Cessna 425 Conquest I, Lone Tree, Colo., Aug. 13, 2005–The SGavit Aviation Conquest I was making a night ILS approach to Runway 35R at Centennial Airport (APA) when it crashed, killing all four occupants. Radar data showed deviations above and below the glideslope, and left and right of the localizer.
After being cleared for the approach, the 5,000-hour pilot read back the clearance, and the controller asked if he was “starting down on the altitude.” The pilot said he was. At 8,500 feet and with a groundspeed of 170 knots, the pilot told APA tower that the airplane was at the outer marker (casse). The controller reported a 500-foot ceiling and told the pilot he was “getting a low altitude, low altitude alert on you.” The pilot acknowledged that he was low but then said, “I’m back on glideslope.” That was his last transmission, although the controller tried to contact him several times.
According to the NTSB, the pilot had been in three previous accidents, once when he used the collective prematurely during autorotation when his Enstrom F28 lost power; when he failed to maintain control of a Bell 206 and it crashed into a lake; and when the Cessna 425 he was flying encountered hail and severe turbulence in cruise.
Toxicological tests on the pilot’s body revealed the presence of bupropion (taken to quit smoking) and anti-anxiety drugs. Two months before the accident, the pilot was treated in an emergency room for injuries received when arrested by the police. He told the hospital he used alprazolam (an antidepressant) and was given benzodiazepine lorazepam (an anti-anxiety drug) and the narcotic painkiller Vicodin and later filled a prescription for alprazolam.