CEN20FA070

The pilot’s failure to follow the instrument landing system (ILS) course guidance during the instrument approach.

The pilot was conducting an instrument landing system (ILS) approach in instrument meteorological conditions at the conclusion of a cross-country flight. The airplane had been cleared to land, but the tower controller canceled the landing clearance because the airplane appeared not to be established on the localizer as it approached the locator outer marker. The approach controller asked the pilot if he was having an issue with the airplane’s navigation indicator, and the pilot replied, “yup.” Rather than accept the controller’s suggestion to use approach surveillance radar (ASR) approach instead of the ILS approach, the pilot chose to fly the ILS approach again. The pilot was vectored again for the ILS approach, and the controller issued an approach clearance after he confirmed that the pilot was receiving localizer indications on the airplane’s navigation equipment. The airplane joined the localizer and proceeded toward the runway while descending. The pilot was instructed to contact the tower controller; shortly afterward, the airplane entered a left descending turn away from the localizer centerline. At that time, the airplane was about 3 nautical miles from the locator outer marker. The pilot then told the tower controller, “we’ve got a prob.” The tower controller told the pilot to climb and maintain 3,000 ft msl and to turn left to a heading of 180°. The pilot did not respond. During the final 5 seconds of recorded track data, the airplane’s descent rate increased rapidly from 1,500 to about 5,450 ft per minute. The airplane impacted terrain about 1 nm left of the localizer centerline in a left-wing-down and slightly nose down attitude at a groundspeed of about 90 knots. A postimpact fire ensued. Although the pilot was instrument rated, his recent instrument flight experience could not be determined with the available evidence for this investigation. Most of the fuselage, cockpit, and instrument panel was destroyed during the postimpact fire, but examination of the remaining wreckage revealed no anomalies. Acoustic analysis of audio sampled from doorbell security videos was consistent with the airplane's propellers rotating at a speed of 2,500 rpm before a sudden reduction in propeller speed to about 1,200 rpm about 2 seconds before impact. The airplane’s flightpath was consistent with the airplane’s avionics receiving a valid localizer signal during both instrument approaches. However, about 5 months before the accident, the pilot told the airplane’s current maintainer that the horizontal situation indicator (HSI) displayed erroneous heading indications. The maintainer reported that a replacement HSI was purchased and shipped directly to the pilot to be installed in the airplane; however, the available evidence for the investigation did not show whether the malfunctioning HSI was replaced before the flight. The HSI installed in the airplane at the time of the accident sustained significant thermal and fire damage, which prevented testing. During both ILS approaches, the pilot was cleared to maintain 3,000 ft mean sea level (msl) until the airplane was established on the localizer. During the second ILS approach, the airplane descended immediately, even though the airplane was below the lower limit of the glideslope. Although a descent to the glideslope intercept altitude (2,100 ft msl) would have been acceptable after joining the localizer, such a descent was not consistent with how the pilot flew the previous ILS approach, during which he maintained the assigned altitude of 3,000 ft msl until the airplane intercepted the glideslope. If the HSI provided erroneous heading information during the flight, it could have increased the pilot’s workload during the instrument approach and contributed to a breakdown in his instrument scan and his ability to recognize the airplane’s deviation left of course and descent below the glideslope; however, it is unknown if the pilot had replaced the HSI.

A review of available logbook documentation revealed that the pilot's last recorded flight was for a 2017 flight review. The available evidence for this investigation did not indicate whether the pilot had a more current logbook. The pilot was instrument rated, but his recent instrument flight experience could not be determined with the available evidence. From August 21 to 23, 2019, the pilot received initial training in the Piper PA60601P airplane from Advanced Flight Training International, Sarasota, Florida. The flight instructor who provided the training stated that the pilot had received a certificate of completion that was limited to visual flight rules (VFR) operations because the airplane had a malfunctioning horizontal situation indicator (HSI) during training, which prevented an evaluation of the pilot's ability to fly solely by reference to instruments. The flight instructor stated the pilot had demonstrated, "very good piloting skills operating the aircraft in a safe manner and keeping it within its limitations." The airplane was equipped for operations in instrument meteorological conditions and icing conditions. The airplane’s total fuel capacity of 173.5 gallons (165.5 gallons usable) was distributed between two wing fuel tanks and a fuselage tank. According to fueling documentation, the airplane's fuel system was topped-off before the accident flight. Shortly after purchasing the airplane in August 2019, the pilot had an issue with the airplane’s HSI not synchronizing with the remote compass. According to the airplane’s current maintainer, an overhauled HSI was purchased and shipped directly to the pilot to be installed in the airplane. A review of available maintenance documentation and discussions with several maintenance facilities were unable to establish if the malfunctioning HSI had been replaced before the flight. The HSI installed in the airplane at the time of the accident sustained significant thermal and fire damage which prevented testing. The airplane impacted a harvested cornfield about 6.3 nm southeast of the runway 31 threshold and about 1 nm left of the localizer centerline. A 200 ft long debris path, oriented on a 248° magnetic heading, preceded the location of the main wreckage. The airplane's left wingtip impacted the ground first, followed by the left and right propellers, respectively. The nose landing gear wheel was found separated from the fork assembly about 40 ft from the initial point of impact. The outboard 2.5 ft of the left aileron was found separated from the left wing along the wreckage debris path. The main wreckage came to rest at the western edge of the cornfield amongst several trees and a wire fence, and consisted of the entire fuselage, both wings, and the empennage. The fuselage cabin and cockpit exhibited extensive damage from the postaccident fire. Both wing spars were fractured at their wing roots and each wing remained partially attached to the fuselage by engine control cables. Flight control continuity could not be verified because the control push/pull tubes for the ailerons, elevators, and rudder exhibited extensive impact and fire damage. Both ailerons and flaps exhibited impact and fire damage. The hydraulic flap actuators were found extended about 1.5" consistent with about 20° of flap extension. The flap control handle was found in an intermediate position. Both elevators remained attached to the horizontal stabilizer and exhibited fire damage. The rudder remained attached to the vertical stabilizer; however, most of the rudder was destroyed by fire. The landing gear selector handle was not located during the investigation, but the landing gear was found extended at the accident site. The throttle quadrant was destroyed by impact and fire damage. The instrument panel sustained significant thermal damage during the postaccident fire. The airspeed indicator and altimeter were destroyed by fire. The attitude indicator and HSI were extensively damaged by fire and could not be tested. The internal gyros of the attitude indicator and HSI did not exhibit any evidence of rotational scoring. The turn indictor gyro was found separated from its instrument case that was not located during the investigation. The turn indicator gyro did not exhibit any evidence of rotational scoring. The backup course deviation indicator was destroyed by fire. The electronic engine trend monitor was destroyed by fire. The engine tachometer indicated 1,200 rpm for both engines. The manifold pressure gauge indicated 28 and 30 inches of mercury for the left and right engines, respectively. Both engines remained attached to their respective engine mounts and nacelles. Internal engine and valve train continuity were confirmed for each engine. Compression and suction were noted on all cylinders in conjunction with crankshaft rotation. Both magnetos on each engine were damaged by fire and could not be tested. The spark plugs exhibited features consistent with normal engine operation. Borescope examination of each cylinder did not reveal any anomalies with the cylinders, pistons, valves, or valve seats. Both oil pumps discharged oil when their respective engine crankshaft was rotated. The pressure pump installed on each engine could not be rotated because of fire damage to their respective drive gears; however, a partial disassembly of both pumps revealed no evidence of internal failure that would have precluded normal function during flight. The turbocharger system components remained secured at their respective mounts. The turbocharger compressors and turbine impellers remained intact and undamaged. The turbine impellers rotated freely by hand. The exhaust bypass valves remained secured at each turbocharger exhaust pipe and their butterfly valves remained intact and undamaged. The postaccident engine examinations did not reveal any anomalies that would have precluded normal operation during the flight. The left propeller remained attached to the engine propeller shaft flange. The spinner dome was dented with one counterweight mark on the internal surface in the normal blade angle range of operation. Propeller blade no. 1 was bent aft, bent opposite rotation and twisted towards low pitch. Propeller blade no. 2 was bent slightly aft with no remarkable twisting. Propeller blade no. 3 was bent aft, opposite rotation and twisted towards low pitch. All three propeller blades exhibited chordwise/rotational scoring isolated to the leading edges on both the camber and face side. The low pitch stop had an impact mark consistent with the propeller operating on or near the low pitch stop angle. The right propeller remained attached to the engine propeller shaft flange. All three propeller blades appeared to be in the normal blade angle range. The spinner dome was dented with counterweight impressions that were consistent with normal blade angle range of operation. All three propeller blades were bent aft, opposite rotation in varying degrees and twisted towards low pitch. All three propeller blades exhibited chordwise/rotational scoring isolated to the leading edges on both the camber and face side. The low pitch stop had an impact mark consistent with the propeller operating on or near the low pitch stop angle. On January 28, 2020, about 1503 central standard time, a Piper PA-60-601P airplane, N6071R, was destroyed when it was involved in an accident near Springfield Abraham Lincoln Capital Airport (SPI), Springfield, Illinois. The pilot and two passengers, and a dog were fatally injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. About 1301, the flight departed from Huntsville International Airport (HSV), Huntsville, Alabama, on an instrument flight rules (IFR) flight plan to SPI. According to automatic dependent surveillance-broadcast (ADS-B) data, the flight departed runway 18L at HSV and turned north-northwest toward SPI. The airplane subs