No fatalities

GRUMMAN ACFT ENG COR-SCHWEIZER G-164B accident at Colusa, CA, 4 Jun 2023

Colusa, CA, United States

On June 4, 2023, a GRUMMAN ACFT ENG COR-SCHWEIZER G-164B operated by Valley Air was involved in an aviation accident near Colusa, CA. No fatalities were reported. Investigators recorded the probable cause as: The pilot’s failure to maintain clearance from a power line during a low-level aerial application flight. Contributing to the accident was the pilot’s fatigue. 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

Probable cause

The pilot’s failure to maintain clearance from a power line during a low-level aerial application flight. Contributing to the accident was the pilot’s fatigue.

— NTSB Determination

Contributing factors

PilotCompliance w/ procedureContributed to outcome

Frequently asked questions

What happened in the 4 Jun 2023 GRUMMAN ACFT ENG COR-SCHWEIZER G-164B accident near Colusa, CA?

The pilot’s failure to maintain clearance from a power line during a low-level aerial application flight. Contributing to the accident was the pilot’s fatigue.

Were there any fatalities in the 4 Jun 2023 GRUMMAN ACFT ENG COR-SCHWEIZER G-164B accident?

No fatalities were recorded in this accident.

What aircraft was involved and where did it happen?

The accident on 4 Jun 2023 involved a GRUMMAN ACFT ENG COR-SCHWEIZER G-164B, operated by Valley Air, at Colusa, CA.

What was the probable cause of the accident?

The pilot’s failure to maintain clearance from a power line during a low-level aerial application flight. Contributing to the accident was the pilot’s fatigue.