NTSB Factual Report

HISTORY OF FLIGHT

On October 10, 2001, about 1800 Pacific daylight time, an experimental Zivko Edge 540, N541TW, collided with trees while maneuvering near San Juan Capistrano, California. The pilot/owner was operating the airplane under the provisions of 14 CFR Part 91. The commercial pilot sustained fatal injuries; the airplane was destroyed. The local personal flight departed John Wayne Airport (SNA), Santa Ana, California, at 1748, for the local area flight. Visual meteorological conditions prevailed, and no flight plan had been filed. The primary wreckage was at 33 degrees 32 minutes north latitude and 117 degrees 36 minutes west longitude.

The pilot was going to perform at an airshow the following day. He was going to practice his aerobatic routine on this flight.

PERSONNEL INFORMATION

A review of Federal Aviation Administration (FAA) airman records revealed that the pilot held a commercial pilot certificate with ratings for airplane single engine land and instrument.

The pilot held a second-class medical certificate issued on September 28, 2000. It had the limitations that the pilot must wear corrective lenses, and restricted him from night flying or by color signal control.

No personal flight records were located for the pilot and the National Transportation Safety Board investigator-in-charge obtained the aeronautical experience listed in this report from a review of the airmen FAA records on file in the Airman and Medical Records Center located in Oklahoma City, Oklahoma. The records indicated that as of a medical examination on September 28, 2000, the pilot had a total time of 3,700 hours.

AIRCRAFT INFORMATION

The Zivko Edge 540 experimental airplane, serial number 0017, was commonly used for aerobatics. A review of the airplane's logbooks revealed a total airframe time of 567 hours at the last inspection. An inspection in accordance with the scope and detail of Appendix "D" of 14 CFR Part 43 was completed on March 11, 2001.

The engine was a Textron Lycoming AEIO-540 engine, serial number L-12340-96. Total time on the engine at the last inspection was 567 hours.

METEOROLOGICAL CONDITIONS

The closest official weather observation station was John Wayne Airport (SNA), Santa Ana, California, which was located about 17 nautical miles (nm) northwest of the accident site. The elevation of the weather observation station was 53 feet mean sea level (msl). A routine aviation weather report (METAR) for John Wayne was issued at 1753. It stated: skies 20,000 feet scattered; visibility 6 miles; winds from 230 degrees at 5 knots; temperature 20 degrees Fahrenheit; dew point 16 degrees Fahrenheit; and altimeter 29.97 inHg.

WRECKAGE AND IMPACT INFORMATION

The accident site was in grass covered rolling hills interspersed with clusters of oak trees. The main wreckage was on top of one hill in open terrain. The most distant pieces were 3,000 feet away on top of another hill. These pieces were at the base of a tree, and surrounded by broken branches.

The Federal Aviation Administration (FAA) accident coordinator inspected the wreckage on scene and described his observations. He opined that the airplane hit the ground in a near vertical descent. The wings were oriented on an east-to-west line. The top on the airplane was facing towards the north. The main wreckage was within a 40- to 50-foot circle. The engine was buried in the hard pack soil up to the rear of the engine. The propeller was not visible.

The pilot was outside of the cockpit, and away from the main wreckage. He was wearing a parachute. It was still folded in the pack; however, some shroud lines had snagged on the engine. The pilot also wore a helmet.

The recovery team located the canopy about 800 feet east of the main wreckage. Half of the canopy frame was in a tree; the other half was on the ground below. Shards of Plexiglas remained in the frame pieces.

The left aileron was missing. The left outboard aileron hinge was connected to the wing with two bolts, and it remained with the main wreckage. It fractured along a 45-degree angle through the aft bolthole. The fractured area bent outward and down, and twisted clockwise. The manufacturer's representative reported that normal aileron travel was plus and minus 25 degrees. Investigators observed a gouge in the upper skin of the aileron in the outboard hinge attachment area. Investigators rotated the hinge, and it fit into the gouge at an angle of 95 degrees aileron up deflection.

As constructed, two metal plates sandwiched both the inner and middle hinges. Three rivets secured the plates to the hinges and four bolts connected the plates to the aft spar. All three rivets for both hinges sheared flush with their respective metal plate's surfaces. The outboard plate for the inner hinge bent outboard, and the bottom wing skin was gouged in an outboard direction. The top wing skin in this area was gouged in an inboard direction. The middle hinge's attachment plates and wing skin area did not appear deformed.

The left aileron's control rod was in the main wreckage. One adjustable rod end and its threaded section separated from the control rod and remained attached to the wing's bellcrank. The fracture surface at the end of the threaded area was cone shaped and had a matte surface. The control rod buckled, and bent upward at a point that approximated the trailing edge of the wing. The threaded rod end at the aileron attachment point bent up. Threads aft of the pal nut appeared undamaged; threads forward of the pal nut appeared damaged.

Several days after recovery of the main wreckage, friends of the pilot found the outboard half of the left aileron about 3,000 feet east of the main wreckage, near broken branches at the base of a tree. The outboard half of the left aileron separated a few inches outboard of the middle hinge. This half had dirt and a few scratches along the tip, which contained the counterweight. Located near the outboard aileron were the transponder antenna, the left side windows, and the left aileron spade arm. The transponder antenna had been installed on the bottom of the airplane and forward of the aileron. According to the manufacturer, the airplane was fully controllable with one aileron missing.

The left aileron's top skin exhibited a fracture surface along a 45-degree angle from leading edge to trailing edge and inboard to outboard.

MEDICAL AND PATHOLOGICAL INFORMATION

The Orange County Sheriff-Coroner completed an autopsy. The FAA Toxicology and Accident Research Laboratory performed toxicological testing of specimens of the pilot. The results of analysis of the specimens were negative for carbon monoxide and cyanide.

The report contained the following results: cimetidine in muscle.

The report contained the following results: 77 (mg/dL, mg/hg) ethanol detected in muscle; 3 (mg/dL, mg/hg) acetaldehyde detected in muscle; 3 (mg/dL, mg/hg) N-propanol detected in muscle; 1 (mg/dL, mg/hg) 2-butanol detected in muscle.

NTSB Probable Cause

the pilot's failure to maintain an adequate terrain/object altitude clearance while intentionally performing low level aerobatics, which resulted in a loss of aircraft control.