Gaunt's ghosts stuff, in The Guns of Tanith.
Well, phantine skyborne is a special branch of service in the Imperial Guard, coz they operate differently.
While others go into the warzone with a bang, the Skyborne going into war is just like going into a picnic. They bring lots of stuff.
Coz when you jumps out of an airplane into friggin hell, there is definitely no chance in the warp that you can enjoy the privilege of Express Chimera / Dial E - emperor for ammo service. You bring all your kits, airborne style. ^^" heheh.
Instead of the good old chute, they uses the Grav chute that manipulate existing gravity so they can land from a great height. Instead of those space marine bulky type (Guardsman will be crushed like sardine under the weight) they uses the Lucius forge world grav chute that is compact and easier to move.
the las gun is a spacial one, uses foldable wire stock and infra red scope (I hope so, Emperor bless the Adeptus Machanicus).
Finally, that slogan/motto is my lame ass imagination but it sure beats the "Out of the clouds and kick some ass". ^^"