NTSB Factual Report

HISTORY OF FLIGHT

On July 15, 2004, about 0819 mountain daylight time, a Piper PA-23-160, (Apache) N4439P, was destroyed when it collided with terrain approximately two miles from the Ontario Municipal Airport, Ontario, Oregon. The airplane was owned by the second pilot, and was being operated as a visual flight rules (VFR) instructional flight under the provisions of Title 14, CFR Part 91, when the accident occurred. The first pilot, a certified flight instructor (CFI), and the second pilot, a certified commercial pilot working toward a multi engine rating, were fatally injured. No flight plan had been filed for the flight that originated from Ontario, approximately 1 hour and 20 minutes prior to the accident.

Witnesses reported that they observed the airplane traveling toward the airport from the southeast in a level flight attitude. A witness stated the airplane was traveling slowly "as if on a landing procedure." The witness stated that shortly thereafter the airplane appeared to "auger" toward the ground in a left wing low attitude. The witness reported that the airplane made approximately three revolutions before impacting the terrain in a nose low attitude.

The second pilot had recently purchased the airplane and was utilizing it to complete his multi-engine rating/training. Logbook records indicated this was his third instructional flight in the airplane. All of the instructional flights were completed with the first pilot.

The pilots departed Ontario on the morning of the accident and proceeded to Boise, Idaho, (Gowen Field) to complete practice instrument approaches.

The airplane was returning to Ontario when the accident occurred.

PILOT INFORMATION

The first pilot held a commercial pilot certificate with airplane single-engine land, multi-engine land and instrument airplane ratings. In addition to the commercial certificate, the pilot held a T33 type rating and a certified flight instructor certificate with ratings for airplane single-engine land, multi-engine land, and instrument airplane.

The first pilot's most recent FAA second-class medical certificate was issued on September 16, 2003, and contained a limitation requiring the pilot to possess glasses for near and intermediate vision.

No personal flight records were located for the first pilot and the aeronautical experience listed in this report was obtained from a review of the FAA medical records on file in the Airman and Medical Records Center located in Oklahoma City, Oklahoma. These records indicated that as of a medical examination on September 16, 2003, the pilot had a total flight time of approximately 6,000 hours with 200 hours logged in the six months preceding the medical examination.

The second pilot held a commercial pilot certificate with airplane single-engine land and instrument airplane ratings. The commercial pilot certificate was issued on May 25, 2004.

The second pilot's most recent FAA second-class medical certificate was issued on March 22, 2004, and contained limitations that the pilot shall wear corrective lenses for vision.

Examination of the second pilot's logbook indicated an estimated total flight time of approximately 705 hours. The pilot logged approximately 24 hours in the 30 days preceding the accident. Two flights in the accident airplane, totaling 3.5 hours, were logged on July 14. These were the pilot's only logged flight hours in the accident airplane.

AIRCRAFT INFORMATION

The accident airplane, a Piper Apache PA-23-160 (serial number 231956) was manufactured in 1956. The four-place light twin was powered by two Textron Lycoming O-320's rated at 160 HP each.

The tachometer for both engines read 3319 at the accident scene.

Maintenance records for the airplane were not located and the information listed in this report was obtained from a review of FAA records and actual observations during the onsite investigation.

METEOROLOGICAL INFORMATION

The closest weather observation facility to the accident site is the Ontario Municipal Airport, approximately 2 miles to the southeast. On July 15, 2004, at 0753 MDT, the hourly Aviation Routine Weather Report (METAR) was, in part, wind from 290 degrees (true) at 3 knots; visibility 10 statute miles; sky conditions clear; temperature 18 degrees C; dew point 8 degrees C; altimeter 30.00 inches.

WRECKAGE AND IMPACT INFORMATION

Personnel from the National Transportation Safety Board, Federal Aviation Administration, Lycoming and Piper accessed the wreckage site on July 15-16, 2004.

The wreckage was located on level terrain near the center of a 16-acre mature onion field at 43 degrees 59 minutes' north latitude, and 117 degrees .096 minutes' west longitude. The wreckage site elevation was approximately 2,190 feet above mean sea level. The wreckage came to rest approximately two miles southeast of the Ontario airport.

The airplane came to rest oriented on a northerly heading, in the upright position. The forward section of the airplane, from mid cabin forward, sustained extensive impact related damage. The aft cabin area and empennage remained attached to the main wreckage. Damage was noted longitudinally along the aft section of the fuselage. Extensive damage was noted to the entire wing assembly.

The cockpit controls and instrument panel sustained extensive impact damage and a majority of the navigation instrumentation was destroyed. The navigation and communication radios, and associated wiring harnesses, were heavily damaged and displaced from the installed positions. The emergency hydraulic pump handle was observed in the full aft (extended) position. The mixture controls, throttles and propeller controls were observed in the full forward position. The right fuel control valve was selected to the right main fuel tank. The left fuel control valve was selected to the left main fuel tank position. The fuel cross feed was in the "off" position and both engine primers were in and locked.

The right wing separated from the fuselage near the wing root. The wing was resting, leading edge down, against the fuselage. Extensive impact related leading edge deformation was noted to the entire span of the wing assembly. The landing gear remained attached to the assembly and was in the down position. The aileron and wing flap were found attached to their respective mounting points on the wing assembly. The right engine mounting system, engine and propeller assembly were attached to the wing and sustained extensive impact related damage. The propeller assembly and forward section of the engine were partially buried in the soft mud, adjacent to the airplane wreckage.

The inboard section of the left wing remained partially attached to the fuselage. The aileron was still attached to the wing section. The outboard section of the wing, from the engine nacelle outboard, had separated from the main wing assembly and was located within the confines of the debris field. The flap assembly separated from the inboard section of wing and was located behind the wing. The landing gear remained attached to the wing section and sustained extensive impact related damage. Extensive aft crushing and leading edge damage was noted to the entire assembly.

Minimal damage was noted to the empennage and associated control surfaces. All fixed and movable control surfaces remained attached in their respective positions and the control cables were present.

All aircraft components were located in the immediate area of the main wreckage.

MEDICAL AND PATHOLOGICAL INFORMATION

An autopsy on the first pilot was conducted by the Ada County Coroner's Office on July 16. According to the autopsy report, the first pilot's cause of death was attributed to blunt force trauma. The manner of death was listed as accidental.

The FAA Bioaeronautical Sciences Research Laboratory, Oklahoma City, Oklahoma, performed toxicological testing of specimens of the first pilot. According to the postmortem toxicology report, results were negative for carbon monoxide, cyanide, ethanol and controlled substances. See attached report for test parameters.

An autopsy on the second pilot was conducted under the direction of the State of Oregon Medical Examiner's Office on July 16. According to the autopsy report, the second pilot's cause of death was attributed to massive blunt force chest and head trauma.

The FAA Bioaeronautical Sciences Research Laboratory, Oklahoma City, Oklahoma, performed toxicological testing of specimens of the first pilot. According to the postmortem toxicology report, results were negative for carbon monoxide, cyanide, ethanol and controlled substances. See attached report for test parameters.

TESTS AND RESEARCH

On September 8, 2004, representatives from the National Transportation Safety Board, Piper and Lycoming examined the wreckage at a facility in Ontario, Oregon.

The left engine was found attached to the engine mount assembly and firewall. Impact related damage was noted to the engine assembly and associated engine mounts. Rocker arm, valve train and accessory gear continuity was established by rotating the engine's crankshaft by hand. All four cylinders developed pressure when the crankshaft was manually rotated. Internal examination of the piston cylinders, utilizing a lighted bore scope, revealed no evidence of a mechanical malfunction. The top spark plugs were removed and visually inspected. All four sparkplugs were consistent in color and displayed even wear. Both magnetos were removed to facilitate the inspection. Both magneto drive mechanisms were intact and undamaged. The magnetos from the left engine both produced spark when manually rotated.

The left engine carburetor sustained impact related damage. The carburetor was removed from the wreckage and disassembled. The fuel bowl was free of contaminants and the float assembly was secure and undamaged.

The left engine fuel pump was observed attached to the engine at its respective mounting pad. Disassembly of the pump revealed no evidence of a mechanical malfunction. Residual fluid, consistent with aviation gasoline, was observed within the pump assembly.

The left propeller assembly was found partially attached to the crankshaft flange. The crankshaft flange was bent and displaced. The spinner remained attached to the assembly. Both propeller blades were attached to the hub assembly. Propeller blade "A" was bent aft in a smooth fluid arc. Little damage was noted to the opposing propeller blade ("B").

The right engine was found attached to the engine mount assembly and firewall. Impact related damage was noted to the engine assembly and associated engine mounts. Rocker arm, valve train and accessory gear continuity was established by rotating the engine's crankshaft by hand. All four cylinders developed pressure when the crankshaft was manually rotated. Internal examination of the piston cylinders, utilizing a lighted bore scope, revealed no evidence of a mechanical malfunction. The top spark plugs were removed and visually inspected. All four sparkplugs were consistent in color and displayed even wear. Both magnetos were removed to facilitate the inspection. Both magneto drive mechanisms were intact and undamaged. The magnetos from the right engine both produced spark when manually rotated.

The right engine carburetor sustained impact related damage. The carburetor was removed from the wreckage and disassembled. The fuel bowl was free of contaminants and the float assembly was secure and undamaged.

The right engine fuel pump was observed attached to the engine at its respective mounting pad. Disassembly of the pump revealed no evidence of a mechanical malfunction. Residual fluid, consistent with aviation gasoline, was observed within the pump assembly.

The right propeller assembly remained attached to the crankshaft flange. Impact related damage (bending) was noted to the flange. The spinner remained attached to the assembly. Both propeller blades were attached to the hub assembly. Propeller blade "A" was bent aft in a smooth fluid arc with little damage noted to the leading edge of the blade. Leading edge damage, chord wise striations and "S" bending was noted to propeller blade "B".

ADDITIONAL INFORMATION

On February 28, 2005, the airplane, engines and associated components were released to CTC Services, Renton, Washington.

NTSB Probable Cause

The pilot's failure to maintain airspeed resulting in an aerodynamic stall while maneuvering for an approach to land.