CEN11LA556

NTSB accident investigation · Grumman G-164A · El Campo, TX · August 18, 2011

Accident · No injuriesLimited investigationFinal report
Date
August 18, 2011, 09:36 local (14:36 UTC)
Place
El Campo, TX
Injuries
1 uninjured
Damage
Substantial damage
Phase of flight
Initial climb
Aircraft
N6567Grumman G-164A
Defining event
Initial climb: Loss of engine power (total)
Weather
Visual (VMC) · Day
Status
Completed · report November 22, 2011
Report
Approved by Office Director
NTSB office
Central Region
Parties
FAA Flight Standards District Office
FAA report
20110818017739A
Case key
81431

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

Separation of the No. 3 cylinder exhaust valve rocker arm, which resulted in a loss of engine power.

Findings · 1

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.

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 about 2 miles from the departure airstrip when the engine lost power. The pilot began to dump the fertilizer load and landed straight ahead in a flooded rice field. Upon touchdown, the airplane nosed over, resulting in substantial damage to the airplane. Examination of the engine revealed a crack radiating from the exhaust valve rocker box on the No. 3 cylinder, where the rocker arm bolt attaches to the rocker arm. The top of the rocker box separated, causing the rocker arm to fail.

Factual narrative

On August 18, 2011, at 0936 central daylight time, a Grumman G-164A, N6567, registered to and operated by Aero Ag Services, Inc., impacted a rice field shortly after taking off from a grass airstrip near El Campo, Texas. The commercial pilot was not injured. The airplane sustained substantial damage to its top wing, vertical stabilizer, and rudder. The airplane was being operated under the provisions of 14 Code of Federal Regulations Part 137 as an aerial application flight. Visual meteorological conditions prevailed for the flight, which was operating without a flight plan. The local flight originated from El Campo moments before the accident. According to the pilot-operator's accident report, he had just taken off and was about 2 miles from the airstrip when the engine lost power. The pilot started dumping his fertilizer load and landed straight ahead in a flooded rice field. Upon touchdown, the airplane nosed over. Post-accident examination revealed a crack radiating from the exhaust valve rocker box on the number 3 cylinder where the rocker arm bolt attaches the rocker arm. The top of the rocker box separated, causing the rocker arm to fail. An examination of the remaining systems revealed no preimpact failures or anomalies.

Aircraft

Registration
N6567
Reported as
Grumman G-164A
Category
Airplane
Serial number
706
Airframe hours
12,691
Engine
P&W R-1340-AN1, 600 horsepower, reciprocating
Damage
Substantial damage
Flight
Aerial application · Part 137
Operator
Aero Ag Services Inc
Registered owner
Aero Ag Services Inc
Airworthiness certificate
Special, Restricted (Special); Special, Experimental light sport (Special)
Last inspection
Annual · July 28, 2011 · 66 hours before
Departed
NONE · Garwood, TX
Destination
NONE · El Campo, TX

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
55
Injuries
None
Certificate
Commercial
Airplane ratings
Single-engine land
Medical
Class 2, With waivers/limitations
Last flight review
February 11, 2011
Seat
Front
Flight hours
22,250 total · 21,000 in this make and model · 225 in the last 90 days · 80 in the last 30 days · 4 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
200° at 2 knots
Visibility
15 statute miles
Lowest ceiling
None
Temperature
90 °F

Docket · 3

The files NTSB released with the investigation on October 4, 2011, on NTSB’s docket system: statements, records, photos and specialists’ reports. 1.8 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.

Other investigations on N6567 · 3

Matched to the same aircraft by N-number and date.