Grumman G164 N3630D

Summary

On 5 May 2019 at about 17:06 local time, a Grumman G164 registered N3630D, operated by Anderson's Flying Service, was involved in an accident near Sutter, California, United States. One person was on board and nobody was injured. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

5 May 2019 at 17:06

Classification

Accident

Location

Sutter, California, United States

Coordinates

39.1894, -121.7086

Aircraft

Grumman G164

Registration

N3630D

Category

Airplane

Year built

1984

Engines

1

Operator

Anderson's Flying Service

Operating rule

Part 137: Agricultural

Purpose of flight

Aerial Application

Phase of flight

Not recorded

Route

Robbins → Robbins

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

WPR19LA137

Nobody was injured.

A loss of engine power due to the in-flight separation of the fuel control unit interconnect rod for reasons that could not be determined due to lack of available evidence.

Quoted verbatim from the NTSB record. This site does not paraphrase or interpret it.

Read the full NTSB narrative

Shortly after the pilot transitioned from climb to cruise flight, the engine power suddenly decreased to idle power without any control inputs from the pilot. He attempted to cycle the throttle to restore power but was unsuccessful. The pilot jettisoned the fertilizer payload he was carrying and initiated a forced landing to a nearby dirt road. The airplane impacted the ground short of the road and collided with trees before it came to rest, substantially damaging the wings and fuselage. The engine continued to run at idle power after the airplane came to rest. Examination of the airplane found that an interconnect linkage between the fuel control unit (FCU) and propeller governor had separated from its mount and the bolt, nut, spacer and cotter pin normally used to secure the FCU interconnect rod to the FCU actuating lever were missing. Additionally, the cam designed to adjust the FCU and propeller governor conditions simultaneously through cockpit control inputs had fractured. This fracture was the result of overstress and likely occurred after the interconnect linkage separated. Based on the design of the FCU, it is likely that the loss of power occurred when the FCU interconnect linkage disconnected in flight, which caused the FCU to revert to its idle power condition. The engine examination revealed no further anomalies, and the pilot reported that the engine continued to function on idle power after the airplane came to rest. As maintenance records indicated that the FCU intermediate linkage had recently been removed, it is likely that maintenance personnel disconnected the interconnect rod for easier access to the FCU. However, as the securing hardware was not recovered, the actual circumstances that led to the separation of the bolt, nut, and washer from the FCU could not be determined. 

Quoted verbatim from the NTSB record.