On February 5, 2016, a NORTH AMERICAN F51 D (registration N551JP) was involved in an aviation accident near Maricopa, AZ. 2 people were killed. Investigators recorded the probable cause as: The pilot’s failure to maintain airplane control while performing an acrobatic maneuver and his subsequent failure to recover from an inadvertent spin due to insufficient altitude. This summary draws on records from NTSB; 12 related events involving the same aircraft type or operator are linked below.
On Feb 5, 2016, an F-51D crashed near Maricopa, Arizona, killing the pilot and passenger. Witnesses reported acrobatic maneuvers. No pre-impact mechanical anomalies were found.
Accident Overview and Immediate Circumstances On February 5, 2016, at approximately 1157 mountain standard time, a North American F-51D, registration N551JP, struck terrain roughly 6 miles southwest of Maricopa, Arizona. The aircraft sustained substantial damage, and both the commercial pilot and the pilot-rated passenger were killed. The flight, a local personal operation under 14 Code of Federal Regulations Part 91, had departed Stellar Airpark in Chandler, Arizona, earlier that morning. Visual meteorological conditions prevailed, and no flight plan was filed. ## Witness Accounts and Flight Path Witnesses located between 0.5 and 1 mile from the crash site reported observing the aircraft performing acrobatic-type maneuvers, with one describing a “regular loop.” The witness noted that during the latter half of the maneuver, the aircraft did not pull up and estimated its altitude at approximately 2,500 feet above ground level at the apex. Other witnesses observed the aircraft descending in a nose-down spiral until impact. All witnesses who commented on the engine reported hearing it running throughout the descent, with some describing a transition from full power to a lower power setting. ## Personnel and Aircraft Details The pilot held a commercial pilot certificate with multiple ratings and a flight instructor certificate. His third-class airman medical certificate, issued on March 10, 2015, carried a limitation that it would not be valid for any class after March 31, 2016. At the time of his most recent medical application, he reported 6,700 total flight hours and 105 hours in the preceding six months. The aircraft, a dual-seat, low-wing, retractable-gear, tail-wheel airplane, was manufactured in 1944 and served as an American fighter during World War II. Maintenance records indicated the last annual inspection and a 100-hour conditional engine check were completed on August 10, 2015, at an airframe hour meter time of 1,882 hours. The engine had 2.4 hours since overhaul at that time. The current weight and balance form could not be located, and the investigation could not determine the aircraft’s weight and balance condition at the time of the accident. ## Meteorological and Airport Information Automated weather data from Casa Grande Municipal Airport, located approximately 21 miles east of the accident site, recorded conditions at 1155 as wind from 010° at 6 knots, visibility 10 statute miles, clear sky, temperature 15°C, dew point -7°C, and an altimeter setting of 30.36 inches of mercury. ## Wreckage and Impact Examination The NTSB investigator-in-charge determined the aircraft impacted terrain at an elevation of approximately 1,274 feet. All major components were contained within the main wreckage site, with debris consisting primarily of broken canopy pieces and small metal fragments scattered about 150 feet in front. The first point of contact was a large area of disturbed dirt, measuring about 4 feet by 3 feet and 6 inches deep, located 5 feet aft of the wreckage. The aircraft was partially buried, with two of the four propeller blades completely buried and the remaining two with about one-third of their blades in the ground. The fuselage came to rest upright on a heading of about 180° magnetic, perpendicular to the edge of a road. A post-impact fire scorched an area of light vegetation measuring about 25 feet by 150 feet across the road. Most of the fuselage structure and wings were consumed by fire. The wings sustained thermal damage, and leading-edge compression damage was observed on both wings. The empennage was crushed and sustained thermal damage. Flight control continuity was established from the individual flight controls to the center portion of the cabin. ## Additional Information and Aircraft Manual The F-51D Aircraft Flight Manual states that no intentional power-on spins or snap rolls are permitted, as most attempts end in a power spin. It further states that no intentional power-off spins are permitted below 12,000 feet. The manual warns that power-on spins are extremely dangerous in this aircraft, noting that the nose remains 10 to 20 degrees above the horizon and recovery control has no effect until the throttle is completely retarded. Recovery from a power-on spin may involve 5 or 6 turns and a loss of 9,000 to 10,000 feet of altitude. Subtracting the accident site elevation from the aircraft’s highest recorded altitude of 7,700 feet MSL would allow for approximately 6,426 feet of altitude for a spin recovery. The manual lists estimated stall speeds at a gross weight of 9,000 lbs, with gear and flaps up, as 101 mph level, 109 mph at 30° of bank, and 121 mph at 45° of bank. At 10,000 lbs, the stall speeds are 106 mph level, 115 mph at 30° of bank, and 128 mph at 45° of bank. ## Medical and Pathological Information The Pima County Office of Medical Examiner determined the pilot’s cause of death was multiple blunt force injuries. Toxicological testing by the FAA’s Bioaeronautical Sciences Research Laboratory was negative for carbon monoxide, cyanide, volatiles, and tested-for drugs. Ethanol was detected in the muscle and liver. The pilot’s FAA medical records included multiple cardiology evaluations due to a history of arrhythmia and stroke. He suffered a cardioembolic stroke in March 2012 due to a blood clot resulting from atrial fibrillation, which was successfully ablated in June 2012. At his last FAA medical exam, he reported using rivaroxaban (Xarelto), a blood thinner. The most recent cardiology evaluation in his FAA records, dated February 2015, found no evidence of recurrent atrial fibrillation or significant cardiovascular abnormalities. Neurological evaluations, most recently from August 2013, found no significant motor or cognitive impairment. The pilot’s cardiology records from his treating cardiologist for January 2014 to February 2016 showed his most recent visit was on February 5, 2016, the day of the accident. This visit was a follow-up on his annual Holter monitor study. The physician documented that the pilot had done very well in the past year with no palpitations indicating atrial fibrillation. The examination documented a normal cardiovascular examination and a normal EKG, and the 24-hour monitor showed no evidence of atrial fibrillation. The cardiologist stated that from a cardiovascular standpoint, the pilot was fit for a third-class medical certificate. ## Tests and Research On April 11 and 12, 2016, the airframe and engine were examined at the facilities of Air Transport in Phoenix, Arizona. A majority of the fuselage was extremely fragmented. The airspeed indicator displayed about 530 miles per hour. The left and right wing leading edges exhibited compression aft to the wing spar throughout their entire span. The forward and aft control stick assemblies were located. The forward control stick remained attached but was separated into multiple sections. The aft control stick was bent forward near the base and aft near the upper portion. Both control sticks exhibited ductile overload fractures, with no corrosion or cracks present. The engine was mostly intact, with visual continuity established for the crankshaft, connecting rods, and pistons. One of the four propeller blades had separated, exhibiting “S” bending signatures, leading edge gouges, and chordwise scratches. Two attached blades were slightly bent with leading edge damage and chordwise striations, while the other attached blade exhibited slight bending and chordwise striations. No pre-impact anomalies were found that would have precluded normal operation. ## Performance Study A performance study conducted by the NTSB Office of Research and Engineering used airport surveillance radar to determine the aircraft’s ground track, altitude, and speed. Radar data began at 1154:59 when the aircraft was northwest of Maricopa, Arizona. The aircraft climbed from an initial altitude of 5,400 feet to 6,100 feet MSL and, at 1156:45, descended to 5,700 feet MSL. Airspeeds increased from 180 knots to 250 knots during this portion of the flight, consistent with maneuvering to enter a climbing acrobatic-type maneuver. The study determined that the aircraft’s maneuvering and speed during this period were well within the flight envelope. A secondary set of radar data started after 1156:45, when the aircraft was about 5 miles southwest of Maricopa. Ten more radar returns were recorded, but only one recorded an altitude. The fifth data point, at 1156:59, indicated 7,700 feet MSL. Several data points were closely grouped with no associated altitude information, which acrobatic maneuvering could account for due to the transponder’s position relative to the radar antenna. By 1156:59, the airspeed had slowed to about 100 knots. Climbing to 7,700 feet would have required a significant nose-up pitch attitude and a rate of climb of over 8,000 feet per minute from the previously known radar point at 1156:45. The last secondary radar return was located about 2,600 feet from the aircraft wreckage location.