Aircraft

- Registration: [N131DE](https://openairdocs.org/deregistered/N131DE-1991-09-04), registration cancelled 1991-09-04, S/N 01312L (OpenAirDocs)
- Reported make and model: ERICKSON SONERAI 2L
- Registry model: [Erickson Donald Lee SONERAI IIL](https://openairdocs.org/model/erickson-donald-lee-sonerai-iil) (registry code 056595J) (OpenAirDocs)
- Category: Airplane, amateur-built
- Serial number: 01312L
- Airframe hours: 36
- Engines: VOLKSWAGEN 2180CC 74 horsepower reciprocating
- Damage: Destroyed
- Fire: On-Ground
- Flight: Personal, Part 91
- Operator: Byron E. Giovannetti
- Registered owner: Byron E Giovannetti
- Airworthiness certificate: Special, Experimental (Special)
- Departed: MKE, MILWAUKEE, WI

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 37; commercial; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 3, invalid medical for flight; seat: rear; flight hours: 1,384 total, 32 in this make and model, 1,189 as pilot in command, 23 in the last 90 days, 13 in the last 30 days, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 40° at 12 knots
- Visibility: 10 statute miles
- Lowest ceiling: none
- Temperature: 54 °F, dew point 34 °F
- Altimeter: 30.00 inHg
- Observed at: GRB, 32 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 19870407008699A](https://openairdocs.org/incident/19870407008699A), Apr 7, 1987: Amtrmo SONERAI2, Algoma, WI, Destroyed. Lost the propeller and crash landed. Found forward end of crankshaft had broken due to torsional overload.

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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