Some questions about VTOL.

Ocktiy

New member
Hello guys. I'm ocktiy, a RC vehicles enthusiast. I want to start building my first DIY airplane/drone/vtol. My requirements are: max wingspan 35-40 cm, total weight- about 300g, 4 engines(I want to be able to use it as a quad and as a plane). I'd like to use the N50 brushed motors. The design I came out with is a biplane with the motors mounted on the wingtips. My questions are: is my build possible?; what props should i use?; should I use gearing between motors and props?;do you have any better design ideas?. Also, please send me any tips you have for me. Thanks.
P.S.: sorry for my mistakes, english is not my language.
 

JimCR120

Got Lobstah?
Site Moderator
Hello Ocktiy.

I definitely think your idea is possible. Here are a couple of planes that already fly vtol. Maybe they will give you ideas for your design.

You have nothing to worry about with your ability to speak english. Which language is your native tongue? We are a worldwide community so there is a decent probability that there are others from your area as well.

Have you built any aircraft in the past? How long have you been in the hobby?

Welcome to the forum.
—Jim
 

PsyBorg

Wake up! Time to fly!
Welcome to Flite test mate.

As this IS Flite Test anything is possible here. Question is by what parameters is it possible. We can range from elegant builds that fly like a dream to a cinder block strapped to foam and being drug thru the air with shear power.

Bi planes seem to be pretty forgiving and very floaty so getting one in the air with 4 motors out on the wings should be a non issue. Getting it into a stable VTOL Hover for accurate take off and landing may be the challenge. Or not.... Many ways to start working around the issue.

If you are a math based person there are formulas and charts and tables and.. and... and...Maths. If you are hands on there is always the fun and some times dramatic trial and error. (we prefer this in video form to power the forums with so get many please) But there are also many that have walked the path before you where information and direction can be gained before even starting. Hope Goggle Fu skills run deep in your clan and are up to the task.

Anyway many smart people here to draw from so ask away on any specific questions that may arise in your endeavors to complete your project. Good luck mate.
 

Ocktiy

New member
Thanks for all your advices. I'm from Romania. This is the first aircraft I'm planning to build. In the past I've built only simple RC cars, so I'm not very experienced. I hope that this build will fly.
 

makattack

Winter is coming
Moderator
Mentor
Hello Ocktiy, and welcome to the FT forums! If you were looking at a DIY quad/plane VTOL, you might find the PX4 software pretty much already implements what you describe as one of its VTOL configurations:

https://docs.px4.io/en/frames_vtol/

The problem with PX4 is that the Pixhawk flight controllers are a little pricey and maybe too big for your specifications.
 
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JimCR120

Got Lobstah?
Site Moderator
PX4?! Cool. I've got one for EDC. Shoots nice. 18 rounds before reloading. Maybe you meant something else, Dave.

Romania! Excellent. I've met some Romanians back when I used to travel more. Buona diminatsa (I think). This will be your 1st DIY. What have you flown previously?
 

makattack

Winter is coming
Moderator
Mentor
Haha, Jim. Not to go completely off the rails, but there's a certain proximity to my shots out. PX4 software vs Italian PX4 hardware. Romania and Italy being in the EU. I'm now a terrible shot, so my "close enough to get on the paper" ideal is holding up.

To the OP, in reading your specs, I just saw the N50 brushed motors mentioned. Ah, you're looking to build a tiny little VTOL. I think that pretty much rules out the Pixhawk platform. Those FC's are much bigger than you would want. I do know there are lot of the betaflight (I'll adopt CraftyDan's *flight convention) controllers out there made specifically for brushed applications, so you might want to look at iNAV (the fixed wing fork of betaflight) for inspiration.