They have constant speed. No matter of the levels of engines -> Launch at the next system is the same time on level 1 as on level 10 or even on level 2000...

About the same count destroyed - The damage they're dealing is not affected by the shields.

Also - calculating the exact speed will be hard. I've found out the formula for the speed, it includes square_root(speed) and square_root(distance), also there are few constants that I still cannot get in the correct value... Also you'll need exact launch time, which you cannot see (and can guess with few seconds difference)...

This is a useful thread, but another question concerning the missiles (this may sound dumb but)... so the missiles ignore (all) shields & do direct damage to a planet's defenses armor correct?

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(Edited 7/12/12) 19:06 game time

Ignore this, I'll just fire some & find out.

Ok all defense platforms have some armor defense (the same as your Armor Tech) which effects whether the turrets are destroyed or not.

PBH