Air attacks against "hidden" units

[Brett Nicholson]

Can air-strikes be made against hexes suspected of containing enemy units? Rule 15.11 states that "Aircraft may attack any HEXES on the board", note that is hex, not necessarily unit. In the 'Guadacanal' scenario book it says that fire against "hidden" units is reduced by one column for DF and bombardment, whether the hex is actually occupied or not. Aircraft fire is conducted on the DF table so it seems that they would qualify. I didn't see anything in the annotated rules mentioned as to whether or not this can be done. Inquiring minds want to know!