Status:	Final
Date:	Saturday 17 November 1951
Time:	10:14
Type:	Douglas C-54D-10-DC (DC-4)
Operator:	Overseas National Airways - ONA
Registration:	N79992
MSN:	10832
First flight:	1945
Crew:	Fatalities: 3 / Occupants: 3
Passengers:	Fatalities: 0 / Occupants: 0
Total:	Fatalities: 3 / Occupants: 3
Aircraft damage:	Damaged beyond repair
Location:	Oakland Range, CA (   United States of America)
Phase:	Approach (APR)
Nature:	Training
Departure airport:	Oakland International Airport, CA (OAK/KOAK), United States of America
Destination airport:	Oakland International Airport, CA (OAK/KOAK), United States of America

Narrative:
An Overseas National C-54D (N79992, msn 10832) took off from Oakland at 08:20 on a captain's instrument competency check. At 09:23 the flight was given clearance to make a practice range approach and to remain above 1500 feet. At 09:35 a California Eastern C-54 (N4002B, msn 10474) took off from Oakland for a similar check-flight.
The two C-54 aircraft approached Oakland Range (located 0,2 mile NE of runway 15) at 3000 feet; the Overseas National aircraft on a 124° heading at a speed of 140 mph, the California Eastern plane on a 75° heading at a speed of 170 mph. Both aircraft continued until they collided. The empennage of the ONA aircraft was torn off and the plane crashed on a highway and caught fire. Eleven people on the ground were injured. The other C-54 was able to make an emergency landing at San Francisco Airport.

PROBABLE CAUSE: "The failure of the Overseas safety pilot and/or his observer to observe and so avoid the other aircraft and the failure of California's safety pilot to carry a qualified observer aboard the aircraft to insure adequate field of vision."

Mid air collision
Loss of control

» CAB File No. 1-0098
» ICAO Circular 38-AN/33 (21-24)