What do the vortex generators do for the FT-3D?

[synjin]

I’ve been thinking of making a 3D plane for a while and was going to go with one of the flat ones, but I saw someone on the put one of these together. After looking at the Bix’s build video I thought it would be pretty quick and easy. There weren’t any vortex generators in the original videos. What do the vortex generators do for the FT-3D?

Also, do 3D planes work better with lower kV motors? The plans say 810kV minimum, so I didn’t know whether that meant 3D planes liked low kV motors with bigger props. I was thinking a 2212, 1400kV motor with an 8” prop. I’ll probably run a 4S battery.

 

[Ketchup]

Usually for a 3d plane you would want a lower kv and bigger prop since that would give you higher thrust at lower speeds. In 3d that's what you want since you probably won't be going too fast and you will want the thrust to get a higher thrust to weight. The big prop will also help you get more prop wash over the tail and as much of the ailerons as possible.
As for the vortex generators, they can delay airflow separation from the wing and therefore reduce stall speed. To my knowledge, the vortices produced act like laminar flow while also adhering to the surface of the wing a bit better, so they should allow you to reach a higher AoA before the stall occurs.
This video by Samm Sheperd is so far one of the best I've found on VG's

Sadly he has passed away, but his YouTube channel is still one of the best sources of aeronautics related educational content that I have found so far. The more my designs progress, the more I find myself using the information in his videos. Soon I will be working on the biggest and most complex plane I have ever built, and some of the core techniques used for it come straight from his content.

 

[L Edge]

I’ve been thinking of making a 3D plane for a while and was going to go with one of the flat ones, but I saw someone on the put one of these together. After looking at the Bix’s build video I thought it would be pretty quick and easy. There weren’t any vortex generators in the original videos. What do the vortex generators do for the FT-3D?

Also, do 3D planes work better with lower kV motors? The plans say 810kV minimum, so I didn’t know whether that meant 3D planes liked low kV motors with bigger props. I was thinking a 2212, 1400kV motor with an 8” prop. I’ll probably run a 4S battery.

For any 3D plane, you want to build light. Doing a flat one is the best. Also the electronics should be light as possible and doing 2s or 3s with prop size in the order of 9 to 10 " range(SF) with a pitch between 3 to 4. Use one servo(center of fuse) for ailerons to save weight.

Leave off vortex generators, just adds additional weight.

Concept is to have plenty of power(to get out of hover) but you want to slow fly it for nice even movement for 3D stuff. Also, make sure there is plenty of airflow across ailerons, elevator, and the rudder especially when trying to hover.

 

[PsyBorg]

In the case of the FT3d the VG's were added to stabilize it in high alpha and hover. without them the pro pilot was struggling with wing rock and the ability to hold a good angle. Other things like flexing control rods were addressed as well. If you cant get the deflection or your surfaces flutter about they don't want to behave to well.

 

[synjin]

Okay, so I’m going to give the FT-3D a go. Maybe those 2212 930kV(?) motors and 10x4.5 props will actually be useful.

I still need an indoor plane. I’ve got some 2205 1500kV motors and a few sheets of 6mm Depron. Would this work for a 3D indoor plane? There are still four months of winter, and I have access to a large indoor space.

 

[PsyBorg]

Okay, so I’m going to give the FT-3D a go. Maybe those 2212 930kV(?) motors and 10x4.5 props will actually be useful.

I still need an indoor plane. I’ve got some 2205 1500kV motors and a few sheets of 6mm Depron. Would this work for a 3D indoor plane? There are still four months of winter, and I have access to a large indoor space.

Look into some of the profile planes. Super light and super agile. I'm sure you could easily do a knock off of anyone of them in DTFB and just copy the power train with your favorite brand of gear.

 

[L Edge]

If your going to try 3D inside and have some experience, suggest you look at EPP planes. To do any 3D stuff in a confined area, you need to be able to fly inverted and do knife edges so that you can recover rather than ending up trashing your plane. WHY? You don't have 3 crash heights to recover. Another way is to add a gyro and use head holding mode to help you learn, especially doing hovers.

Twisted Hobbies has nice 3D equipment and planes, but it will cost to get into. I fly in a dome and when someone comes inside, the plane is so light, the air pressure difference actually jars the plane flight path. Good company to purchase equipment..

Remembered, @Pieliker96 has a 3D plane and plans(excellent builder) so you might ask him if his would fly indoors.

 

[synjin]

Almost done with the FT-3D. (Pictured next to my father-inlaw’s first build, a Tiny Trainer.) We’ll see if the 2212 works. If not, I’ll put in a 2217.

 

[OliverW]

Look into some of the profile planes. Super light and super agile. I'm sure you could easily do a knock off of anyone of them in DTFB and just copy the power train with your favorite brand of gear.

Wish it was just that easy. Dtfb just doesn't perform for profile planes. EPP is the way to go

 

[synjin]

Well, I’ve been holding onto a couple of sheets of depron, so if I find I like 3D it may become one.