Casualties unknown

1990-04-24: Bell 47D1 (N2134) — Dennis M. Hoppe — Hickman, KY

Hickman, KY, US

On April 24, 1990, a Bell 47D1 (registration N2134) operated by Dennis M. Hoppe was involved in an aviation accident near Hickman, KY. Investigators recorded the probable cause as: The pilot's entry into a settling-with-power condition during a downwind turn-around maneuver, which resulted in the helicopter rolling over after the spray booms became entangled in the tall wheat crop. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.

Sourcesthe U.S. National Transportation Safety Board (NTSB) historical archivePrimary reportUpdated 1781061362Data APIEditorial standards

A helicopter experienced a settling-with-power condition and rolled over while conducting agricultural spraying operations, resulting in significant damage to the aircraft.

What happened

The pilot was engaged in agricultural aerial application activities, specifically treating a wheat field with chemicals. After completing an initial pass, the pilot executed a turn-around maneuver directed downwind to initiate another swath run. During this phase of flight, the pilot reported entering a settling-with-power condition. This aerodynamic state persisted and continued to affect the aircraft's descent rate as it approached the ground.

As the helicopter descended, the tall wheat stalks in the field wrapped around the spray booms attached to the aircraft. The entanglement of the vegetation caused the helicopter to roll over upon impact with the ground.

The investigation

The investigation focused on the mechanical condition of the helicopter and the circumstances surrounding the accident. Evidence indicated that the tall wheat crop played a significant role in the final moments of the flight. The vegetation wrapped around the spray booms, which contributed to the loss of control and the subsequent rollover.

Findings

The primary factor identified was the pilot's entry into a settling-with-power condition during the low-altitude maneuvering phase. This condition, combined with the environmental obstacle of the tall wheat field, led to the accident. The entanglement of the spray booms in the crop prevented recovery and resulted in the aircraft rolling over.

Safety message

Pilots conducting agricultural operations should be aware of the risks associated with settling-with-power, particularly when maneuvering at low altitudes near obstacles such as tall crops. Proper energy management and awareness of ground effects are critical to preventing similar incidents.

Probable cause

The pilot's entry into a settling-with-power condition during a downwind turn-around maneuver, which resulted in the helicopter rolling over after the spray booms became entangled in the tall wheat crop.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001212X22843. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.