Sorry for being off topic shortly, but...
semiactive needs continous transmission IRL - that means - radar beam has to move damn fast, or be aimed at one only plane (locked). It can be locked in "scan-mode" only with modern phased array type of radar - when you move your beams digitally, you can move them as fast as you want... but missile is prevented from doing so - it would have problems with choosing the right target...
That much, that (nearly) good.
"Scan-while-track" was available in the "pre-phased-array" radar era already.
It depends on the movement rate of your desired target.
When the "illuminating" radar "leaves" the target, the semiactive missile will just run straight until it fetches the illuminating signal again.
As long as the target didn't leave the receiver cone in that time, everything's fine.
"Cone"... that's the second thing to take care of:
The semiactive missile might either have a conical scan seeker or a monopulse one, both having quite different characteristics and both requiring different types of illumination with different types of possible jamming. Too much stuff to discuss here, a nice overview is given at
this address.
active missile needs only initial lock. it has its own radar. HOWEVER - this radar (IRL) has only short range - not BVR - so you launch it as semiactive, wait until it is locked by missile in-air and then lock off and can freely fly away.
Nope.
Active radar guided missiles are either using command link guidance or inertial mid-course guidance.
The launching aircraft doesn't illuminate the target, it uploads an initial flightpath to the target and/or updates the path via datalink until the missile can acquire a successful lock by itself.
when I pull and then let the stick to neutral, it takes quite a while for elevators to return to normal. Was that intention?
Welcome to the Fly-By-Wire system.
Your stick doesn't "directly" control the surfaces.
When you move your stick, you give command for how many Gs you want to pull and/or how fast you want to roll/yaw.
The computer takes care about the required control face positions then.
As such, when you command goes from "full Gs" (pull all way through) to "1G" (stick centered), the elevator will not go back to neutral immediately (that would result in a short burst of negative Gs), but will move back to neutral in a given time according to your current flight condition (rule of thumb: The slower you are, the faster your controls will move).
Best regards - Mike