N6945Q

HISTORY OF FLIGHTOn December 10, 2023, about 1019 central standard time, a Beech A23-24 airplane, N6945Q, was destroyed when it was involved in an accident near Oklahoma City, Oklahoma. The pilot and his passenger were fatally injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight.

According to recordings of air traffic control (ATC) communications at Wiley Post Airport (PWA), Oklahoma City, Oklahoma, at 1008:16, the pilot established contact with the ground controller and requested a visual flight rules (VFR) departure to the north. At 1008:42, the ground controller issued a taxi clearance to runway 35R via taxiway C1, cleared the airplane to cross runway 31, and asked the pilot if he wanted VFR flight following. At 1008:48, the pilot told the ground controller that he did not need VFR flight following and then correctly read back the taxi clearance.

At 1015:37, the pilot contacted the tower controller and stated that he was holding short of runway 35R on taxiway A1 and was ready to depart to the north under VFR. At 1015:44, the tower controller cleared the pilot for takeoff on runway 35R.

A review of ADS-B track data revealed that the airplane’s liftoff occurred before midfield and the airplane was climbing though 350 ft above ground level (agl) as it flew over the end of runway 35R.

At 1016:57, a security camera located on a hangar near the east end of taxiway A5 captured the airplane in a climb from runway 35R. As the airplane continued the climb to the north there was possible evidence of intermittent smoke trailing behind the airplane.

According to ADS-B track data, after takeoff the airplane continued the climb while on a north ground track, as shown in figure 1. At 1018:21, the airplane entered a left turn and about 3 seconds later the pilot told the tower controller, “… we’re a return for landing.”

At 1018:33, the tower controller cleared the pilot to enter a left downwind for runway 35R. At 1018:38, the pilot transmitted, “okay, we are losing power [unintelligible] tower I’m gonna land on [unintelligible].” During the pilot’s transmission, the engine was heard in the background running roughly.

Figure 1. Plot of airplane flight track data.

At 1018:43, the airplane was about halfway through a 180° turn toward the airport when it began a descent from the flight’s maximum altitude of about 2,165 ft mean sea level (msl), as shown in figures 2 and 3. At that time, the airplane was about 1.7 nautical mile (nm) from the runway 17R threshold and 882 ft above the runway threshold height. According to the Beech A23-24 Pilot Operating Handbook, the airplane’s maximum glide was achieved at the best glide airspeed of 82 knots with the flaps up and the propeller control full aft. If properly configured and flown, the airplane’s glide distance in a zero-wind condition was about 1.7 nm per 1,000 ft of altitude above terrain.

At 1018:51, the pilot stated “… I’m declaring an emergency.” The tower controller subsequently cleared the pilot to land on the runway of his choice. At 1019:29, the tower controller stated that the surface wind was from 320° at 5 knots.

The ADS-B flight track data showed the airplane continued to descend toward the airport and runway 17R. At 1019:50, the final ADS-B return was recorded about 0.4 nm north of the runway 17R threshold at an altitude of about 1,445 ft msl. At that time, the airplane was about 162 ft agl, 68 knots calibrated airspeed, and descending about 1,355 feet per minute (fpm).

The same security camera that captured the airplane’s takeoff from runway 35R also captured the airplane as it descended toward the airport. At 1019:13, the video footage showed the airplane descending with light colored smoke trailing the airplane. At 1020:04, dark smoke began rising from the accident site location.

Two witnesses reported smoke trailing from the airplane and that the engine was running roughly before the accident. One witness noted that the trailing smoke was a gray/white color. A third witness stated that the engine was sputtering as the airplane flew over his position and then it made a 180° turn toward the airport.

Figure 2. Plots of airplane altitude, ground speed, true airspeed, calibrated airspeed, and

vertical speed.

Figure 3. Plots of airplane heading, roll angle, and flight path angle. PERSONNEL INFORMATIONThe pilot’s flight logbook was not located during the investigation.

According to FAA documentation, just over two months before the accident, on October 7, 2023, the pilot passed his private pilot check ride that was administered by an FAA Designated Examiner. On his application for the pilot certificate, the pilot reported a total flight time of 80.2 hours, of which 10 hours were flown as pilot-in-command.

Based on recorded ADS-B flight track data, the airplane was flown at least 17.5 hours after the pilot purchased the airplane on June 30, 2023. Of that total, about 9.5 hours were flown after the pilot received his private pilot certificate on October 7, 2023. AIRCRAFT INFORMATIONAccording to available maintenance documentation, the last major overhaul of the Lycoming IO-360-A2B engine, s/n L-3904-51A, was completed on June 6, 2005, at 398.92 hours (all logbook entries were based on tachometer time). At the time of the overhaul, the engine had accumulated 924.9 hours since new.

On December 24, 2008, at 637.78 hours, all four cylinders were removed and overhauled due to low cylinder compression and excessive oil consumption. Postaccident calculations based on previous tachometer readings indicated that the engine had 238.86 hours since major overhaul (SMOH) when the cylinders were overhauled.

On January 12, 2021, the recording tachometer was rebuilt, reset to 0.0 hours, and then reinstalled in the airplane. Postaccident calculations based on previous tachometer readings indicated that the airframe total time (AFTT) and engine SMOH were 1,397.91 hours and 474.48 hours, respectively.

On April 15, 2023, at 209.3 hours, 683.78 hours SMOH, the engine oil and oil filter were replaced, No. 1 cylinder was serviced due to low compression. The No. 1 cylinder bore was honed, and new gaskets and hold-down nuts were installed. The airplane was returned to service following an engine ground run and subsequent test flight that did not reveal any oil leaks or anomalies. The associated engine log entry indicated that the engine was inspected in accordance with an annual inspection and determined to be in an airworthy condition.

Also completed on April 15, 2023, was the airplane’s last annual inspection. Postaccident calculations based on previous tachometer readings indicated that the AFTT and engine SMOH were 1,607.21 hours and 683.78 hours, respectively.

According to FAA registration records, the pilot purchased the airplane on June 30, 2023. A prepurchase inspection report, dated June 22, 2023, at 210.1 hours, completed by an aviation mechanic from Twin Aviation Repair, LLC, Douglas, Georgia, indicated that the AFTT and engine SMOH were 1,585.31 hours and 684.5 hours, respectively. However, based on postaccident calculations based on previous tachometer readings indicated the AFTT was 1,608.01 hours.

On November 3, 2023, at 225.0 hours, 699.48 hours SMOH, the engine oil and oil filter were replaced, and an oil sample was submitted to a laboratory for analysis. The airplane was returned to service following an engine test run that did not reveal any oil leaks or anomalies.

The oil analysis report, dated December 5, 2023, indicated elevated levels of aluminum, chromium, and iron. The laboratory commented that there was “a lot of metal in this sample” and that internal corrosion could be an issue if the airplane had been sitting. The laboratory suggested a borescope inspection, compression test, monitor oil temperature, and check the oil filter for evidence of metal. Additionally, the laboratory report stated that excessive oil consumption could also be an indication of engine issues.

On December 5, 2023, the aviation mechanic who submitted the oil sample sent the pilot/owner an email to discuss the results of the oil sample that was collected on November 3, 2023, during the last oil change. The mechanic wrote that the oil sample had high level of chrome and that it might be from internal corrosion and possibly attributable to cylinder wear. The mechanic also acknowledged that the cylinder compression values during the prepurchase inspection were nominal and that there had been recent cylinder work completed. As such, the mechanic recommended recurring 25-hours oil sample analyses, and 50-hour compression checks with borescope inspections until the chrome levels trended down to normal levels. The pilot/owner agreed and told the mechanic that he would advise him when the airplane had flown 25 hours since the last oil change.

On December 1, 2023, at 233.9 hours, an E-Z Heat oil sump heater was installed on the engine. Postaccident calculations based on previous tachometer readings indicated that the AFTT and engine SMOH were 1,631.81 hours and 708.38 hours, respectively. The aviation mechanics who installed oil sump heater stated that the back screws of the lower cowling were removed to gain access underneath the engine to install the oil-sump heater, but none of the engine oil system components were loosened or removed to gain access to the engine sump.

The airplane’s recording tachometer was destroyed by the postimpact fire, which prevented calculation of the airplane’s airframe and engine times at the time of the accident. AIRPORT INFORMATIONAccording to available maintenance documentation, the last major overhaul of the Lycoming IO-360-A2B engine, s/n L-3904-51A, was completed on June 6, 2005, at 398.92 hours (all logbook entries were based on tachometer time). At the time of the overhaul, the engine had accumulated 924.9 hours since new.

On December 24, 2008, at 637.78 hours, all four cylinde...