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In the little rulebook (the one that comes with the starter set) it says on page 71 under moving skimmers, first paragraph that "Note that a skimmer must be set down on the table and left in place at the end of its move - it cannot be left hovering in midair" Is that a deathblow to FoF?
I have to concur with Lost Nemesis conclusion. the only time you would be asked to take your skimmer off of its base is if it voluntarily landed or was immobilised. Even that, most players are pretty lenient especially considering the relative weakness the clear bases have and tendency of them breaking.
- Never underestimate the power of human stupidity.
Keep reading to the bottom of that page. Under "Shooting at Skimmers" it says that it is not permitted to remove the flying stand unless the skimmer is wrecked or immobilised. Combine these two statements and it shows that what is meant by the first statement is that you do not remove the base once you've finished your movement.
But, if tau vehicles don't move, they may choose to stop counting as a skimmer until they move again, due to landing gear.
(The flight stands mentioned by the LOBot seem very appealing to me though... Acrylic Flight Stands from Back2Base | Librarium Online I was going to say they seemed a bit pricy, but... that is in aussie dollars... though, then I'd need them delivered... hmm...)