Tailsitter VTOL¶

A Tailsitter VTOL takes off and lands on its tail, but flips into the fixed-wing orientation for normal flight. The tailsitter rotors are permanently fixed in position for forward flight.

Tailsitters are typically mechanically less complex than other types of VTOL, and hence may be less expensive to build and maintain. However they are aerodynamically more complex, and can be harder to tune and fly for hover and transition, particularly in windy conditions.

Tailsitter Airframes¶

VTOL Duo Tailsitter

Two rotor VTOL that uses elevons to flip from hover into fixed-wing flight.

wingtraone

Forward flight more efficient
Hover harder to fly, particularly in wind
Hover and transition harder to tune
More compact form factor

VTOL Tailsitter

VTOL with optional elevons. Uses rotors to transition between modes (along with elevons if present).

Hover mode easier to fly and more stable
Less compact form factor (harder to transport)
"X" and "+" rotor configurations are supported (see Airframe Reference)

Duo Tailsitters are generally more efficient in cruise flight (4 smaller propellers are less efficient than 2 larger ones) and physically more compact. However as they are aerodynamically much more complex in hover mode, they are much harder to tune for both hover and transition. Quad tailsitters are easier to fly in hover mode, and more stable in windy conditions. Both are supported using the same aiframe type in PX4.

Setup/Flying¶

VTOL setup and flying are covered in the VTOL parent topic.

::: info The instructions are essentially the same for all VTOL. The main frame-specific differences are the motor wiring, and some aspects of tuning the configuration. :::