History of Flight
On July 25, 2020, about 1338 mountain daylight time, a Piper PA-32-300R, registration N7677C, was substantially damaged when it was involved in an accident near South Valley Regional Airport (U42), West Jordan, Utah. The pilot, two passengers, and one person on the ground sustained fatal injuries; two passengers sustained serious injuries; and one passenger sustained minor injuries. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight.
According to an employee of the fixed-base operator at the airport, he received a telephone call from a woman who asked to have the airplane “filled up.” The employee also stated that, about 1310 to 1320, the pilot and passengers arrived at the airport and started to load their bags. Another employee added 66.8 gallons of 100 low-lead aviation gasoline to the airplane.
A security camera captured the pilot performing a preflight inspection. After boarding, the engine was started, and the airplane taxied toward runway 16. While on the taxiway, the windsock indicated wind from the north. About 3 minutes later, the airplane was observed during the takeoff roll. A second security camera showed the airplane lifted off at 1336:54 and became airborne abeam taxiway A2, about 3,700 ft from the start of runway 16. The airplane departed straight out to the south on a magnetic heading of about 170° and made a series of slight climbs and descents. About 1 minute 15 seconds after takeoff (1338:09), the airplane reappeared descending at a steep angle into a neighborhood, followed by a large plume of black smoke.
Downloaded GPS data indicated the airplane departed U42 about 1336 and traveled southeast on a magnetic heading of 165° for about 1.3 miles, then turned left to about 136° for 0.2 miles. It climbed to an altitude of 4,720 ft msl (about 120 ft agl) and accelerated to a groundspeed of about 82 knots. The last GPS point, at 1338:24, recorded the airplane near the accident site at an altitude of 4,603 ft msl (about 10 ft agl) and a groundspeed of about 1 knot.
Multiple witnesses reported the engine sounded loud, and others observed the airplane at a very low altitude before it descended nose down. One witness stated the airplane “started to bank to the east” and “looked like it fell from the sky.” Multiple witnesses also reported a house in the neighborhood was on fire.
During a postaccident interview, the pilot’s wife (a passenger) stated that he planned an instrument flight rules flight over the Grand Canyon and possibly Lake Powell. The pilot computed weight and balance and showed her the paperwork. She indicated he was aware of the high temperature and high altitude and assured her “it’s all good.” Another surviving passenger stated that everything was “fine” after takeoff but that shortly afterward the airplane “dropped down” and “the cabin was shaking.” She heard an “on and off buzzing” sound after liftoff that lasted until impact. She also stated the pilot asked about everyone’s weight and the bags were weighed.
Personnel Information
Flight instructors who provided instrument flight training stated the pilot handled the airplane easily. One instructor stated he reviewed density altitude and normally aspirated engines with the pilot due to multiple cross-country flights to Utah; the pilot “didn’t understand why” the instructor continued to bring up pressure altitude and density altitude. The pilot received a high-performance and complex endorsement on December 31, 2019.
Aircraft Information
The airplane was powered by a 300-horsepower Lycoming O-540-K1G5D, a normally aspirated engine, with a Hartzell constant-speed propeller. The last annual inspection was on October 18, 2019, at a total time of 451 hours. The engine was last overhauled on December 28, 2012, at a total time of 3,060 hours.
Data from an engine data monitor (EDM) revealed consistent engine operation for the first 10 minutes. About 1337, exhaust gas temperature (EGT) of all cylinders increased rapidly from about 1,280°F to a maximum of about 1,600°F, and fuel flow decreased from about 28 to 19 gallons per hour. About 5 seconds later, EGTs decreased to about 1,500°F and fuel flow increased to about 22 gallons per hour, consistent with mixture control adjustments. The EDM stopped recording about 1338.
The calculated takeoff weight was about 3,531 pounds. Basic empty weight was 2,257 pounds, fuel 564 pounds, pilot and passengers estimated 690 pounds, baggage 20 pounds. The center of gravity was 92.84 inches aft of datum (maximum aft CG 95 inches, maximum gross weight 3,600 pounds). Performance charts for the weight and environmental conditions predicted a gear-up rate of climb of about 500 ft per minute. Stall speed was calculated at about 65 knots calibrated airspeed with flaps up and 61 knots for flaps 25°.
Meteorological Information
At 1355, the automated weather at U42 reported wind 320° at 7 knots, visibility 10 statute miles, clear skies, temperature 32°C, dew point 7°C, barometric pressure 30.06 inches of mercury. Density altitude was calculated to be 7,292 ft msl.
Airport Information
South Valley Regional Airport (U42) is located in West Jordan, Utah.
Wreckage and Impact Information
The airplane first impacted a tree and the edge of a roof on a house. The tree exhibited multiple 45° cuts to branches, consistent with propeller contact. The airplane then struck a second house and its detached garage before coming to rest in the backyard of a third house, about 1.5 miles southeast of U42. The debris path extended about 95 ft on a magnetic heading of about 130°. The airplane came to rest on its left side on a heading of about 170°.
All major components were within the main wreckage. Both wings separated at their roots and came to rest about 20 ft behind the main wreckage. A postimpact fire consumed the left wing and damaged most of the right wing and cabin. The right flap was observed in the 10°/first-notch position; the flap torque tube’s right control arm was at the 1:00 position, consistent with that setting.
Flight control continuity was established from the aileron control cable to breaks at the wing roots. Cable breaks exhibited a splayed, broomstraw appearance. Continuity was also established at the wing roots to the aileron bell cranks and to the right aileron. Elevator and rudder control continuity was established. The nose and right main landing gear were retracted; the left main was consumed by fire.
Postaccident engine examination revealed 6 of 12 spark plugs (4 top, 2 bottom) had severely worn electrodes. The No. 3 cylinder had severely worn top and bottom electrodes. According to the engine manufacturer, the worn electrodes were still capable of producing a spark. No mechanical malfunctions or anomalies were observed that would have precluded normal engine operation.
Additional Information
Federal Aviation Administration (FAA) Pamphlet FAA-P-8740-2, *Density Altitude*, states that high density altitude reduces air density and aircraft performance, and outlines hazards including reduced takeoff performance and the need to lean normally aspirated engines for maximum power at density altitudes above 5,000 feet. The FAA’s *Airplane Flying Handbook* notes that under high-density altitude conditions, the airplane may lift off but be unable to climb out of ground effect. The *Pilot's Handbook of Aeronautical Knowledge* states that reduced drag in ground effect may allow takeoff below recommended speed, but rising out of ground effect with a speed deficiency may result in marginal climb performance; in extreme conditions, the aircraft may become airborne but be incapable of sustaining flight out of ground effect.