jungle

the problem. Theories aside, if you do something an aircraft is not designed for it will bite you.



Investigation
The investigation into the accident focused mainly on information contained on the flight data recorder and the cockpit voice recorder. This is the official version of events as determined by that investigation.

The two pilots were exploiting the performance of the empty CRJ-200 on the ferry flight. The pilots decided to test the limits of the CRJ, and join the "410 Club," referring to pilots who pushed CRJs to their maximum approved altitude of Flight Level 410 (41,000 feet).

The incident started when the pilots performed several non-standard maneuvers at 15,000 feet, including a pitch-up at 2.3g (23 m/s²) that induced a stall warning. They set the autopilot to climb at 500 ft/min to FL410. This exceeded the manufacturer's recommended climb rate at altitudes above FL380. In the attempt to reach FL410, the plane was pulled up at over 1.2g, and the angle of attack became excessive to maintain climb rate in the thinner upper atmosphere. After reaching FL410, the plane was cruising at 150 knots (280 km/h), barely above stall speed, and had over-stressed the engines.

The anti-stall devices activated while they were at altitude, but the pilots overrode the automatic nose-down that would increase speed to prevent stall. After four overrides, both engines experienced flameout and shut down. The plane then stalled, and the pilots recovered from the stall at FL380 while still having no engines. At that altitude, there were six airports within reach for a forced landing. This led the pilots to pitch nose down in an attempt to restart the engines, which requires a dive sharp enough to attain the required 300 kt for a windmill restart to make the blades in the turbines windmill at 10% N2.

However, those blades and the gears expanded and the metal scraped on each other when the engine overheated.[citation needed] Thus, when the engine cooled, the assembly did not match anymore and the blades could not rotate freely. The crew ended the dive when they had reached 230 kt but the blade rotation rate had not climbed above 2% N2. Since they were too high for an APU start, the ram air turbine (known as an Air Driven Generator on Bombardier products) was deployed to power the aircraft, and the crew donned oxygen masks as the cabin slowly depressurized due to loss of pressurization air from the engines.

The crew glided for several minutes. The crew then tried to restart engines using the APU at 13,000 ft. This was again unsuccessful. They then declared to Air Traffic Control (ATC) that they had a single engine flameout. At this point they had four diversion airports available to them. After continuing unsuccessfully to attempt to restart the engines for over 14 minutes, during which period much altitude was lost, they declared to ATC that they had in fact lost both engines.

Unable to reach the assigned diversion airport, Jefferson City Memorial Airport, they crashed six minutes later outside Jefferson City, Missouri, behind a row of houses (the 600 block of Hutton Lane — two-and-a-half miles short of the airport), and the plane caught fire. Both pilots were killed. There was some damage to houses and a garage, but no one on the ground was hurt.
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