Denver-Stapleton

On July 11, 1961, at 1136 M.S.T., a United Air Lines DC-8 crashed during its landing roll at Stapleton Airfield, Denver, Colorado. None of the 122 occupants was severely injured as an immediate result of the impact; however, there were 16 passenger fatalities as a result of carbon monoxide poisoning when the aircraft burned. One other passenger, an elderly woman, broke both ankles during evacuation of the airplane and later succumbed to shock. In addition, the driver of a panel truck, which the aircraft struck after leaving the runway, also suffered fatal injuries. After experiencing hydraulic difficulties following takeoff from Omaha, Nebraska, the crew of N8040U continued the flight to Denver, using procedures set forth in the flight manual for abnormal hydraulic situations. When the flight arrived in the Denver area, preparations were made for landing. The ejectors were extended hydraulically, however, when an attempt was made to extend flaps to 25 degrees the hydraulic pressure dropped to zero. The hydraulic system selector was then placed in the No. 3 position (flap and gear downlock), and the approach was continued. After touchdown, the throttles were placed in the idle reverse thrust position and when power was applied, an uncontrollable deviation from the runway occurred.

The crew was completing a cargo flight from Denver-Stapleton to Ogden-Hill AFB, Utah. En route, while cruising at an altitude of 8,700 feet in poor weather conditions, the airplane struck the slope of a mountain located near Fort Collins. The wreckage was found few hours later and both pilots were killed. At the time of the accident, weather was poor with icing conditions and turbulences. It is believed the airplane lost altitude until it impacted terrain.

Shortly after takeoff from Lowry AFB, while climbing, the aircraft suffered a loss of power on all engines. The captain decided to divert to the nearest Airport, Denver-Stapleton. On final, the airplane stalled and crashed in flames one mile short of runway 17 threshold. All 21 occupants escaped while the aircraft was destroyed by a post crash fire.

United Air Lines operates a Flight Training Center at Denver, Colorado, to train applicants for first officer positions with the company. The crew of United Trainer 16 consisted of Senior First Officer Jordan D. Kocher, who had been designated by United Air Lines as captain and instructor, and Trainee First Officers Laurence G. Wilson and Wayne C. Moen. The flight departed Stapleton Airfield at 0655LT. The 0628 weather conditions, upon which the crew had been briefed, were ceiling measured 15,000 feet, visibility 25 miles, and wind northwest 14 knots Ceiling and visibility were unlimited at the time of the accident, with the wind northwest 16 knots. No radio contacts were made by United Trainer 16 after reporting departure time. It was cleared for a training flight of four hours’ duration within a 25-mile radius of Denver Captain Kocher occupied the left pilot’s seat at takeoff. Upon departure, the aircraft load, in addition to the crew, was 820 gallons of gasoline, full oil tanks, and 650 pounds of sand ballast tied down in the rear baggage pit. The load was properly distributed with relation to the aircraft’s center of gravity, and the 22,910-pound gross weight at takeoff was within allowable limits. Witnesses reported that at between 0720 and 0725 the aircraft was seen to stall, enter a spin, and strike the ground in a diving attitude before recovery was effected.

The crew performed their “before takeoff check", found all components of the aircraft to operate normally, and then, at 0329, rolled onto the runway for takeoff. From the tower, the aircraft appeared to accelerate slowly and to take an excessively long period of time to become airborne. The pilots stated that the engines operated normally, developing 45-inch hg. of manifold pressure and 2700 RPH (revolutions per minute), but air speed increased slowly. Between 90 and 100 miles per hour, and just before the end of the runway was reached, the aircraft was pulled off the runway by Captain Robins as he applied back pressure on the control column. After take-off, the highest air speed attained was between 100 and 105 miles per hour. The landing gear, control was placed in the “up” position,when the flight became airborne, and a climb was made to about 100 feet. During the climb, the aircraft shuddered severely. Altitude was lost, and the aircraft struck an obstruction light on the top of a 40-foot electric light pole which was 1,910 feet south of the end of the runway. The aircraft struck three more pole, then touched ground and skidded for 350 feet. It came to a full stop 2,791 feet from the south end, and in line Runway 17. The crash landing was made in an alley way of a residential district located between Stapleton Air Field and the Lowry Air Force Base, which is located 1-1/4 miles south of Stapleton. In addition to striking the electric light poles, the aircraft knocked down several fences, a small tool shed, and collided into two parked automobiles. Crash and fire equipment which was dispatched from both the Stapleton and Lowry Airports and the city of Denver arrived promptly. Partly as a result of their precautionary action, no fire occurred.

The aircraft departed Denver at 1602 for Grand Junction. The crew, all employees of the Civil Aeronautics Administration, consisted of Fred L. Snavely, pilot; Warren L. Lungstrum, copilot; and Ross C. Brown, observer. Over the route to Grand Junction a check was to be made by these men of the VHF (very high frequency) airway facilities to determine whether they were operating normally. According to the flight plan, the flight was to proceed over Red Airway 6 at an air speed of 150 mph. Though only 2 hours were required for the trip, 8 hours supply of fuel was carried. Information supplied to Copilot Lungstrum at the Denver United States Weather Bureau Office was to the effect that clear weather conditions existed generally over the intended route. Over Fraser, Colorado, located approximately 50 miles west northwest of Denver, however, broken clouds were reported. Since this layer of clouds was only 2,000 feet in depth, with tops at 13,500 feet above sea level, it appeared that a cruising altitude of 14,000 or 15,000 feet would be high enough for the flight. Winds at that altitude were from the northwest at 50 mph. Weather Bureau personnel advised that these winds would result in considerable turbulence. Take-off was accomplished at 1602. Twenty-two minutes later, at 1624, the CAA communication station at Denver received a position report from the flight that it was at an altitude of 14,500 feet, 500 feet over the top of clouds, and 20 miles west of Denver. The flight also reported that they were experiencing severe turbulence. Since the flight plan specified that the trip would be made in accordance with visual flight rules, and since the position report indicated that the aircraft was being flown over the top of clouds, the flight was requested at the termination of their 1624 position to verify whether they were actually proceeding in accordance with visual flight rules. A response in the affirmative was received. About one minute after the 1624 report the CAA communicator at Cheyenne, Wyoming, called NC206 and asked for a check of his station’s radio transmission. NC206 responded, “Read Cheyenne Radio loud and clear.” The communicator then asked for a position report from NC206, and the flight replied, “We are approximately. . . .” The remainder of this message, received shortly after 1625, was garbled and faded. The Cheyenne communicator attempted to contact the flight again but was unable to do so. Since interference to radio transmission could have resulted from the mountain ranges between Cheyenne and the aircraft, and since the Cheyenne communicator had overheard the report of severe turbulence, he presumed that the crew was completely occupied in flying the aircraft, and that either they had not heard the last transmission or were too busy at the time to acknowledge. Accordingly, he placed no significance on the failure of the flight to reply. A request had previously been made by the communication station at Eagle, Colorado, for the flight to check the radio transmission of that station. Since Eagle Radio did not receive any calls from NC206, the station called the flight at 1645. No reply was received. Repeated calls were made by the communicator at Eagle on all available frequencies at three-minute intervals until 1735. Then the station requested information concerning the flight from Grand Junction Radio, but neither Grand Junction Radio nor any other radio station on the route had received a call from NC206 since 1625. At 1825, 23 minutes after the estimated arrival time of NC206 at Grand Junction, an emergency was declared.

While on final approach to runway 21 in poor weather conditions, the aircraft was too low and hit a hill located less than one mile from the runway threshold. The aircraft was destroyed and both crew members were killed.