Accident Details
On April 15, 2008, at about 1600 Pacific daylight time, a Cessna 150L, registration N1364Q, was substantially damaged when it impacted terrain following a loss of control during the takeoff initial climb from runway 29 at Columbia Airport (O22), Columbia, California. The flight instructor received minor injuries, and the student pilot was not injured. The airplane was operated by the student pilot as a 14 Code of Federal Regulations Part 91 instructional flight. Visual meteorological conditions prevailed, no flight plan was filed, and the flight was originating at the time of the accident.
According to a written statement from the flight instructor, the student pilot had recently purchased the airplane, and the purpose of the accident flight was to test fly it within the traffic pattern and land before planning a return flight to Idaho. Before departure, the instructor performed an engine runup and noted that the wind was from 300 degrees at 10 knots gusting to 15 knots, favoring runway 29, a 2,600-foot-long turf runway. Prior to initiating a short field takeoff, he held the brakes, selected 10 degrees of flaps, and applied full power, observing that the engine produced only 2,050 rpm. The instructor expected the rpm to increase upon releasing the brakes.
During the takeoff roll, the instructor felt that tall grass slowed the airplane's acceleration before it lifted off at 55 miles per hour. He lowered the nose to gain airspeed in ground effect, but the airplane was not accelerating. Due to upward sloping terrain with trees and power lines in the flight path, he turned left to avoid obstacles. During the turn, wind got under the airplane's right wing, steepening the bank. Subsequently, the airplane stalled, entered a spin to the left, and impacted the ground in a nose-low attitude, resulting in structural damage to the fuselage and both wings.
Aircraft Examination
On April 22, 2008, representatives from Teledyne Continental Motors and Cessna Aircraft, under the supervision of an FAA inspector, examined the airframe and engine. No anomalies were found with the airframe. The engine was separated from the airframe, with all accessories still attached. Continuity was established throughout the engine and valve train when the crankshaft was rotated by hand. Thumb compression was obtained on all four cylinders.
The top and bottom spark plugs were examined and showed worn-out normal wear signatures when compared to the Champion Check-A-Plug comparison chart. The top and bottom number one, three, four, and top number two spark plugs exhibited dark gray deposits within the electrode area. The bottom number two spark plug had an oily residue. A carbon-based substance bridged the gap between the ground and center electrodes on both top and bottom number two cylinder spark plugs.
Examination of the magnetos revealed that the right magneto ignition harness leads were connected to the upper number two and four cylinder positions and the bottom number one and three cylinder positions. The left magneto ignition harness was connected to the upper number one and three cylinder positions and the bottom number two and four cylinder positions, which is the reverse of the manufacturer's recommended connections. The right magneto driveshaft rotated freely with impulse coupling engagement and produced spark on three of four terminals. The left magneto driveshaft rotated freely with impulse coupling engagement and produced spark on all four terminals. The magnetos were removed and examined. The right magneto efficiency gap (E-gap) was measured at 10 degrees with a breaker point gap of 0.015 inches. The left magneto E-gap was measured at 21 degrees with a breaker point gap of 0.008 inches. The manufacturer specifies an E-gap of 10 degrees and a breaker point gap of 0.018 inches. No additional engine anomalies were noted.
Maintenance History
Review of maintenance records showed that the airplane underwent its most recent annual inspection on December 14, 2007, at a total airframe time of 5,007.7 hours and an engine time since major overhaul (SMOH) of 440.7 hours. The most recent maintenance was an alternator removal and replacement on April 5, 2008, at an engine time SMOH of 441.2 hours. At the time of the accident, the airframe and engine had accumulated 0.8 hours since the last annual inspection.
Engine Power Check Guidance
The owner's manual for a 1971 Cessna 150 states under Take-Off, subheading Power Checks: 'It is important to check full-throttle engine operation early in the takeoff run. Any signs of rough engine operation or sluggish engine acceleration is good cause for discontinuing take-off. If this occurs, you are justified in making a thorough full-throttle, static runup before another take-off is attempted. The engine should run smoothly and turn approximately 2,500 to 2,600 RPM with carburetor heat off.'