# NTSB MKC90LA145: Monnett Sonerai II, N2MX, Cherokee, IA, July 13, 1990

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Limited investigation · Final report
- Date: July 13, 1990, 09:45 local (14:45 UTC)
- Place: Cherokee, IA
- Coordinates: 42.749027, -95.550949 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=42.7490&lon=-95.5509&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: Minor injuries
- Injuries: 1 minor
- Status: Completed, report November 9, 1992
- Report: Approved by Office Director
- NTSB case key (mKey): 35014
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=MKC90LA145
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/35014/pdf
- Page: https://openairdocs.org/ntsb/MKC90LA145

## Probable cause

AIRCRAFT CONTROL NOT MAINTAINED BY THE PILOT IN COMMAND.

## Sequence of events

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

- Airframe/component/system failure/malfunction, cruise
  - window,canopy - not secured (contributing factor)
  - window,canopy - popped/tripped (contributing factor)
  - aircraft control - not maintained, pilot in command (cause)
  - lack of familiarity with aircraft, pilot in command (contributing factor)
- Forced landing, descent - emergency
- Nose over, landing
  - terrain condition - none suitable (contributing factor)
  - terrain condition - ditch (contributing factor)

## Analysis

THE PVT PLT SAID THAT HE HAD JUST DEPARTED THE AIRPORT IN HIS NEWLY PURCHASED HOMEBUILT ACFT, HAD LEVELED OFF, WHEN THE CANOPY POPPED OPEN. HE REDUCED POWER, THEN HELD THE CANOPY PARTIALLY DOWN WITH HIS THROTTLE HAND. HE ATTEMPTED AN EMERGENCY LDG, AND FELT HE NEEDED ADDITIONAL POWER TO MAKE THE FIELD, BUT CHOSE TO HOLD THE CANOPY DOWN INSTEAD. HE LANDED IN AN ALFALFA FIELD, STRUCK A DITCH AND NOSED OVER. THE PLT SAID THAT HE CHOSE TO HOLD THE CANOPY DOWN, RATHER THAN RISK POSSIBLE ADVERSE FLIGHT CHARACTARISTICS WITH IT OPEN.

## Aircraft

- Registration: [N2MX](https://openairdocs.org/deregistered/N2MX-2020-10-31), registration cancelled 2020-10-31, S/N JM1, built 1973 (OpenAirDocs)
- Reported make and model: MONNETT SONERAI II
- Registry model: [John T Monnett JR MONNETT](https://openairdocs.org/model/john-t-monnett-jr-monnett) (registry code 05639AD) (OpenAirDocs)
- Registry engine: [Amateur-built UNKNOWN ENG](https://openairdocs.org/engine/amateur-built-unknown-eng) (registry code 99999) (OpenAirDocs)
- Category: Airplane, amateur-built
- Serial number: UM 1
- Engines: Volkswagen 2020 C.C. 65 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Christensen, Jim W.
- Registered owner: Unknown
- Airworthiness certificate: Special, Experimental (Special)
- Departed: CKP

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 33; private; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 3, valid medical--no waivers/lim.; flight hours: 268 total, 2 in this make and model, 268 as pilot in command, 11 in the last 90 days, 3 in the last 30 days, 2 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 20° at 3 knots
- Visibility: 20 statute miles
- Lowest ceiling: none
- Temperature: -0 °F, dew point -0 °F
- Observed at: SUX, 50 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 19900713025729A](https://openairdocs.org/incident/19900713025729A), Jul 13, 1990: Amtrmo SONERAI2, Cherokee, IA, Substantial damage. Canopy came open on climb to cruise elected to land in open field while holding canopy. Nosed over in alfalfa field

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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