CEN10LA559

NTSB accident investigation · Beech A36TC · Snook, TX · September 26, 2010

Accident · No injuriesLimited investigationFinal report
Date
September 26, 2010, 17:00 local (22:00 UTC)
Place
Snook, TX
Injuries
1 uninjured
Damage
Substantial damage
Phase of flight
Takeoff
Aircraft
N468SGBeech A36TC
Defining event
Takeoff: Collision during takeoff/land
Weather
Visual (VMC) · Day
Status
Completed · report May 16, 2011
Report
Approved by Office Director
NTSB office
Central Region
Parties
FAA Flight Standards District Office
FAA report
20100926050269A
Case key
77399

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

The pilot's failure to recognize the change in wind velocity and his decision to make a downwind takeoff from the grass airstrip, which led to the airplane's degraded climb capability.

Findings · 5

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.

Wind: tailwindEnvironmental issues › Conditions/weather/phenomena · Contributed to outcomeBeech A36TC: 2 casesAll aircraft: 594 cases
Wind: gustsEnvironmental issues › Conditions/weather/phenomena · Contributed to outcomeBeech A36TC: 1 caseAll aircraft: 1,199 cases
Aircraft capability: climb capabilityAircraft › Aircraft oper/perf/capability · Attain/maintain not possibleBeech A36TC: 1 caseAll aircraft: 183 casesProbable cause
Object/animal/substance: fence/fence postEnvironmental issues › Physical environment · Contributed to outcomeBeech A36TC: 1 caseAll aircraft: 313 cases

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

According to the pilot, the wind had been from the north between 5 and 10 knots for most of the afternoon. He elected to make a downhill takeoff, and as the airplane neared the end of the runway it failed to gain sufficient airspeed to become airborne. The airplane continued off the runway and struck a pipe and then a fence, resulting in substantial damage to the fuselage and wing. Upon exiting the airplane, the pilot estimated that the wind had increased to 25 knots. The pilot stated there were no preimpact mechanical malfunctions or anomalies with the airplane.

Factual narrative

On September 26,2010, approximately 1700 central daylight time, a Beech A36TC, N468SG, registered to and operated by the pilot, was substantially damaged when it struck a barbed wire fence and impacted an open field during takeoff from a grass airstrip 1 mile west of Snook, Texas. Visual meteorological conditions (VMC) prevailed at the time of the accident. The personal flight was being conducted under the provisions of 14 Code of Federal Regulations (CFR) Part 91 without a flight plan. The pilot, the sole occupant on board the airplane, was not injured. The cross-country flight was originating at the time of the accident, and was en route to Austin (3R9), Texas. According to the pilot's accident report, the wind had been out of the north between 5 and 10 knots for most of the afternoon. A cold front had recently passed through the area. He boarded the airplane and, unbeknownst to him, wind velocity increased to about 20 knots. The pilot elected to make a down hill takeoff. The pilot wrote, "About 3/4 way down the strip, I realized the airplane was not light on the controls and was not ready to fly. I noted the IAS was 60 knots and I kept the plane on the ground until reaching the end of the strip. I climbed up and over a barbed wire fence and crossed a deep creek. I then flew up and over a hill, but on the back side of the hill I lost lift and descended slightly. More fences and a road with ditches were coming up, so I climbed again. There was a 6-inch diameter pipe with a phone box mounted on it extending up about five feet above the fence on the near side of the road. The pipe cut off my left tip tank and the outboard portion of my left wing. After crossing the road and ditches, I struck a fence on the far side of the road and settled in a cow pasture. I went through another barbed wire fence and the rough ground in the pasture created side loads on my main gear, causing it to collapse inwards into the wells. The plane stopped and I shut the engine down normally. The nose gear remained extended and the only prop strikes were those on the fence wire." Upon exiting the airplane, the pilot estimated the wind had increased to 25 knots. The pilot said he had flown in and out of the airstrip for forty years without incident. He said the dry, freshly-mowed airstrip dropped 20 feet from the northwest to southeast. He had never installed a windsock because he was familiar with the terrain and varying wind conditions. He hadn't expected "the secondary wind gust that suddenly developed late that afternoon. A windsock is the only way I could have known about the changing wind speed."

Aircraft

Registration
N468SG
Reported as
Beech A36TC
Category
Airplane
Serial number
EA-147
Airframe hours
3,764
Engine
Continental TSIO-520-UB, 300 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Operator
Guy E.Knolle, Jr.
Registered owner
Guy E.Knolle, Jr.
Airworthiness certificate
Standard, Normal
Last inspection
Annual · March 10, 2010 · 63 hours before
Departed
NONE · Snook, TX
Destination
3R9 · Austin, TX
Airport
NONE · Private Airstrip, runway 15, 2,500 × 25 ft, grass/turf

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
74
Injuries
None
Certificate
Private
Airplane ratings
Single-engine land, Multi-engine land
Instrument ratings
Airplane
Medical
Class 3, Without waivers/limitations
Last flight review
December 1, 2009
Seat
Left
Flight hours
8,000 total · 1,000 in this make and model · 9 in the last 90 days

Weather

Conditions
Visual (VMC) · Day
Wind
340° at 14 knots, gusting 21
Visibility
10 statute miles
Lowest ceiling
5,500 ft broken
Temperature
82 °F, dew point 70 °F
Altimeter
29.87 inHg
Observed at
CLL, 15 nm away

Docket · 2

The files NTSB released with the investigation on January 19, 2011, on NTSB’s docket system: statements, records, photos and specialists’ reports. 192 KB 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.