Hello everybody, down below is my design of what I am calling the Falcon 64 because it is based off the falcon jet design and I will be using a 64mm edf fan to power it. I used Google sketchup which is a decent 3d modeling program nothing like autocad but it is free so can't complain there. I am kind of a newbie when it comes to scratch builds, I have only built flat foamies with no airfoil (except KF airfoils but those do not count). So I have a couple of questions that might help me have a more successful designing/building stage.

Ribs?
-The plane has a 36in wingspan and I have the ribs setup with 3 inches of space between them. Is that too much? Should i have more ribs in my wing?

-I was planing on cutting the ribs out of 1/16 balsa. Should I move up in size and use 1/8?

Design?
-What do you think of it? Would yo change anything?
-As of now I do not have a rudder. Would it be worth it to add them in?
-Control surfaces. Are they the right size?

I know it is a lot of questions but would rather have them answered now while the plane is still in the designing stage than when it is already put together.

Thanks in advance

Wicked look's good

Yeah things my favorite jet design of all time!

Originally Posted by j3tman

Ribs?
-The plane has a 36in wingspan and I have the ribs setup with 3 inches of space between them. Is that too much? Should i have more ribs in my wing?

-I was planing on cutting the ribs out of 1/16 balsa. Should I move up in size and use 1/8?

3" rib spacing is normal.

1/16" balsa is fine for the ribs.

Originally Posted by DanSavage

3" rib spacing is normal.

1/16" balsa is fine for the ribs.

Thank you! I think it looks pretty proportional if you ask me and will hopefully keep the weight down.

I will soon be ordering the carbon rods, strips, foam, and making a trip to the hobby store to get all the balsa. Then I will be able to start cutting out all of the pieces and putting this plane together. I do imagine that I will probably take me awhile to fully build the plane due to school and sports but atleast it will get my mind off those things

Once the build starts I will be posting lots of pics and maybe some videos of my progress.

Last thing, this is going to just be the prototype. If it fly's then great but if it doesnt then no sweat and back to the drawing board.

if you want a rudder(s), you can control one side only with a single servo and then use a torque tube between rudders to drive the other side. imagine the ailerons on a biplane to give you an idea. two servos on the tail is better and lighter than three servos.

Rich

Originally Posted by LuvEvolution7

if you want a rudder(s), you can control one side only with a single servo and then use a torque tube between rudders to drive the other side. imagine the ailerons on a biplane to give you an idea. two servos on the tail is better and lighter than three servos.

Rich

I was thinking about doing something along those lines so I dont have to have two servos controlling the rudder. Do you think the the tube/rod connecting the rudders would ruin any of the thrust output?

if you keep the rod close to the elevator surface, I think you'll be ok. or perhaps somehow have the rod above the elevator surface. I wouldn't worry about it too much. the only problem I could see you having, is if the rod material isn't very strong and flexes under load from flight stresses and/or efflux pressure. I'de use CF rod, Aluminum or both. another option to consider is rod shape. a teardrop shape is going to be much better than a round shape. blunt edge facing forwards.

Rich

You are the master at this stuff. I will look into all of those suggestions.

I would look at your final weight/thrust. You might have to move up to a 70 EDF to power it.
Make sure you strengthen the tail end for mine ended up fluttering due to the combine EDF flow and forward speed.
Did not install rudders and it flies well in gusty winds. This came about by playing with the CG.

for the rudder I would put the rudder servo in the center of the wing/fuse and then just run a flexible pushrod out the fuselage to each boom and then down the center of the boom and have it pop out the sides before the rudder LE and connect to the rudder via a conventional control arm. simple and slop free

Good lookin' design.

Here's my 2‬¢.
The LE on the airfoil is way too sharp. Will make for a twitchy elevator.

I would put two servos on the elev, one on each side. No elev twisting with that set up.
And a servo on each rudder.

The two extra servos weigh less than an ounce together. I would bet all the extra push rods and would be the same weight.

Well I've started the build!!!!

Check it out:

Also I would you y'all you keep this in mind, this is only my prototype and using this build as a experiment on how i would like to build future planes.

Built the vertical stabs and also started on the ribs for the main wing.

Starting to take shape.


It would be nice if you put captions on the photos! Nice to know what each is.