[GZG] Artillery Time of Flight

Here's one game reference I found...

"In reality, time-of-flight calculations are complicated
and apply even to long-range small-arms fire. For game
purposes, ignore the issue for small arms. For heavy weapons, it's reasonable
– if imprecise – to use a flight
time of one second per 500 yards for low-angle missions
or one second per 250 yards for high-angle missions.
Thus, it can take a long time for a round to reach its tar-
get – which might not even be there any more!"

Assuming this is anywhere in the right order of magnitude, an artillery
engagement of a target 20 km away is going to take 80 seconds (1.33 minutes)
to arrive (flight time) even if we assume near instant processing of the call.
An MRLS from 40km could take twice as long. If you're going after hover or
grav tanks that could have moved
in excess of 60 kph, your target point could well have moved 1-2 km
(and possibly not in a predictable direction). This could serve as one
limiter in artillery engagements - target mobility.

For ortillery, I'm sure the flight speed is faster, but assuming I'm dropping
rounds from LEO (160 km up if you want to be in a very poor orbit with fast
decay), you'd be looking at 640 seconds. Of course, if we throw in gravity,
etc, let's assume that's 320 seconds... 5
minutes+. Your targets have moved even further.

Of course, if you can bring in your laser batteries, arrival time is much
faster. Atmosphere will attrit their effects quite sizably though.

I guess what I'm getting at here is flight time gives defenders
chances to identify your attack, deploy multi-layered countermeasures,
or just move (intentionally or coincidentally) a sizable distance. This may
help to limit long range artillery effects in a setting where grav and AC
vehicles move quite quickly (as does PA).