Wyoming

The aircraft was engaged in a local test flight at Greybull Airport and was carrying one passenger and three crew members. After takeoff, while climbing, the crew encountered technical problems with the right engine. The captain elected to return and initiated a turn when the aircraft lost height and crashed. All three crew members were killed while the passenger was seriously injured.

On approach to Big Piney Airport, the crew encountered bad weather conditions with low ceiling and snow. Too low, the twin engine airplane struck the ground and crashed few miles from the airfield. The aircraft was destroyed and all six occupants were killed.

While flying in marginal weather conditions (low ceiling, snow and icing conditions), both engines lost power. The pilot elected to divert to the nearest airport but the airplane lost height and eventually collided with terrain. The wreckage was found a day later. A passenger was seriously injured while six other occupants were killed.

While in cruising altitude, the twin engine airplane entered an uncontrolled descent and crashed in flames near Farson. The pilot, sole on board, was killed.

On approach to Cody Airport, the pilot failed to realize his altitude was too low when the twin engine airplane struck trees and crashed in flames on a mountain located few miles from the airfield. The wreckage was found a day later and all four occupants have been killed.

While cruising VFR on top on a flight from Scottsbluff to Eugene, the right engine failed. The pilote reduced his altitude to attempt an emergency landing and descended through adverse weather. After gears and flaps were extended, the airplane crashed in an open field. The pilot was seriously injured.

While descending to Laramie-General Herbert J. Brees Regional Airport, the pilot encountered poor weather conditions with snow falls. On final, the airplane banked left, went into a near vertical attitude then lost height and crashed in flames. The aircraft was destroyed and both occupants were killed.

Western Air Lines flight 470 to Casper and Minneapolis departed Denver at 07:03 in the morning. The airplane, on an IFR flight plan, climbed to its cruising altitude of FL220. At 07:36, following a descent to 12,000 feet, the flight crew contacted Casper approach control and advised that the flight was about 12 miles south of the Evansville Intersection. At that time, the controller cleared the flight to use the localizer back course approach for runway 25, to circle to runway 3, or to land straight in. The weather reported to the crew indicated poor visibility with light snow falling and wind 040° at 9 knots. One minute later, the approach controller advised that "runway 7/25 has been plowed. There's about a 1/4-inch of powder snow on it. Braking action reported, Convair 580, as poor. Runway 3/21 is being plowed at this time." At 07:51, Flight 470 reported at the Henning Intersection and was cleared to contact the Casper Tower. The tower controller cleared the flight to land on runway 25 and gave the wind as 030° at 8 knots. The flight was also advised by the controller that a disabled snow blower was "just west of the intersection runway 21, left side runway 25, on the edge ...." At 07:41:42, the first officer called out "thousand to go to the field." At 07:42:09, the first officer called "approaching minimums," and 12 seconds later, he called "just about at minimums." The aircraft then flew level for a few moments a t the minimum descent altitude (MDA). At 07:42:25, the first officer called the runway in sight directly below the aircraft. At that time airspeed was 150 knots and the flaps were at 25°. The first office then set the flaps at 30° as the captain initiated the final descent. The aircraft crossed the threshold at reference speed +15 knots. The aircraft touched down 2,375 feet from the departure end of the runway, about 6,306 feet from the approach end of the runway. The aircraft went off the departure end of the runway to the right of the centerline. After striking several metal stanchions in the first row of terminal bar lights, which were located 200 feet off the end of the runway, the aircraft struck a shallow irrigation ditch 280 feet off the runway end. The aircraft veered farther to the right and stopped about 800 feet beyond the departure end of the runway.

The pilot, sole on board, was completing a cargo flight from Riverton to Denver with an intermediate stop in Cheyenne. After touchdown on a wet/slushy runway, the pilot realized it was difficult to decelerate properly and decided to make a go-around. This decision was taken too late so the airplane departed far down the runway. After liftoff, the twin engine airplane struck an electric pole and several trees before crashing in a small lake. The pilot was injured and the aircraft was destroyed.

While cruising in bad weather conditions on a flight from Rock Springs to Broomfield, Colorado, control was lost. The aircraft dove into the ground and crashed in a mountainous area located near McFadden. All seven occupants were killed.