1940 – Nov 4, United Airlines Trip 16 flies into Bountiful Mt. NE of Centerville, UT –all 10
Compiled by Wayne Blanchard; last edit 10-12-2024 for upload to: http://www.usdeadlyevents.com/
–10 Civil Aeronautics Board. Report…of the investigation…United…NC 16086…Nov 4, 1940.
Narrative Information
Civil Aeronautics Board. Report…of the investigation…United…NC 16086…Nov 4, 1940:
“An accident involving aircraft NC 16086 while operating in scheduled air carrier service as Trip 16 of United Air Lines Transport Corporation (‘United’) occurred in the vicinity of Centerville Utah, on November 4, 1940, at approximately 4:42 a.m. (MST) resulting in the destruction of the airplane and fatal injuries to everyone on board….” (p. 1.)
“On the flight in question, the flight crew consisted of Captain Howard M. Fey and First Officer Thomas E. Sandegren….” (p. 5.)
“The flight plan prepared for Trip 16 by Captain Fey at Oakland and signed by him, First Officer Sandegren, and Philip Showalter, United dispatcher at Oakland, provided for a flight from Oakland to Salt Lake City with stops at San Francisco and Sacramento, California, and Reno and Elki, Nevada….
“Trip 16 departed Oakland at 10:20 p.m. (MST)…proceeded without incident to Reno, departing from that point at 1:00 a.m., cleared to Salt Lake City….” (p.11)
Conclusion…Findings
“….(8) Trip 16 first arrived over the Salt Lake radio range station at 3:40 and remained in that vicinity at an altitude of approximately 14,000 feet until shortly after 4:26, when Captain Fey began a let-down-through procedure.
“(9) During the period Trip 16 operated in the vicinity of Salt Lake City, two-way radio communication between United’s ground station at Salt Lake and the pilots of Trip 16 was made impossible for substantial periods of time due to severe static, and at times such static interfered with reception of radio range signals by the pilots of Trip 16.
“(10) During the period Trip 16 operated in the vicinity of Salt Lake City the weather conditions at the Salt Lake City airport were extremely variable with ceilings ranging from 400 feet to 2700 feet and visibility ranging from 5/8 of a mile to 9 miles with light to moderate snow flurries and with variable northwesterly surface winds ranging from 3 to 7 miles per hour.
….
“(12) Shortly after 4:26, Captain proceeded northward from the neighborhood of Salt lake City and began his descent [which required a turn to the east and then south to SLC between Salt Lake to the west and a mountain range to the east].
“(13) Captain Fey began his descent during a period of time when, because of heavy static, he was unable to hear radio range signals and thus without definitely locating his position with respect to the normal north leg of the Salt Lake City radio range; and after he had emerged from the area of severe static proceeded north receiving ‘A’ or ‘A twilight’ signals.
“(14) In so doing, he failed to comply with well-established range procedures designed to permit the execution of let-down-through procedures with maximum safety.
“(15) Captain Fey began a standard procedure turn at a point which bears approximately 349 degrees magnetic from the Salt Lake City station of 17 degrees east of the normal position of the north leg of the Salt Lake City range [in other words off course to the east where the mountain range was].
“(16) He assumed his reciprocal heading at a point near Kaysville, Utah, at which time he was receiving the visual indication of the Layton marker and proceeded on that heading for not more than three minutes until the airplane struck the side of Bountiful Mountain.
….
“(19) During the time Trip 16 was operating in the vicinity of Salt Lake City and for a substantial period prior thereto, the Salt Lake radio range was functioning abnormally [my emphasis]; and, during the period between 4:40 and 4:50, the north course had swung so far to the east as to destroy its usefulness for purposes of let-down-through procedure.
“(20) The malfunctioning of the Salt Lake range resulted from the effect of atmospheric conditions upon some defective component of the range equipment.
….
“(22) The Salt Lake radio range was malfunctioning to such an extent during the early morning of November 4, 1940, that the monitoring operators at Salt Lake City, Plymouth, and Tintic, notwithstanding intermittent heavy static, could, by the exercise of reasonable diligence, have detected such malfunctioning in time to have permitted the issuance of a general warning prior to the accident since the United ground station was able to contact Captain Fey as late as 4:41 a.m.
“(23) The malfunctioning of the Salt Lake City range was not detected by the monitoring operators at Salt Lake City, Plymouth, and Tintic, until 5:37, 6:46, and 7:03 a.m. respectively.
Probable Cause
“On the basis of the foregoing findings of fact and upon all of the evidence available at this time, we find that the probable cause of the accident to aircraft NC 16086 United’s Trip 16) on November 4, 1940, was the malfunctioning of the Salt Lake radio range and that substantial contributing factors to the accident were:
“(1) The failure of the communications operators at Tintic, Plymouth, and Salt Lake City, Utah, whose duty it was to monitor the range, to detect its malfunctioning and immediately notify those concerned; and
“(2) The failure of the pilot of Trip 16 to follow to the fullest extent established radio range technique in accordance with the requirements of the procedure established by United and approved by the Civil Aeronautics Administration.” (pp. 112-115)
Source
Civil Aeronautics Board. Report of the Civil Aeronautics Board Of the investigation of an accident involving civil aircraft of the United States NC 16086 which occurred near Centerville, Utah, on November 4, 1940. 124 pages. Accessed 10-12-2024 at: https://rosap.ntl.bts.gov/view/dot/33018