Has to be said that a lot of its bad reputation wasn’t from the missile itself, but how it was employed.
-In every purpose-built interceptor using it, the Falcon sat in a nice, enclosed, climate controlled internal weapons bay until it was time to be fired. It never had to deal with dust or pebbles getting kicked up into it, or the freezing cold air for extended periods of time. Reliability in Vietnam was also worsened by the hot and humid air alongside crude maintenance practices, which impacted the Sparrow even more (and led to its ABYSMAL reliability rates). This isn’t the end of it either, as meeting an enemy fighter in Vietnam was also very rare and those Falcons could spend several missions going from hot and humid to freezing cold several times;
-The Falcon-armed interceptors enjoyed a great deal of automation made possible by their intended mission: the Hughes MA-1 FCS would automatically choose the best intercept course (and steer the plane accordingly), pre-align the seeker, cool down the seeker, fire it at the optimal range. In the F-4 this all had to be done manually step by step, and coolant was limited as it was stored in the pylon instead of being provided by the internal weapons bay;
-The AN/APQ-120 in the F-4 also wasn’t made specifically to work with the Falcon (unlike the integrated Hughes FCS) and communication wasn’t exactly 1:1, though I wish I knew more. Lacking all the automation features it of course wasn’t be able to steer or instruct the pilot on the optimal course or when to fire it, and thus was left to whenever the pilot felt that he was in range;
-The impact fuse was chosen for a very specific reason: bombers are big and easy to hit, despite its smaller warhead when compared to Sidewinder, it had a much greater kill probability than it;
-All said and done, it was a much superior missile to the Sidewinder once it was in the air. Faster, greater range, greater G limit, a much superior seeker with limited all-aspect capability (versus none from the Sidewinder) and a limited degree of LOAL possible - the MA-1 could instruct the Falcon to steer to a given heading and elevation and point its seeker at a specific location after launch… within pretty strict limits, to get around the issue of fuselage blanking.
