The Helipad

The roof seems to have served as the staging area for a bunch of hobbyist drone flights; there are piles of smashed toy quadcopters littered by the access door, many apparently salvaged for replacement parts. Another message waits for you wedged in the middle of a stack of half-used construction kits, haphazardly resting on top of a spare parts bin full of malformed rotors.

Propellerheads

When I'm done with you, you're not going to know which way is up.

Blades
Up to the task
Insects with a queen
Circumference sections
Dark ____
Sphere
Exsanguinated
Wild pig
Alternative to truth
Small bell sound
Give off
Always
Pennant
Committed a hockey foul
Charged particles
Not pre-taped
Heath or upland
Contemplate
Best buddies
Bottled (up)
Proper to a fault
Musical instrument type
British PDA?
Little bloodsucker
Operator