United Airlines Flight 227

N7030U, the aircraft involved in the accident

Flight 227, operated by a Boeing 727-22, registration N7030U,[3] departed LaGuardia Airport at 0835 Mountain Standard Time (1035 EST) for San Francisco, California, with scheduled stops in Cleveland, Chicago, Denver, and Salt Lake City. The flight to Denver was routine. In Denver a new flight crew took control of the plane: Captain Gale C. Kehmeier, First Officer Philip E. Spicer, and Second Officer Ronald R. Christensen. The flight took off from Denver at 16:54 MST.[1]

During the flight, the First Officer was flying the aircraft under the direction of the Captain. At 17:35 the plane was cleared to descend to 16,000 feet by the Salt Lake City Air Route Traffic Control Center.[1]

At 17:47, now under the direction of terminal control, the plane was cleared to approach. At 17:48, in response to the controller's request for the plane's altitude, the pilot replied "Okay we've slowed to two fifty (knots) and we're at ten (10,000 feet) we have the runway in sight now, we'll cancel and standby with your for traffic." The plane began to descend, but its rate of descent was approximately 2,300 feet per minute, nearly three times the recommended rate of descent.[1]

At approximately 17:49:30, the plane passed the outer marker 5.7 miles from the runway threshold at approximately 8,200 feet Mean Sea Level, over 2,000 feet above the normal glideslope.[1] The Salt Lake City airport has an elevation of 4,227 feet above sea level.

At approximately 1751, one minute prior to impact, the plane passed 6,300 feet; it was still 1,300 feet above the normal glide slope and still descending at 2,300 feet per minute. Around this time the first officer reached forward to advance the thrust levers to increase thrust, but the captain brushed his hand aside and said "Not yet."[1] At 30 seconds prior to impact the plane was 1,000 feet above and 1.25 miles from the runway. The captain indicated in post-crash interviews that at this point he moved the thrust levers to the takeoff power position, but the engines failed to respond properly. However, both the testimonies of the other members of the flight crew and the data from the flight data recorder indicate that the attempt to add power occurred only about 10 seconds before impact.[1]

At 1752 the plane struck the ground 335 feet short of the runway. The aircraft slid 2,838 feet before coming to a stop. The separation of the landing gear and the No. 1 engine was the result of impact loading in excess of their design structural strength. The failure of the landing gear caused the rupture of fuel lines in the fuselage. The resulting fire, rather than the impact of the crash, accounted for all 43 fatalities.[1]

This accident was blamed entirely on the bad judgment of the Captain, Gale C. Kehmeier, for conducting the final approach from a position that was too high and too close to the airport to permit a descent at the normal and safe rate. He allowed the plane to fly the final approach segment (in visual conditions) at a descent rate of 2,300 feet per minute (3 times the safe descent rate). When the plane crossed the outer marker, which marks the final approach segment, it was 2,000 feet too high.[1][2]

The First Officer, who was flying the aircraft under the Captain's direction, attempted to add engine thrust. But the Captain told him no and brushed his hands off the thrust levers. The Captain took over the controls during the last few seconds, but it was too late to avoid crashing short of the runway. The plane impacted with a vertical acceleration force of 14.7-g.[1][2]

That severe impact force broke off the left main landing gear and caused the right main gear to thrust up through the fuselage, rupturing pressurized fuel lines in the process. While the plane continued to slide down the runway on the nose gear and fuselage, pressurized fuel ignited inside the cabin, turning a survivable accident into a fatal accident. Many of the 50 people who successfully evacuated were severely burned.[1]

The CAB (Civil Aeronautics Board) accident investigation revealed that the Captain had a checkered training history. He had failed his initial jet transition training course, and was returned to flying the DC-6. Later on, he also failed to pass a routine annual instrument proficiency check.[1]