The fatal crash of a Bombardier Challenger 601-3A on May 5, 2019, was the result of “a loss of control due to a rapid climb and inversion caused by severe atmospheric instability, inducing both engines to shut down,” according to the final report from Mexico’s DGAC. A contributing factor was the “inability of the aircraft’s [weather] radar to provide information for an undetermined reason.” The two crew members and 11 passengers were killed in the accident.
The aircraft, N601VH, took off at about 3 p.m. from Las Vegas on a Part 91 IFR flight to Monterrey, Mexico, according to the report. At about 5:30 p.m., the aircraft began encountering turbulence and ATC granted a request to climb from FL390 to FL410. Not long after, the aircraft disappeared from ATC radar and communication were lost.
According to cockpit voice recorder data, the copilot asked, “Nothing on the radar?”, to which the captain responded, “Nada.” But flight data recorder information indicated that the aircraft encountered several intense air mass disturbances that produced a series of extensive and sustained vertical negative and positive loads. That caused severe horizontal oscillations before the aircraft climbed rapidly to FL448 and rolled inverted.
On the CVR tape, one of the pilots is heard saying, “Lower it, lower it…you have to chop it, you have to chop it, you have to chop it.”
“At this point, the aircraft was out of control,” the report said. “It was inverted and banked 60 degrees nose down. Then it began a rapid descent while rolling wings level. It went inverted again with a high rate of roll and continued to descend rapidly in a flat spin before hitting the terrain in a wings-level attitude.”
Inspections of both engines showed evidence of not producing thrust at the time of impact.