Ummm, as an ex-fighter guy, we extensively used our air-to-air radar to enhance see and avoid looking for possible threats from aircraft flying VFR. As Kirk has pointed out, we also used to interrogate Mode three 1200 squawks looking for traffic that might not be displayed on our pulsed Doppler radars due to the velocity notch around zero groundspeed.

Now, in a MOA, restricted area or warning area where we might be using the radar for other more tactical application, looking for possible traffic was not a priority. But yeah, once flying to and from? That radar is a major source of situation awareness of opposing traffic.

Now to this specific incident, given the description of a broadside impact, and given the slow speed of a C150 on climb out, it is highly unlikely this aircraft would have appeared on the fighter radar, it would have been considered in the "ground clutter" and not displayed. And while flying under ATC, practicing instrument procedures, the Pilot may have been less than vigilant in his see and avoid responsibilities. That said, a C150 appearing as a non moving spot on the canopy (definition of collision course) doesn't catch the eye movement or size wise until very late...

Squeaky
USFA 83