Valkyrie

Alongside the Taurox Prime vehicles the Militarum Tempestus also use the Valkyrie Transport. The Valkyrie Airborne Assault Carrier is a heavily armed Imperial Aircraft with VTOL (Vertical Takeoff Or Landing) capabilities, used to ferry troops, such as the Tempestus Scions,  to and from combat zones. Though not a helicopter, the Valkyrie is used in a similar way.

Militarum Tempestus Valkyrie
Militarum Tempestus Valkyrie on display at Warhammer World