The most difficult game I ever played on CD-i. It is very unforgiving, the levels are long and arduous, but once you actually complete one the satisfaction is amazing!
The goal of each level is to break the big power dome at the end of the spacecraft. The problem is that it is protected by an electric field sustained by two generators. To disable these you'll have to destroy the other power domes first. They are only destructible by strong missiles that are sometimes dropped by enemy squadrons.
Three missiles destroy one dome, and there's roughly 4 or 5 domes that power the field generators. And then there's the final dome itself.. totalling between 15 and 18 missiles!
I've personally only recently acquired the full game (I had it on a Gold Club demo disc) so I've never seen beyond the third level. The names of the levels are mine.
By the way, this is you: