Page:CAB Aviation Accident Report, Mid-Air Collision on 15 December 1959.pdf/1

This page has been validated.
File No. 2-1774

CIVIL AERONAUTICS BOARD

AIRCRAFT ACCIDENT REPORT


ADOPTED: August 16, 1960
RELEASED: August 22, 1960

MIDAIR COLLISION INVOLVING
BEECHCRAFT, C-35, N 1839D, AND WYOMING AIR NATIONAL GUARD F-86L, 52-3662,
NEAR CHEYENNE, WYOMING, MUNICIPAL AIRPORT, DECEMBER 15, 1959

SYNOPSIS

At 1520 m.s.t., December 15, 1959, an F-86L flown by Captain William E. Meckem, the wingman in a formation of two Wyoming Air National Guard F-86L's, and a Beechcraft C-35, flown by Mr. Gene A. Lewis, collided at 9,000 feet m. s. l., or 2,850 feet above the ground. The collision occurred about 4.5 miles south-southwest of the southern boundary of the Cheyenne Municipal Airport, within the airport control zone. The pilot of the Beechcraft, the only occupant, received fatal injuries. The pilot of the F-86L ejected safely but sustained minor injuries. Both aircraft were destroyed.

Shortly before the collision the F-86L flight leader made a simulated ILS and low approach during which the wingman flew in safety-observer position. Following the low approach the wingman joined in close formation. The accident occurred thereafter while the flight was proceeding to the initial point to enter the tactical pattern for landing. The Beechcraft was en route to Denver, Colorado, from St. Cloud, Minnesota, with an en route business and fueling stop at Dickinson, North Dakota.

Both flights were being made on VFR flight plans and the weather conditions in which the collision occurred were: High thin cirrus clouds; visibility 90 miles.

At the time of the collision the F-86L formation was on a heading of 110 degrees magnetic, in straight and level flight, and at a computed true airspeed of 312 knots. Analytical calculations indicate that the Bonanza was being flown on a heading of approximately 154 degrees magnetic, in straight and level flight, and at a calculated true airspeed of 139 knots. The evidence indicates that the flight conditions for the Beechcraft were constant for at least a 60-second period prior to the collision. For the first 30 seconds of the same period the F-86L formation was climbing, accelerating, and turning left. For the final 30 seconds the flight conditions of the colliding F-86L were constant as stated.

The accident took place in excellent weather conditions which, under the appropriate Civil Air Regulations and military rules, place the responsibility for collision on the pilot through visual detection and avoidance of other aircraft.