No fatalities

8 Aug 2014: AERONCA 7AC NO SERIES — Apple Valley, CA

Apple Valley, CA, United States

On 8 Aug 2014, an AERONCA 7AC NO SERIES was involved in an aviation accident near Apple Valley, CA. No fatalities were reported. Investigators recorded the probable cause as: The pilot's failure to adequately secure the airplane while hand-starting the engine. This summary draws on records from NTSB; 12 related events involving the same aircraft type or operator are linked below.

SourcesNTSBPrimary reportUpdated 1778583330Data APIEditorial standards

A pilot's attempt to hand-start an airplane resulted in the engine immediately reaching high RPM. The pilot lost control, and the unoccupied aircraft struck a parked helicopter and a fuel station kiosk, sustaining substantial wing and fuselage damage.

Incident Overview

A pilot reported that during preparation for flight, he verified the throttle position and chocked the right main landing gear with his foot. After starting the engine by hand-turning the propeller, the engine immediately accelerated to a high RPM. The pilot attempted to hold onto the airplane to regain control and reduce throttle, but was unsuccessful. The unoccupied airplane then collided with a parked helicopter and a fuel station kiosk before coming to a stop.

Sequence of Events

Prior to engine start, the pilot performed preflight checks including throttle position verification and securing the aircraft with a foot chock on the right main gear. He initiated the start by manually rotating the propeller. Upon starting, the engine rapidly increased to high power without any input from the pilot. Despite efforts to hold the airplane and reach the throttle, the pilot could not prevent the aircraft from moving forward. The airplane, with no one aboard, traveled across the ground, striking a stationary helicopter and a fuel kiosk. The impact caused substantial damage to the right wing and fuselage. The pilot reported no preimpact malfunctions or failures that would have precluded normal operation.

Investigation Findings

The investigation focused on the unexpected high RPM immediately following the hand start. The pilot stated that all pre-start checks were properly performed. No mechanical issues were identified that would have prevented normal engine operation. The accident sequence underscores the challenges of controlling an aircraft during an uncommanded high-power event on the ground. The damage to the right wing and fuselage was deemed substantial. No injuries were reported. The investigation did not assign a probable cause, as the pilot reported no preexisting malfunctions or failures.

Contributing factors

Causes

Pilotdown/mooring

Other contributing factors

Contributed to outcome