Casualties unknown

1947 Covilhã Olive Tree Collision: CS-ABK Accident Report

Covilhã, PT

On December 8, 1947, a Piper J-3 Cub (registration CS-ABK) was involved in an aviation accident near Covilhã, PT. Investigators recorded the probable cause as: Poor piloting during low-level flight resulted in a collision with an olive tree, causing wing deformation and loss of control. This summary draws on records from the Portuguese Office for the Prevention and Investigation of Accidents in Civil Aviation and Rail (GPIAAF); 1 related events involving the same aircraft type or operator are linked below.

Sourcesthe Portuguese Office for the Prevention and Investigation of Accidents in Civil Aviation and Rail (GPIAAF)Primary reportUpdated 2026-09-13Data APIEditorial standards

A Portuguese-registered aircraft collided with an olive tree near the Covilhã aerodrome in 1947 due to poor piloting during low-level flight, resulting in minor injuries and significant damage.

What happened

On December 8, 1947, a light aircraft registered as CS-ABK was involved in an accident near the Covilhã aerodrome in Portugal. The aircraft departed at 15:30 local time, carrying a pilot and one passenger. During the flight, the crew conducted maneuvers between the city of Covilhã and Tertozendo, eventually flying over an olive grove located north of the runway.

At approximately 15:50, while performing low-level flight operations, the aircraft struck an olive tree within the grove. The impact caused deformation to the right wing, leading the aircraft into a half-loop spin before crashing to the ground. Both the pilot and the passenger sustained minor injuries. The aircraft suffered extensive damage; accessory components such as the carburetor, air intake, oil tank, engine mount, exhaust, heater, and propeller were destroyed. The fuselage was largely disassembled, with only the empennage remaining intact.

The investigation

The investigation was conducted by the Directorate General of Civil Aviation (Direcção Geral da Aeronáutica Civil). Authorities interviewed the pilot and the Director of the Civil Aviation School in Covilhã. While the pilot claimed the aircraft entered a stall before hitting the ground, investigators disputed this account. They noted that given the aircraft's characteristics and its altitude of approximately 10 meters above the ground, it was unlikely to have entered a spin naturally. Instead, the impact with the obstacle deformed the wing, which directly caused the subsequent loss of control.

Findings

The investigation concluded that the primary cause of the accident was poor piloting. The crew's decision to conduct low-level maneuvers in proximity to obstacles led to the collision. The structural damage rendered the aircraft economically unrecoverable, and it was deemed unfit for restoration. The engine required careful inspection if any future use were considered.

Safety action

In response to this incident, authorities recommended that such low-level flight operations be prohibited in the area, or strictly enforced if already banned, to prevent similar accidents involving obstacles near aerodromes.

Probable cause

Poor piloting during low-level flight resulted in a collision with an olive tree, causing wing deformation and loss of control.