History of Flight
On March 3, 2023, about 1600 eastern standard time, a Bombardier BD-100-1A10 (Challenger 300) airplane, registration N300ER, was involved in an accident near Windsor Locks, Connecticut. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. One passenger was fatally injured; the two airline transport pilots and two other passengers were not injured. The airplane incurred minor damage.
The flight crew had completed a flight from Leesburg Executive Airport (JYO), Virginia, to Dillant/Hopkins Airport (EEN), New Hampshire, with the accident passengers the day before. The accident flight was the return to JYO.
The second-in-command (SIC) conducted an exterior preflight inspection but inadvertently left the non-streamer pitot cover on the right pitot probe after assisting a lineman. The pilot-in-command (PIC) did not observe the cover. During the takeoff roll on runway 2 at EEN, the right primary flight display airspeed indicator failed to show acceleration above 40 knots, while the left showed normal acceleration. The crew rejected the takeoff. The left engine was shut down on the taxiway, and the SIC removed the pitot cover.
After the rejected takeoff, a Crew Alerting System (CAS) cyan advisory "RUDDER LIMITER FAULT" message appeared. The PIC attempted avionics stall tests to clear the message, which were unsuccessful. The crew discussed the message and agreed to continue the flight despite the advisory, which was listed as a "NO GO" item in the Quick Reference Handbook (QRH). The PIC did not refer to the QRH Go/No-Go guide.
The crew taxied for a second takeoff. During the takeoff roll, no V-speed bugs were displayed, but the SIC announced V1 at about 116 knots based on memory. The airplane became airborne at 1535:27.
During the climb, multiple CAS caution messages appeared: "MACH TRIM FAIL," "AP STAB TRIM FAIL" (Autopilot Stabilizer Trim Failure), and "AP HOLDING NOSE DOWN." The autopilot was engaged and disengaged multiple times. The SIC located the PRI STAB TRIM FAIL checklist on an electronic flight bag and the crew agreed to execute it. The first action was to move the stabilizer trim switch from "PRI" to "OFF." As soon as the switch was moved, the autopilot disconnected, and the elevator rapidly moved to neutral, causing rapid pitch oscillations. The PIC input nose-down force, and the airplane pitched up again, activating the stall protection system. The inertial g switch triggered, stopping the flight data recorder.
Moments after the upset, a passenger alerted the crew that another passenger was seriously injured. The crew declared a medical emergency and diverted to Bradley International Airport (BDL) in Windsor Locks. The PIC manually flew the airplane and landed about 17 minutes after the upset. Paramedics transported the injured passenger to a hospital, where she later died.
Investigation Findings
Data from the flight data recorder (FDR) and horizontal stabilizer trim electronic control unit (HSTECU) showed that during the rejected takeoff, an airspeed mismatch between Air Data Computers 1 and 2 exceeded 20 knots for more than 5 seconds. This caused the HSTECU to latch an "ADC1/ADC2 Miscompare" fault, which resulted in the "RUDDER LIMITER FAULT" advisory. Additionally, "Confirmed Mach Valid" latched to FALSE, leading to the "MACH TRIM FAIL" caution, loss of Mach trim, inhibition of autopilot trim function, and reduced manual trim rate. When the autopilot was engaged, the inhibited trim function caused the "AP STAB TRIM FAIL" and "AP HOLDING NOSE DOWN" messages. No evidence of a system malfunction was found other than the issues resulting from the rejected takeoff. The HSTECU latched faults could have been cleared by power cycling the unit.
Passenger Seating and Injuries
The fatally injured passenger was seated in position No. 3. During the climb, the passenger may have left the seat to use the lavatory. The seatbelt sign was on for the entire flight according to the PIC, but no passenger announcements were made before the upset. After the in-flight upset, the No. 1 passenger found the fatally injured passenger lying near the lavatory in the aisle.
Aircraft and Operator Information
The airplane, a Bombardier Challenger 300, was powered by two Honeywell HTF7000 engines. It was managed by Executive Flight Services (EFS) and owned by Conexon LLC. The flight was a non-revenue Part 91 operation. The PIC had 5,061 total flight hours, with 88 hours in the accident make and model. The SIC had 8,025 total hours, with 78 hours in type. Both pilots completed initial training in October 2022.
The EFS General Operations Manual required a final walk-around before each flight, which was not completed. The QRH listed the "RUDDER LIMITER FAULT" as a "NO GO" item, but the crew did not consult this guide.
Simulator testing at CAE in Dallas determined that the simulator could not reproduce the exact indications experienced by the accident crew without abnormal settings.