enter image description here

I've been looking over some pictures of the drone above but I'm not sure if it uses a swash plate or not. I understand there are some freely hinged rotor concepts known to work at this scale but I'm not really sure about this one.

  • 1
    $\begingroup$ Based on slide 13 of this 2014 PowerPoint presentation, it looks like it does. $\endgroup$ Commented Jun 29, 2022 at 8:59
  • $\begingroup$ @sempaiscuba that's the best answer I've seen to this question, perhaps consider making an answer based on it and get some rep in the process ;) $\endgroup$
    – Jacob B
    Commented Jun 29, 2022 at 18:27

2 Answers 2


No. The Flir Black Hornet Nano UAV does not have a swashplate. The rotor blade pitch is controlled directly by servos at each blade root. The servos are held by a structure that rotates around the rotor mast. If you zoom in, this picture shows the two “button” servos clamped in the support structure. Drone side view

  • $\begingroup$ It doesn't look like there are any servos directly on the blade roots. Perhaps I'm missing something. Could you provide a link or source of where you found this information? $\endgroup$
    – Jacob B
    Commented Feb 10, 2022 at 23:19
  • $\begingroup$ @Jim what are those metallic beads near the servos for? $\endgroup$
    – Mridul
    Commented Feb 11, 2022 at 8:21
  • 2
    $\begingroup$ The metallic beads are most likely weights. Rotor blades need their centre of gravity to be quite far forward to reduce control loads and prevent flutter. This way, if a gust of wind causes the blade to flap up, the weight will pitch it back down. Larger helicopters can have blades that are hollow at the back. $\endgroup$ Commented Feb 11, 2022 at 9:17

Based on slide 13 of this 2014 PowerPoint presentation, it looks like the PD-100 Black Hornet does indeed incorporate a swash plate.

Image of slide 13

Now, a caveat here is that slide appears at the end of the section describing the development of the Hornet series of drones. It does not state explicitly that all the systems shown are present in the Hornet 4 / PD-100 Black Hornet.

However, comparing what we can see of the drive mechanisms in this video, for example at 40s:

Image of Black Hornet rotor

and the low-res images of earlier models in the Hornet series shown in slide 10 of the presentation cited above,

Hornet series of drones

they do all look to be closely related to the rotor assembly mechanism (European patent number EP 2 499 045 B1) patented in 2010 by Petter Muren, founder of Prox Dynamics. That rotor assembly includes a rotating swash plate.

Prox Dynamics was the company that developed the PD-100 Black Hornet. Prox Dynamics was subsequently acquired by FLIR Systems in 2016.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.