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Flak

[Content from Rule Book page 47 to 48.]

Some units are noted as being 'flak' units. Flak units are specially designed to be able to attack flyers. A detachment containing flak units may be placed on alert when flyer missions are being declared. If you want to do this, mark the detachment with an Order dice showing they have special orders ('!').

Overall, using flak vehicles seems to be a waste of time unless you're protecting an immobile target like an artillery battery. In order to make flak units a bit more useful the following rule now applies.

Flak units may Snap Fire at flyers and drop pods at up to their maximum range, no special orders are needed. Note, however, that any special abilities the flak unit has do not apply to snap shots (i.e the Fire Prism's Anti-tank ability). If on special (!) orders the flak unit works as described in the rules.

By way of a clarification it is possible to place a detachment on special orders and have the flak units fire at flyers and the artillery units prep barrage. The intention to use a preparatory barrage must be stated at the time when the order dice is placed on the flak to put it on alert.

[From Firepower #1 page 13.]

Flak units on special orders may not move or fire in the Shooting phase, they fire at flyers in the Movement phase instead. Other units in a detachment on special orders count as being on Overwatch, so they can move 5cm and re-roll any misses in the Shooting phase.

A flak unit on special orders can shoot at enemy flyers if any part of their flight path is within the unit's range. Roll 1 D6 per point of Firepower the flak unit has. Each dice that equals or beats the flyer's Armour value scores a hit. A flak unit can split its firepower amongst several flyers if you wish. Once a flak unit has rolled 1 D6 for each point of its firepower it has completed all of the firing it can do in one turn.