The F-16 pilot flying alone over South Carolina was told 40 seconds before the collision that traffic was straight ahead, two miles away. The Air Force officer had never heard an initial traffic alert so close, he later told investigators. He scanned the sky “aggressively” but did not spot the Cessna 150 over Moncks Corner until a fraction of a second before the collision that claimed two lives. Technology that could have given each pilot ample warning was absent from both aircraft.
Source: aopaPilots unaware before midair