VTOL RC Airplane Tricopter COG, Liftoff Weight Calculations

[socalaerospace]

Hello,

I am interested in making an RC plane as illustrated. Some questions:

1. Given that the build material of the plane will be 3d printed out of PLA and I want the wingspan to be between 1.2m - 1.35m ideally. How can I calculate the minimum wingspan/wing shape/wing area to carry a payload of approximately 1.2kg?

I would estimate that the body of the aircraft will weigh about 800g - 1kg including motors and tilt rotor mechanisms.

2. How can I calculate the placement of the two motors in the front relative to the rear motor for yaw? It has to be for hover mode, and forward flight. (ie: distance between front two motors, distance between front two motors and rear motor based on center of gravity)

3. How can I calculate the ideal motor kv and size based on the above? Then once I choose the right motor, how can I calculate the flight time/distance/efficiency based on 12,000Mah?The purpose of the aircraft is for FPV, long range, and VTOL with a stable hover mode.

 

[jrmichler]

Your questions are too broad to answer here. You need a book on the subject.

I have a first edition copy of Aerodynamics, Aeronautics, and Flight Mechanics by McCormick. It has good coverage of conventional fixed wing aircraft. The second edition is available from Amazon: https://www.amazon.com/dp/8126523786/?tag=pfamazon01-20. The cover photo shows a tilt rotor aircraft. That book might meet your needs because it covers lift, drag, thrust, propellers, performance, and stability around all three axes. Searching aerodynamics on Amazon will find other books on the subject.

I bought this book back when I had the idea of designing and building my own airplane. I read the book and decided to do something else.

 

[berkeman]

https://www.amazon.com/dp/8126523786/?tag=pfamazon01-20

Nice!

 

[Lnewqban]

Welcome!
I recommend these books:
Model Aircraft Aerodynamics by Martin Simons

https://www.amazon.com/dp/1854862707/?tag=pfamazon01-20

Basics of RC Model Aircraft Design by Andy Lennon

https://www.amazon.com/dp/0911295402/?tag=pfamazon01-20

Learning to safely fly a rc aircraft takes some time.
Designing and building a model that can properly fly is not too difficult, unless you have zero experience doing it.
The tilting is the difficult part.

It takes a great deal of digital controls to make it work in full scale airplanes.
The machine must smoothly transition within a range which extremes are flying hanging on the blades (like a helicopter or drone) and flying hanging on the wings (like a glider or regular airplane), all while keeping a perfect balance.

You could also consult expert modelers in these sites:

https://www.rcuniverse.com/forum/

http://www.rcgroups.com/forums/index.php

Then, there are new regulations from the FAA for legally flying rc models in USA.

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