Heavy Lift Drone deHavilland DHC-2

Hello Sketchup folks. I’m working on my design for a heavy lift drone. I created some YouTubes where I describe the drone and show the math that (I think) demonstrates that the drone is feasible. I thought it is a good idea to let the heavy lift drone use an aircraft that already exists. I think there are many advantages to adding this type of a heavy lift drone. Advantages include: the aircraft already exist, so no need to design and fabricate a completely new item, the aircraft can fly using their wings in a fixed wing flying mode which is a safety advantage in the event the drone related flying activities progress into a failure mode. I created a Sketchup version of the deHavilland DHC-2 aircraft, it would be a truly heavy lift drone, I also created a version of the Cessna 172. The Cessna is smaller and lighter and needs less power and equipment in order to get it to fly in a pure VTOL manner. I created a YouTube video to give a brief discussion of all this. A real functional heavy lift drone needs a lot of parts and systems to let it actually fly up in the air and fly away. I am planning to make a set of short YouTubes where I discuss all these different parts. I have the Sketchup *.skp files for all these parts and if anyone wants to download one of these files, just let me know. Here’s the YouTube url:

Of note, the science states that humans cannot “fly” a drone for a number of reasons mostly related to the complexity of the calculations that are required and the speed with which these calculations must be made and then updated. Thus the controls of the drone are more a way for a person to tell the CPU of the drone what the person would like the drone to do. I am intrigued about how this control panel would look. My next step is to create my version of this control panel. Enjoy! Dr. Gray


Very cool! Have you seen this video from Daniel at rctestflight?

Can a Wing Increase Quadcopter Efficiency?

@Saul Thanks Saul for your interest. The efficiency of fixed wing flying to provide lift as compared to propeller based lift is very substantial. For heavy lift drones, I think they will all eventually be configured to use fixed wing flying. The 3000lb drone I discuss needs 800hp to rise straight up using propeller based lift. It only requires 90hp to give it enough sustained airspeed that appropriately sized fixed wings will give it lift equal to its weight. With a 600lb fuel load, it can fly about 30miles with propeller based lift and it can fly 490 miles with fixed wing based lift. pg

Is your design a tilt-rotor or are they fixed in place like the drone in the rctestflight videos?

@Saul Hello Saul, I want to design a true heavy lift drone, payloads in the 500-800lb range. This winds up with a drone that weighs on takeoff about 5000lbs. The wing for this weight application is complex and large, so tilting the wing is a significant mechanical challenge. Thus I chose only to tilt the rotors, other than the motor driving the rotors has the strength to also be their connection device, so I am actually designing to tilt the motors, but tilting the motors will also tilt the rotors. pg

Hello. I’m curious to know if you watched the rctestflight video.

@Saul Well I just watched it. Payload = 35lbs. That might impress the camera people, but military, rescue, transport, firefighting just are not looking to move 35lbs around. We need to look at 350lbs, 500lbs, 900lbs, and flight times of 6-7 hours. His wing action didn’t work because his drone is not optimized for fixed wing flying. Essentially vertical thrust propellers working to create horizontal flight by adding a little tilt to the drone have poor propeller efficiency at creating and powering horizontal flight. Thus the need either for dedicated horizontal thrust propellers or tilt rotor. And wing efficiency is directly related to wing airfoil and wingspan. What he really demonstrated is: on the topic of truly heavy lift drones, 35lbs payload is way too small, inefficient use of propellers to create horizontal flight results in inefficient results, choosing a wing not optimized for lift vs drag efficiency results in a wing that is not very efficient. I am not criticizing him, he just was using the tools of drone flying (lift from propellers) to try to solve the issues of fixed wing flying (lift from wing airfoils and airspeed) and those two aeronautical disciplines are so different that proper action in one discipline is not going to be very helpful in the other discipline. Thanks again for your interest. Dr. Gray