Introduction to the Orange Hawk Project from Stephen Carlson on Vimeo.

Presented here is a VTOL aircraft design that I've perfected over 16 months, and intend to release as an Open Source project with design plans and code. Initial details:

Wing Span: 1000mm

Area: 21.5+2.6 dm^2 (Elevons)

Quarter-Chord Sweep: 30.0deg
Airfoil: MH45 with Root: +2.0deg Tip: -0.5deg

Material: 21.0kg/m^3 EPP

Equiv. Rotor Diameter: 500mm

Flight Controller Based on MultiWii 2.1

All-Up Weight: 1.2 kg, Theoretical Maximum: 1.5 kg

Designed Fall 2012

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  • Great work!

    I can't help but think this sort of thing (VTOL aircraft) is really what a lot of people want, rather than a pure copter or plane. They just haven't had a lot of (economical) chances to find it out yet though... With some natural lift, duration and motor-out options (incl. public safety) should be greatly improved, along with the other stuff people mentioned too.

    Very nice.

  • Thank you all for the kind remarks! A few questions answered:

    Tail motor is permanently attached at a 10 degree forward angle.

    I'm eager to share this, but need to be careful/methodical. I will share design plans and code contingent on two things:

    • Need to select which creative commons license is appropriate, and label all the design files as such. However, I think I can safely release the MultiWii Code as it is already under the GNU-GPL, and can be reposted freely, (correct?).
    • I will be presenting this project at the AIAA Region VI Student Conference in Salt Lake City on March 28th, 29th and/or 30th, and may need to keep most of the artwork until the formal public disclosure there. And, I need time to polish the artwork / build plans.

    Also, check out the work done by the guys at the RcGroups VTOL Forum: http://www.rcgroups.com/vtols-360/ . I would like to specifically recognize RCvertt and leadfeather there as the guys who inspired me. Also, check out Peter "foam and tape" 's aircraft. Also, check out the IAI Panther: https://www.youtube.com/watch?v=9DzqO1xBF7A
    I've looked at trying to cross the *Copter and *Plane code, but code size problems exist as noted by Gary McCray here: http://diydrones.com/photo/hybrid4b . I agree, and I simply have not had time to really sit down and make the attempt, even though I have an APM 1.0 and the skills to do so.

    Maxime Carrier
    I did a rear pusher motor configuration 6 months ago, a precursor to this project. Check out the video here: https://vimeo.com/50186677
    The concept suffered some controls and mechanism issues, and required a dive to enter forward flight. The front motors were fixed upright, and the back motor did both yaw and tilt on a 2-degree-of-freedom gimbal.

    Code provides two options: direct tilt control and 3-position mode, like APM mode select. In the test flight shown, I used the 3-position mode. The three positions: Up, 50/50 mix, and Forward. In the code, I made a sine approximation function for gain scheduling of the three motors, and I have it scale between the two mixing modes linearly. In forward flight, the front motors are fixed forward with no arm tilt mechanism setpoint control in either roll or pitch, but the yaw command is added differentially to the motor throttle setpoints. The rear motor is fully turned off with the propeller lightly windmilling in the flow. In hover, all the motors are mixed as tricopter arms with the yaw PID driving the tilt arms differentially to control reaction torque from the back motor.

    W. Joe Taylor
    Thanks! Hover and forward flight times are still yet to be measured, and I need a new set of lipos to really give that a good metric, as I'm using a wimpy 3s2200 25C at the moment.
    I am dreaming of doing full autonomy with this, even have the ground target defined as shown in this picture: http://diydrones.com/photo/orange-hawk-and-landing-pad . It would be awesome to use this at the SparkFun Autonomous Vehicle Competition, I'll have to see how my summer turns out in terms of internships and where I'll be.
    I remember Dr. Taylor, and I have not seen him for a least a year or two. I believe he has left, not sure where.

    Go to get to class and school work, but final notes:
    Shall we name the mix between the ArduCopter and ArduPlane codebases: ArduVTOL? ArduHybrid?

    What license should I choose for the design files? CC-BY-SA, CC-BY, CC-BY-SA-NC ? What are the Pros, Cons?

    Any suggestions for where to post/host the design files?


    VTOLs - RC Groups
    For Vertical Take Off and Landing aircraft.
  • Wow that is just awesome and really slick looking.

  • Moderator

    Fantastic, Congratulations on your achievements with this concept. It made my weekend to see it in action.

    I just have to fugure out how you did it. real cool and fun to watch.

  • Amazing work! Simply outstanding!

    You successfully created a perfect hover + high-speed aircraft in one. Props!

  • Super cool design and build. Looking forward to seeing the Orange Hawk evolution. Cheers!

  • Awesome Stephen!

    Saw a similar set-up in France about 7 years ago, but it was a quad.  How long is flight time in hover, and in forward flight?  The one in France did not use the MultiWii board.  Looks like those controllers have also come a long way; but, I was wondering, do you plan to make your VTOL be capable of autonomous flight, as in GPS way point Navigation? Self transitioning from VTOL to Forward Flight, then back and landing at start point? 

    Also, I was wondering if Dr. Clark Taylor is still at BYU, he had a great vision system for drones back in 2007 where we talked about it at the IROS Conference, San Diego.  With his system, the forward flight on a drone would track an object on the ground, circling it, even a man or car, going under obstructions.  Just wondering.

    Great Flight video too.

    Best of luck.


  • very nice! brings together the best of both worlds :) 

  • Maxime Carrier, initially I also thought same as you but later I realized that for a tri-motor config, he has to keep the rear motor, able to tilt in order to counter the anti-torque by front motors.

    So making the rear motor as pusher, after the flying wing is airborne, would require one more servo at the rear motor.

    There could be another configuration and that is to have two motors in the back as in front.

  • Very interesting! How do you make the translation from flying wing to tricopter?

    Can maybe someone convert apm 2.5 from arducopter to arduplane with only one switch?

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