Multirotor Design Concepts and Prototypes
This intends to catalog the hovering multirotor variants. Does not include VTOL vehicles which can achieve an unpowered glide, which are covered in Hybrid tilting aircraft.
 Standard Designs
- X4 - A typical quadrotor, quadrocopter, quadcopter, or just quad, with all props mounted on the ends of arms arrayed radially outward from a central hub, pulling upwards at opposite ends of the craft; May be switched between 'X' or '+' configuration (with one arm leading 'forward') in software
- Hexa - A typical hexacopter, or just hexa, with six arms arrayed radially outward from a center point
- Y6 - A type of hexacopter with three arms arrayed radially outward from a center point, and one motor mounted at the end of each arm pointing up, and one pointing down
- Octo - A typical octocopter, or just octo, that follows the pattern of one motor per arm arrayed radially. Common on 'heavy lift' designs that re-use parts from smaller part inventories. May have independent radial arms or a branching structure
 Less Common Designs
- X8 - An octocopter that uses four arms, with motors arranged coaxially pointed up and down
- H8 - An octocopter that uses two parallel rails, each containing four rotors, attached to the core at multiple points. Generalizable (less commonly) to H6, H10, or H12 designs
- Asymmetric designs - Any of these can be stretched and skewed, possibly with the central core offset, to create a design that offers clearance in the front of the craft for a forward-looking camera un-obstructed by propellers.
- Tricopter - a servo-controlled third arm corrects for yaw
- Bicopter - Gyroscopic roll/pitch coupling allows full steering in this two-rotor craft with a steeply cambered, fixed tail
 Rare Designs
- Y4 - Like a tricopter, but the servo arm has a pair of coaxial rotors
- V-Tail Quad - A quad with a defined forward area and a 'tail', having two props close together, and canted at an angle in order to couple the throttle with yaw control more closely.
- Hashcopter - An X8 that uses four long rods to make a potentially very strong, simple frame in the shape of a #
- Variable Pitch Quad - Collective pitch props mounted on four brushless motors allow for a significantly faster maneuvering response
 Built-Prototype Concepts
- ICE Quadrotor - mounts a piston engine in the central core with a transmission reaching out to four collective-pitch props.
- Hg3.2 the first hybrid variable pitch quad - Joseph D'Angelo & Roberto Navoni1
- Astracopter Endurance Work - a copter that stays in the air considerably longer than normal by using its battery in stages and shedding spent stages to the ground. Achieved 141 minutes in one test run.
- E-Volo Volocopter - an attempt at scaling up the electronic multirotor concept to human-carrying scale, claims the first manned flight on one of their prototypes, a 16-prop model with an exercise ball as landing gear
 On-Paper Vehicle Concepts
- Variable-Fixed Hybrid Y8 - Uses four big, wide fixed-pitch slow props for lift and slow adjustments, and four small high-RPM collective-pitch props for fast-response stabilization. Big props react slower to throttle inputs, so this should improve the viable size range