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Atlas / NTSB / WPR18LA189

NTSB CAROL · Event

Event WPR18LA189

2018-07-09 Colusa, California, United States None 1 aircraft Status: Completed

Registry · N6696K

FAA Aircraft Registry record.

Make / Model

GRUMMAN ACFT ENG COR-SCHWEIZER G-164B

Year of manufacture

1978 · 40 years old at event

Engine

P&W R1340 SERIES (600 hp)

Seats / Engines

1 seats · 1 engine

Last airworthiness date

19780615

ADS-B equipped

Yes — Mode-S A8D8DC

Registrant of record

VALLEY AIR SERVICE LTD

Source: FAA Aircraft Registry (releasable master file).

Aircraft involved

Probable cause & findings

Total loss of engine power for reasons that could not be determined based on the available information.

Factual narrative

On July 9, 2018, about 1100 Pacific daylight time, a Grumman G-164B airplane, N6696K, was substantially damaged when it was involved in an accident near Colusa, California. The commercial pilot was not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 137 aerial application flight. The pilot reported that he was approaching a field to begin the application when the engine made a popping noise and started to vibrate. The airplane slowed and the pilot initiated a turn toward a nearby runway. Since the airplane was still losing speed, the pilot added power, but the vibration increased until the engine lost total power. The airplane impacted terrain and came to rest upside down, resulting in substantial damage to the wings and empennage. The operator reported that the engine was sent to a repair and overhaul facility following the accident. No anomalies were found with the engine that would have precluded normal operation. The pilot was performing an aerial application flight when the engine made a popping noise and began to vibrate. The airplane slowed and the pilot initiated a turn toward a nearby runway. The engine subsequently lost total power and the airplane impacted terrain, where it nosed over and came to rest inverted, resulting in substantial damage. The operator reported that the engine was sent to a repair and overhaul facility following the accident and that no anomalies were found that would have precluded normal operation. Source: NTSB Aviation Accident Database Retrieved: 2026-02-12

NTSB Findings

Hierarchical cause / factor breakdown from the FAA bulk avdata database. Each finding tagged C (Cause) or F (Factor).

  • Not determined-Not determined-(general)-(general)-Unknown/Not determined
  • Aircraft-Aircraft power plant-Engine (reciprocating)-(general)-Unknown/Not determined

Verbatim from NTSB's published report. Source file NTSB_2018_WPR18LA189.txt. Findings + structured fields enriched from FAA avall.mdb. Full investigation docket on data.ntsb.gov ↗.