# NTSB SEA91LA093: Aeronca 7BCM, N81578, Elma, WA, April 20, 1991

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: April 20, 1991, 12:40 local (19:40 UTC)
- Place: Elma, WA
- Coordinates: 47.099876, -123.390983 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=47.0999&lon=-123.3910&mi=10
- Phase of flight: [Standing](https://openairdocs.org/ntsb-phases/150) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 2 uninjured
- Status: Completed, report February 8, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 41419
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA91LA093
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/41419/pdf
- Page: https://openairdocs.org/ntsb/SEA91LA093

## Probable cause

THE PILOT USED INADEQUATE STARTING PROCEDURES.  FACTORS TO THE ACCIDENT WERE:  THE PILOT DID NOT USE PROPER ASSISTANCE AND THE PASSENGER'S INADVERTENT CONTROL INTERFERENCE.

## Sequence of events

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

- On ground/water collision with object, standing - starting engine(s)
  - object - aircraft parked/standing
  - starting procedure - inadequate, pilot in command (cause)
  - proper assistance - not used, pilot in command (contributing factor)
  - control interference - inadvertent, passenger (contributing factor)

## Analysis

AT THE BEGINNING OF A FLIGHT, THE PILOT REPORTED THAT HE HAD PLACED CHOCKS IN FRONT OF THE MAIN LANDING GEAR AND RETURNED TO THE COCKPIT TO TURN ON THE FUEL.  THE PILOT THEN PROCEEDED TO THE PROPELLER TO PULL THE ENGINE THROUGH.  AS THE PILOT TURNED THE PROPELLER, THE ENGINE STARTED AT A HIGH RPM AND THE AIRCRAFT JUMPED THE CHOCKS.  THE PILOT TRIED TO HANG ONTO THE RIGHT WING AS IT SWUNG AROUND ONCE, MISSING THE FUEL PUMPS AND A PARKED PIPER.  THE AIRCRAFT CAME AROUND FOR THE SECOND TIME AND COLLIDED INTO THE RIGHT SIDE OF THE PIPER.

## Aircraft

- Registration: [N81578](https://openairdocs.org/aircraft/N81578), registered now, S/N 7AC-197, built 1945 (OpenAirDocs)
- Reported make and model: AERONCA 7BCM
- Registry model: [Aeronca 7BCM](https://openairdocs.org/model/aeronca-7bcm) (registry code 2110106) (OpenAirDocs)
- Registry engine: [Continental A&C75 series](https://openairdocs.org/engine/continental-a-c75-series) (registry code 17005, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 7AC-197
- Engines: CONTINENTAL A-65-9 65 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Michael A. Perdue
- Registered owner: Michael A. Perdue
- Destination: SHN, SHELTON, WA
- Airport: WA22, Elma

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 39; private; airplane ratings: single-engine land; medical: class 3, valid medical--w/ waivers/lim; flight hours: 192 total, 59 in this make and model, 116 as pilot in command, 45 in the last 90 days, 29 in the last 30 days, 3 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Visibility: 35 statute miles
- Lowest ceiling: none
- Temperature: -0 °F, dew point -0 °F

## 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 19910420011549A](https://openairdocs.org/incident/19910420011549A), Apr 20, 1991: Bbavia 7BCM, Elma, WA, Substantial damage. Hand propped startup. Aircraft jumped chocks and collided with parked aircraft. Brakes off and too much throttle.

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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