NTSB Factual Report

HISTORY OF FLIGHT

On December 4, 2003, at 0854 Pacific standard time, a Wing Aircraft, D-1, N8602J, collided with desert terrain while maneuvering about 11 nautical miles (nm) west-southwest of Rosamond, California. The National Test Pilot School (NTPS), located in Mojave, California, operated the airplane under the provisions of 14 CFR Part 91. The multiengine airplane was destroyed by impact forces. The airline transport pilot, who was acting as a flight instructor, and the student were fatally injured. Visual meteorological conditions prevailed, and a company flight plan was in effect. The instructional familiarization flight originated from runway 26 at the Mojave Airport, approximately 0832.

Prior to initiating the accident flight, the instructor briefed the student using a lesson plan. The specific stall and Vmc maneuvers to be performed were listed on a document, which the NTPS termed a "flight card." The anticipated length of the familiarization flight was 1 hour.

Recorded radar data indicates that the Mode C (altitude encoding) transponder equipped airplane departed from the Mojave Airport in a westerly direction. Thereafter, the airplane proceeded in a southwesterly direction and flew toward the area where the accident was to occur, with a ground speed between 100 and 140 knots. No altitude data was recorded by radar until about 0846, at which time the airplane's altitude indicated 6,000 feet. At 0849, after reversing course, the airplane's altitude decreased from 5,900 feet to 5,200 feet, with a groundspeed of about 80 knots. Thereafter, the airplane regained altitude. About 0850, the airplane's altitude decreased from 6,000 feet to 5,600 feet, with a ground speed of 80 knots within a matter a seconds. At 0853:20, the airplane's altitude indicated 5,900 feet. The airplane's position remained relatively constant on the radarscope during the final seconds of its recorded flight. At 0853:49, the altitude indicated 3,500 feet, and the groundspeed decreased to 60 knots, where it remained until the target disappeared from radar at 0853:54, at an altitude of 3,100 feet. The estimated location of the airplane when last observed on radar was about 34 degrees 50.600 minutes north latitude by 118 degrees 23.383 minutes west longitude. During the last 5 seconds of the radar track, the target depicted a left turn.

PERSONNEL INFORMATION

Instructor.

A review of Federal Aviation Administration (FAA) airman records revealed the instructor held an airline transport pilot certificate with an airplane single engine rating. He also held a commercial pilot certificate with a multiengine land rating. His second-class medical certificate was issued on January 9, 2003. It had the limitations that the pilot must wear corrective lenses for near and distant vision. An examination of the instructor's logbook indicated he had accumulated an estimated 1,711 hours of civilian flight time. He had logged 52.2 hours in the last 90 days, and 18.9 in the last 30 days. He had an estimated 122 hours in the accident make and model airplane, with 27.4 hours over the past year. His total multiengine flight time was approximately 387 hours. NTPS management reported that the instructor was current in the accident airplane and authorized to provide the familiarization flight to the student.

The instructor was a graduate of the United States Air Force test pilot school. He served as the Director of Flight Operations, and as the Flying Safety Officer for the NTPS. He had an estimated total flying time of 5,767 hours. The majority of the instructor's flight time was in an F-4 (2,700 hours). The instructor had 400 hours of flight time in an E-8A/C (a modified Boeing 707). He had 1,600 hours of flight time as an instructor pilot in F-4 aircraft, 75 hours in an F-16, and 50 hours in other aircraft.

Student.

The student was a pilot for the Korean Air Force. He did not hold any FAA airman certificates; however, he was rated as an instructor pilot by the Korean Air Force. He maintained both F16 and instrument flying authorizations.

Based on flight time records submitted by the Korean Embassy, certified January 8, 2004, the student had an estimated total flying time of 1,531 hours, with 1,237 hours as pilot-in-command. He had been flying for the past 12 years. The majority of his total flight time, approximately 962 hours, was in F16C/D and KF16C/D (the Korean equivalent to the F16) aircraft. Most of his remaining flight time was in F5E/F aircraft (416 hours) and T37C airplanes (122 hours). The flight times submitted by the Korean Embassy did not include NTPS flights.

The NTPS's Deputy Director reported to the National Transportation Safety Board's investigator-in-charge (IIC) that the student was enrolled in the school's 6 week-long pre-Professional Test Pilot course (pre-TPS), in preparation for commencement of the 11-month-long test pilot program. The pre-TPS course provides, in pertinent part, familiarization training in the flight characteristics of the fuel injected, normally aspirated, reciprocating propeller-equipped airplane. The curriculum includes stalls, with the landing gear and wing flaps retracted and extended. The course also exposes the student to various maneuvers including velocity minimum control (Vmc) demonstrations with both the left (critical) engine and the right engine operating at reduced power

The student began his training at the NTPS in October 2003. He was preparing to enter the Professional Pilot course in January 2004. His flight time records at the school indicated that the first two flights were in helicopters, with a total flight time of 2.5 hours on November 17. On December 2, the pilot flew twice in single engine propeller airplanes, accumulating a total flight time of 2.0 hours. On December 3, he made one flight in a multiengine propeller airplane, with a flight time of 1.2 hours, and one flight in a single engine propeller airplane, logging 0.9 hours of flight time.

AIRPLANE INFORMATION

The accident airplane was a Wing D-1, serial number 9. The airplane was manufactured by Derringer. Emerald Enterprises LTD currently holds the type certificate. The Wing D-1 is a low-wing, multiengine airplane, with conventional propellers. A review of the airplane's logbooks revealed a total airframe time of 927.9 hours at the last 100-hour annual inspection. An annual inspection was completed on May 15, 2003. The Hobbs hour meter was placarded inoperative.

The airplane had a Textron Lycoming IO-320-B1C engine, serial number L-5782-55A, installed on the left side. Total time on the engine at the last 100-hour annual inspection was 355.9 hours.

The airplane had a Textron Lycoming IO-320-B1C engine, serial number L-5781-55A, installed on the right side. Total time on the engine at the last 100-hour annual inspection was 355.9 hours.

A review of the airframe, engine, and propeller maintenance records by the Safety Board IIC did not reveal evidence of any anomalies or uncorrected maintenance issues prior to the flight.

Fueling records at the East Kern Airport District established that the airplane was last fueled on December 2, 2003, with the addition of 5.7 gallons of 100LL octane aviation fuel. The flight departed with 60 gallons of fuel on board.

The airplane's approved flight manual (AFM) states that the stall speeds for the airplane are 80 miles per hour (mph) indicated airspeed in the clean configuration, and 72 mph with the gear and flaps extended. Aerobatic maneuvers, including spins, are prohibited. A stall speed chart indicated that the stall speeds increase as the angle of bank increases. The chart specified the following stall airspeeds:

Flaps Up (Power off)

0 degrees Angle of Bank at 80 mph, IAS

15 degrees Angle of Bank 81 mph

30 degrees Angle of Bank 86 mph

45 degrees Angle of Bank 95 mph

60 degrees Angle of Bank 113 mph

Flaps Down (Power off)

0 degrees Angle of Bank at 72 mph, IAS

15 degrees Angle of Bank 73 mph

30 degrees Angle of Bank 77 mph

45 degrees Angle of Bank 86 mph

60 degrees Angle of Bank 102 mph

WRECKAGE AND IMPACT INFORMATION

The Safety Board IIC, an FAA inspector, a Lycoming representative, and a representative from Flight Research, Inc., examined the wreckage at the accident scene on December 5, 2003. The airplane impacted level desert 2,600-foot mean sea level (msl) terrain less than 1/4-mile from the last location at which it was observed on radar. The wreckage was found at the following approximate global positioning satellite coordinates: 34 degrees 50.682 minutes north latitude by 118 degrees 23.299 minutes west longitude. A circular area around the airplane was devoid of vegetation. The wreckage was distributed in an area approximately 65 feet wide and 122 feet long. The nose of the airplane came to rest facing a north-northeasterly direction. Fuselage and cockpit structure was found partially collapsed in a downward direction.

Flight control continuity was established through the aileron, rudder, and elevator control systems, to the cockpit area. The left and right aileron cables were intact to the cockpit area. The right rudder cable displayed "broomstrawing" at its breaking point.

The elevator was controlled through a series of push-pull tubes. The rear push-pull tube was found separated at the belly mounted pivot follower. A 3-inch end section that attached the rear push-pull tube to the follower was not recovered. The attachment to the follower displayed a smeared surface on one side; the other displayed a grainy appearance, broken at a 45-degree angle. A bolt attachment to the forward follower was sheared. The control tube was bowed at the fuel selector location.

No control stop deformation, bending, or over-travel evidence consistent with flight control surface flutter was detected.

The cockpit area was examined. The mixture controls were found in the full-forward position. The propeller controls were in the full-forward position and curled right. The throttle controls were in the aft position. The left and right magnetos' switches were in the both position and clicked when turned to the off position. The landing gear selector was in the down position and displaced slightly right. Both control yokes were in the full aft position and bent downward. The left yoke vertical grip on the right side was not attached. Neither of the right yoke vertical grips were attached.

The flap actuators indicated that the flaps were symmetrically extended in a down position. The elevator trim position indicated neutral. The rudder and aileron trim setting was not determined.

The canopy was found on the left side of the airplane, aft of the left wing, in an inverted position. The latches were found in the deformed fuselage structure with the actuator control rods broken. The canopy seal did not display any over-travel signatures.

The oleo struts on the left and right main landing gear were oriented perpendicular to the fuselage. The wheels were bent aft. The nose gear was deformed back and upward.

The engines and propellers were examined. The left engine crankshaft was rotated. Fuel was present throughout the system. The flow divider was examined, the gaskets were intact, and no perforations or holes were found. The spark plug electrodes were gray in color, which corresponded to normal operation according to the Champion Aviation Check-A-Plug AV-27 Chart. The left propeller remained attached to the left engine. Blade 1 was undamaged. Blade 2 was bent slightly aft. Chordwise striations were found on the cambered surface, and none were found on the face. There was no evidence of leading edge gouging.

The right engine crankshaft was rotated. Fuel was present throughout the system. The flow divider was examined, the gaskets were intact, and no perforations or holes were found. The top spark plug electrodes were dark and sooty, which corresponded to rich operation according to the Champion Aviation Check-A-Plug AV-27 Chart. The bottom spark plugs, excluding cylinder number 4 (which could not be removed), were white in color, which corresponded to lean operation according to the Champion Aviation Check-A-Plug AV-27 Chart. The number 3 and number 4 cylinders were borescoped. Their coloration was consistent with normal operation. The right propeller hub was found detached and forward of the right engine. Blade 1 did not display any torsional deformation. Chordwise striations were found on both the cambered and face side. There was no evidence of leading edge gouging. Blade 2 was undamaged.

Fuel was found in desert soil beneath both wings. Fuel was also detected in the airplane's fuel lines.

METEROLOGICAL INFORMATION

The closest aviation weather observation station to the accident site was at Mojave (MHV), 17 nm northeast of the accident site. The elevation at MHV is 2,791 feet msl. A routine aviation weather report (METAR) for Mojave was issued at 0845. It stated: skies clear; visibility 40 miles; winds calm; temperature 16 degrees Fahrenheit; altimeter 30.20 InHg.

MEDICAL AND PATHOLOGICAL

The Kern County Coroner completed autopsies on the instructor and the student. They also performed toxicological tests which were negative for drugs of abuse and alcohol.

The FAA Toxicology and Accident Research Laboratory performed toxicological testing of specimens from the instructor and the student. According to the postmortem toxicology report, results for the student were negative for carbon monoxide, cyanide, ethanol and screened drugs. The toxicology report for the instructor was negative for carbon monoxide, cyanide, and screened drugs. The instructor's toxicological test results were positive for the following:

10 mg/dL, mg/hg ETHANOL detected in Blood

33 mg/dL, mg/hg ACETALDEHYDE in Blood.

The report indicated that the ethanol found in this case was from postmortem ethanol formation and not from the ingestion of ethanol.

TESTS AND RESEARCH

The airplane was recovered from the accident scene and was reexamined on December 8, 2003. The upper right leg of the cockpit's flight control Y was observed bent and broken. The vertical portion of the control Y exhibited a bending break consistent with an over-travel in the direction it was observed bent.

The NTSB Materials Laboratory examined fore and aft portions of the left rudder control cable. The Supervisory Metallurgist concluded that all features on the cable pieces were typical of an overstress separation. There was no evidence of corrosion or wear.

The elevator control tube was severed at the follower assembly, and a 3-inch section that attached the aft elevator control tube to the follower was not recovered. The airplane representative examined the sections of elevator control tube involved in the accident and the elevator control assembly of a sister ship. By design, the attachments of both the fore and aft elevator tubes are fixed at both ends. The tube moves along a follower assembly. With the elevator in the full aft position, the aft control tube attachment rests against the follower assembly. The representative opined that the aft elevator tube was sheared just aft of the attachment as ground impact occurred.

According to FAA personnel, air traffic control did not assign the accident airplane a discrete transponder squawk code. A review of recorded airport surveillance radar, from the High Desert Terminal Radar Approach Control facility located at the Edwards Air Force Base, was undertaken for the flight tracks of all aircraft departing runway 26 and disappearing over the crash site. Only one radar track matched the accident airplane's projected flight track. Safety Board investigators reviewed the flight track for this airplane during a real-time replay event at the Edwards Air Force Base facility in order to determine the flight path.

A Safety Board Research and Engineering specialist also reviewed the radar hits and the airplane's projected flight path. The entry speed into the final maneuver was calculated to be 92 mph, and the descent rate increased to more than 5,000 feet per minute. The flight path indicated by the final radar retur

NTSB Probable Cause

The flying pilot's failure to obtain/maintain control of the airplane during practice stalls, which resulted in the inadvertent entry into a spin.