Page:Aviation Accident Report, United Air Lines Flight 4.pdf/7

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to the Salt Lake tower frequency. At 10:57, Trip 4 contacted the tower,^[1] reported that it was five miles north,^[2] approaching the range station, and received landing instructions. The message from the tower was acknowledged by Trip 4.^[3] About one or two minutes later, the airplane crashed into the side of a hill about three miles east-northeast of the range station and 3.8 miles northeast of the airport. The point of impact was at an elevation of 5,053 feet above sea level, or about 830 feet above the level of the airport. (See map opposite this page.)

↑ The control tower operator was unable to state which member of the crew made the transmission. The contact with United's station at 10:56 had been made by Captain Brown.
↑ The first part of this message, giving tho distance as five miles, was not logged by the control tower. It was heard, however, by the person who was monitoring the range in the Communications Office. He testified that the first words were "Five north". The control tower operator testified that at the beginning of the message the crew member making the transmission said "Errr". Apparently the reception at the control tower at that moment was such that the words "Five north" were garbled into the sound described by the control tower operator. Although the previous radio message at 10:56 had given the position of the airplane as about 10 miles north of the field, the actual distance was probably substantially less. This conclusion is substantiated not only by the fact that the trip reported about one minute later that it was five miles north, but also by the fact that it had reported over the Layton marker at 10:51. Such an inaccuracy in distance is not unusual since the course south of the Layton marker lies over a portion of the lake and salt flats with no distinctive marker, for the most part, to use as a fix. It is customary for pilots to report as quickly as possible after becoming contact and to give their approximate position at the time.
↑ The message from the control tower indicated that the wind direction was between northwest and north, with the velocity gusty to 25 m.p.h., and that traffic was landing to the northwest. Trip 4 replied that it would land north.

[1] The control tower operator was unable to state which member of the crew made the transmission. The contact with United's station at 10:56 had been made by Captain Brown.

[2] The first part of this message, giving tho distance as five miles, was not logged by the control tower. It was heard, however, by the person who was monitoring the range in the Communications Office. He testified that the first words were "Five north". The control tower operator testified that at the beginning of the message the crew member making the transmission said "Errr". Apparently the reception at the control tower at that moment was such that the words "Five north" were garbled into the sound described by the control tower operator. Although the previous radio message at 10:56 had given the position of the airplane as about 10 miles north of the field, the actual distance was probably substantially less. This conclusion is substantiated not only by the fact that the trip reported about one minute later that it was five miles north, but also by the fact that it had reported over the Layton marker at 10:51. Such an inaccuracy in distance is not unusual since the course south of the Layton marker lies over a portion of the lake and salt flats with no distinctive marker, for the most part, to use as a fix. It is customary for pilots to report as quickly as possible after becoming contact and to give their approximate position at the time.

[3] The message from the control tower indicated that the wind direction was between northwest and north, with the velocity gusty to 25 m.p.h., and that traffic was landing to the northwest. Trip 4 replied that it would land north.

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