WPR18LA189

NTSB accident investigation · Grumman G164B · Colusa, CA · July 9, 2018

Accident · No injuriesClass 3 · LimitedFinal report
Date
July 9, 2018, 11:00 local (18:00 UTC)
Place
Colusa, CA
Injuries
1 uninjured
Damage
Substantial damage
Phase of flight
Maneuvering
Aircraft
N6696KGrumman G164B
Defining event
Maneuvering-low-alt flying: Loss of engine power (total)
Weather
Visual (VMC) · Day
Status
Completed
Report
Approved by Office Director
Investigation class
Class 3
NTSB office
Western Pacific Region
Parties
Federal Aviation Administration
FAA report
20180709015899A
Case key
97719

From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.

On this page

Probable cause

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

Findings · 2

NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings. Under each, the cases with the same finding.

Not determinedNot determined › Not determined · Unknown/Not determinedGrumman Acft ENG Cor-Schweizer G-164B: 11 casesAll aircraft: 2,247 cases
Engine (reciprocating)Aircraft › Aircraft power plant · Unknown/Not determinedGrumman Acft ENG Cor-Schweizer G-164B: 2 casesAll aircraft: 497 casesProbable cause

Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident. Under each, the cases with the same event anywhere in their sequence.

Analysis

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.

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.

Aircraft

Registration
N6696K
Reported as
Grumman G164B
Category
Airplane
Serial number
426B
Built
1978
Airframe hours
9,081
Engine
Pratt and Whitney R1340 SERIES, 600 horsepower, reciprocating
Damage
Substantial damage
Flight
Aerial application · Part 137
Operator
Valley Air Service Ltd
Registered owner
Valley Air Service Ltd
Airworthiness certificate
Special, Restricted (Special)
Last inspection
Annual · December 14, 2017 · 50 hours before
Departed
O08 · Colusa, CA
Equipment
None

Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

Flight crew

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
41
Injuries
None
Certificate
Commercial
Airplane ratings
Single-engine land
Medical
Class 2, Without waivers/limitations
Last flight review
February 26, 2018
Seat
Single
Restraint
3-point
Flight hours
4,380 total · 2,100 in this make and model · 4,207 as pilot in command · 275 in the last 90 days · 75 in the last 30 days · 4 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
190° at 3 knots
Visibility
10 statute miles
Lowest ceiling
None
Temperature
82 °F, dew point 46 °F
Altimeter
30.03 inHg
Observed at
MYV, 20 nm away

Docket · 3

The files NTSB released with the investigation on June 2, 2021, on NTSB’s docket system: statements, records, photos and specialists’ reports. 20.5 MB in all.

FAA reports on this event · 1

The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.