Okay so I am back at my computer now.

Minizap gives the AIM-120B a 1.27nm launch range from 1.4M at 49000ft against a target going 2.5M at 75000ft. At this point it is losing speed.

Now we will discuss differences between the AIM-120B in minizap and the AIM-120D in my simulation

Fins.

The AIM-120B had the fullsize fins. In the AIM-120C/D the fins are clipped to fit more of them inside the bay of the F-22 (only 4 AIM-120A/B would fit). For the AIM-120A/B the total wingspan is the 21in seen in Minizap and a fin side area of .6966ft^2, all as shown above. The AIM-120C/D has a total wingspan on 17.54 inches and a side fin area of roughly .479ft^2 front and .771ft^2 rear for a .625ft^2 average.

Rocket Motor.

The AIM-120B in Minizap has a 108lb motor with a 230 ISP and a 0.7s boost at a thrust rating 2.6 times the sustain charge and a sustain charge that lasts 10.3s. Doing the math that comes out to a 5329lbt boost and a 2050lbt sustainer. The problem is we know that the AIM-120 does not have a dual pulse motor. We also know the rocket motor was upgraded at the C-5 or C-7, I can't remember which right now. My AIM-120D has a 135lb motor with an ISP of 265 that only burns at one setting for 8 seconds. This gives a thrust rating of 4472lbt.

If I alter the Minizap Calculation with my missile parameters and change nothing else I get a 7.2nm launch range to max pursuit.

If I step through this in 1 sec increments (like my simulator) I see that it takes 6 seconds for the missile to point to the loft angle and that after 8 s it has only climbed to 53,300ft and 4.96M.

My simulator has the AIM-120D reaching it's climb angle in 3 seconds and after 8 seconds being at 58,900ft and 6.2M.

Over the next several seconds in Minizap the missile is pulling 3-9G while in my simulation the missile is coasting at 0 G, pure ballistic flight profile. The minizap missile climbs to 101,000ft with an apogee speed on 2.5M in 1 second increments, my sim has it coasting to 109,000ft at 4.4M.

I cannot speak to minizap, but I am modeling standard atmosphere from sea level to 130,000ft. I am also using a CFD based wave drag profile for missiles that shows that drag coefficients at and above Mach 3 are the same as the subsonic values.

my current guidance algorithm has the missile coasting until in reaches 75,000ft at M4+ some ways behind the MiG and then leveling off and coasting into the back of it. That is odd. I wonder if the aimpoint was too far out for the glide logic to kick in right.