No fatalities

Helicopter Impacts Tree and Terrain After Encountering Fog During Night Departure

Sedro Woolley, WA, United States

On October 18, 2013, a ROBINSON R44 - II II operated by Kurt Mayhall was involved in an aviation accident near Sedro Woolley, WA. No fatalities were reported. Investigators recorded the probable cause as: The non-instrument rated pilot's inadvertent encounter with instrument meteorological conditions during initial climb and his improper decision to continue flight, which resulted in an in-flight impact with a tree and an emergency descent that resulted in a… This summary draws on records from NTSB; 12 related events involving the same aircraft type or operator are linked below.

SourcesNTSBPrimary reportUpdated 2026-08-03Data APIEditorial standards

A helicopter on a night departure encountered a thick fog layer at 65 feet AGL, lost visual reference, struck a tree, and sustained substantial damage during an emergency descent.

Accident Overview

A pilot reported that prior to a night departure, he checked weather conditions for airports along his route, all of which reported visual meteorological conditions. The night sky was clear during his preflight inspection. After performing a maximum performance takeoff and reaching approximately 65 feet above ground level, he encountered a thick layer of fog that had moved in during the 7-10 minute warm-up period. The pilot lost all visual reference to the surrounding area.

Pilot Actions

Determining that he could maintain the helicopter in a level attitude, the pilot decided to continue the ascent in an attempt to climb above the fog. A few seconds after initiating the ascent, the helicopter impacted the top of a cedar tree. The pilot then initiated an emergency descent, during which the helicopter sustained substantial damage after impacting terrain and rolling over onto its left side.

Mechanical Status

The pilot reported no preimpact mechanical malfunctions or failures with the helicopter that would have precluded normal operation.

Contributing factors

Causes

Pilot

Other contributing factors

Contributed to outcomeTree(s)