Chaos Raptors certainly can't. They stand and plink at air units with their bolt pistols. There's a flag on each weapon type that dictates whether it can shoot at air or not.Rogue 9 wrote:Infantry flamers can shoot at air units; what makes you think they can't? I had a squad of Shoota Boyz with burnas shooting at a Land Speeder Tempest just last night.
(Personally, I think many fewer things need to be able to shoot at air units, certainly nothing smaller than a Heavy Bolter. I'm tempted to grab the mod tools and fiddle with that, and other things, it would make them less rubbish.)
Really though, I wish air units worked like they do in Epic. You build them but they stay off board unless they're on a specific mission. (Bombing/ground strike missions you specify with a button like the DE powers, air to air missions launch themselves as soon as an enemy plane is sighted, and each force should have all it's air units available)