# NTSB DEN87LA100: Aero Commander A-9B, N2755V, Wood, SD, April 24, 1987

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Limited investigation · Final report
- Date: April 24, 1987, 11:15 local (16:15 UTC)
- Place: Wood, SD
- Coordinates: 43.490165, -100.479194 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=43.4902&lon=-100.4792&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: Minor injuries
- Injuries: 1 minor
- Status: Completed, report November 8, 1988
- Report: Approved by Office Director
- NTSB case key (mKey): 17204
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN87LA100
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/17204/pdf
- Page: https://openairdocs.org/ntsb/DEN87LA100

## Sequence of events

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

- Loss of engine power, maneuvering - aerial application
  - reason for occurrence undetermined (cause)
- Loss of control - in flight, maneuvering - turn to reverse direction
  - stall/mush - inadvertent, pilot in command (cause)
- In flight collision with terrain/water, descent - uncontrolled
  - terrain condition - crop

## Analysis

A COMMERCIAL AG PLT WAS WORKING A FIELD WITH 2-4-D AND HAD BEEN SPRAYING FOR 15 MINUTES. ON A TURN TO REVERSE DIRECTION AT THE END OF A PASS, THE PLT STARTED A 45 DEGREE BANK PULL UP AND ADDED FULL THROTTLE. THE ENGINE THEN HAD A PARTIAL POWER LOSS AND BEGAN TO LOSE RPM. THE ACFT STALLED AND FELL RIGHT WING FIRST, 200 FEET TO THE GROUND. THE ENGINE, RIGHT WING AND RIGHT MAIN GEAR SEPARATED AND THE FUSELAGE CAME TO REST 50 FEET FROM THE IMPACT POINT. AN IMMEDIATE POST ACCIDENT FIRE DESTROYED MOST OF THE WRECKAGE.

## Aircraft

- Registration: N2755V (not matched to a registry record)
- Reported make and model: AERO COMMANDER A-9B
- Category: Airplane
- Serial number: 1500
- Airframe hours: 2211
- Engines: LYCOMING TI0-540 290 horsepower reciprocating
- Damage: Destroyed
- Fire: On-Ground
- Flight: Aerial application, Part 137
- Operator: Oscar B. Thoreson, doing business as Ben'S Spraying Service, Inc.
- Registered owner: Oscar B Thoreson
- Airworthiness certificate: Special, Restricted (Special)
- Last inspection: Annual, March 10, 1987

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 54; commercial; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; seat: front; flight hours: 3,697 total, 62 in this make and model, 2,809 as pilot in command, 90 in the last 90 days, 6 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 330° at 8 knots
- Visibility: 10 statute miles
- Lowest ceiling: none

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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