1961 — July 11, United Flight 859 Landing Crash and Fire, Stapleton AP, Denver, CO– 18
— 18 AirDisaster.Com. Accident Database. Accident Synopsis 07111961
— 18 CAB. AAR. United Air Lines… Stapleton Airfield, Denver, Colorado, July 11, 1961.
— 18 Kimura. World Com. Aircraft Accidents, 3rd Ed.., 946-1991, Vol. 1, 1994, p. 2-5.
Narrative Information
Civil Aeronautics Board: “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 N 8040U 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 down lock), 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….
“As the aircraft skidded across the grass strip between the runway and new taxiway, the second officer unbuckled his seat belt and started back to the passenger loading door, anticipating an emergency evacuation of the aircraft. A violent lurch of the aircraft pitched him into the observer’s seat but he regained his footing and proceeded to the forward passenger loading door, arriving there about the time the aircraft came to rest on its belly. After opening the door and installing the emergency slide he began to help passengers to the exit. He noticed a fire burning on the left side of the aircraft and the cabin beginning to fill with smoke.
“The first officer and two male passengers jumped to the ground from the forward loading door and held the uninflated slide to assist other passengers out of the aircraft. Meanwhile, the captain and second officer were making repeated trips into the smoke-filled cabin to assist passengers to the exit. Finally the captain and second officer could find no other passengers in the first-class section. By this time the flames completely covered the front passenger loading door.
“As previously mentioned, the crew had alerted ground personnel of the abnormal situation. Under such circumstances the airport firefighting personnel are alerted and the fire trucks take up standby positions on the ramp near the passenger terminal. In accordance with this plan the fire trucks took up these positions. The aircraft came to rest approximately one mile from this point. There was substantial variation in the estimated elapsed time between the accident and the firefighting personnel being in position to fight the fire. Eyewitness estimates of the elapsed time prior to the arrival of the first fire trucks varied from 5 to 10 minutes, and up to 15 minutes before any effective equipment was in position.
“The members of the Stapleton Airfield firefighting crews stated that their equipment was moving to the airplane before it had come to rest and that foam and fog were being applied to the fire within one to two minutes. The Aurora Fire Chief, who had been notified by the Aurora Police Department, said his equipment arrived at the scene about 6 to 8 minutes after the crash. He also said that when he arrived the Stapleton crew already fighting the fire. Lowry Air Force Base and Buckley Field had been advised of the accident immediately and had dispatched their firefighting and rescue personnel to the scene. Their equipment arrived within about 15 minutes and also assisted in fighting the fire. It was estimated that it took approximately 30 minutes to bring the fire under control.
“The extensive fire after impact destroyed a major portion of the left wing and left side of the fuselage from the cockpit area aft to the rear passenger loading door. In addition, the entire inside of the cabin was gutted. The fuselage area aft of the rear passenger loading door was crashed inward, due to contact with a surveyor’s panel truck parked 300 feet from the runway centerline. In addition, the force of this impact distorted the lower frame of the loading door and rendered this exit inoperable from the inside….
“From all the evidence it is concluded that in the subject case the first officer applied reverse thrust without checking to see if the amber thrust reverser indicator lights were on. The normal procedure for reversing requires that these lights be on before increasing power for reverse. Subsequent to the accident the need for close monitoring of these lights was re-emphasized by the company.
“The crews original diagnosis of the trouble was correct in that an abnormal hydraulic situation existed. Very shortly after departing the holding pattern at Strasburg en route to runway 26L, the abnormal situation abruptly developed into an emergency condition without the crew being cognizant of the fact. This occurred when 25 degrees of flap was selected with the hydraulic selector in the No. 1 position. When the complete loss of hydraulic pressure occurred, the crew should have been aware that an emergency situation had developed and that a normal landing could not be expected….
“The Board determines the probable cause of this accident was the asymmetric thrust which, during a hydraulic emergency, resulted from the failure of the thrust reversers on engines Nos. 1 and 2 when reverse thrust was selected. A contributing factor was the failure of the first officer to monitor the thrust reverse indicator lights when applying reverse thrust….
“Subsequent to this accident, extensive modifications to the DC-8 hydraulic system were made mandatory in an Airworthiness Directive issued by the Federal Aviation Agency. Another Airworthiness Directive required that all DC-8 aircraft be equipped with a throttle thrust brake interlock to prevent unintentional application of asymmetric reverse thrust….” (CAB. AAR. United Air Lines… Stapleton Airfield, Denver, Colorado, July 11, 1961.)
Sources
AirDisaster.Com. Accident Database. Accident Synopsis 07111961. Accessed at: http://www.airdisaster.com/cgi-bin/view_details.cgi?date=07111961®=N8040U&airline=United+Airlines
Civil Aeronautics Board. Aircraft Accident Report. United Air Lines, Inc., Douglas DC-8, N 8040U, Stapleton Airfield, Denver, Colorado, July 11, 1961. CAB, 7-16-1962. Accessed at: http://dotlibrary1.specialcollection.net/scripts/ws.dll?file&fn=8&name=*P%3A%5CDOT%5Cairplane%20accidents%5Cwebsearch%5C071161.pdf
Kimura, Chris Y. World Commercial Aircraft Accidents 3rd Edition, 1946-1993, Volume 1: Jet and Turboprop Aircrafts. Livermore, CA: Lawrence Livermore National Laboratory, Risk Assessment and Nuclear Engineering Group. 4-11-1994, p. 2.5.