3Decipher F3P V2

[chris-b-chips]

Hey guys, thought I'd start a thread on my own design 3Decipher F3P bipeplane V2. (you can find the version 1 and plans here http://www.rcgroups.com/forums/showthread.php?t=628368)

specs:

-32" span
-170-200g weight (looking around exactly 200g so far)
-Axi 2204/54 motor
-Hyperion 3s VX300 cells (ordering them soon)
-9g servos
-Shultez reciever
-MGM copro speed controler (8amp)
- bare depron pieces weight 77g
- finished airframe (with carbon bracing, w/o electronics) 88g

Alot of ideas have come from the donuts models saturn so im hoping it will take some of the same flying qualities. I will eventually release plans for plane but probably not for a couple of weeks.

Changes from V1:

- lighter simpler construction
-longer tail moment arm
-slightly smaller size (32" down from 34")
-inboard struts (exactly like the 'Saturn')
-Pull pull on tail surfaces
-rudder drag plate

Here are some pics:



Chris B.

[Nooflyer]

How does it fly? It looks slow with all that wing area!

[chris-b-chips]

hasnt flown yet! lol, give it a week at the most!

[chris-b-chips]

Gave it a bit of colour! Not bad for built in one day! All I need now is some kite string to rig the pull pull system. Weight as it stands is 170g, thats everything minus pull pull string (2g?) and batteries (till deciding but around 29g) so thats pretty close to 200g. You can easily cut up to 20g off what it is at the moment, lighter servos (currently using 9g servos) lighter reciever (currently 9g) lighter speed controller ( currently 9g) minus undercarrige (5g) not to mention using it will be using a 3cell battery, so 2 cell could also cut the weight down. It will all add up pretty quickly!


Chris b.

[matchlessaero]

Very nice Chris.... I like the lines.... :)

I still think your horizontal is too small though ;)

[chris-b-chips]

LOL, thanks matchless! You do definately feel the smaller stab in a hover (in V1) but only a tiny bit. The pay off for good snaps is worth it i think, even though there dont seem to be many (if any) snaps in these F3P sequences. This one will get lots of flying (i hope) so I'll see if I will change it for the next one. But I do agree with you, the elevator does look a little wierd on the plane.

Chris B.

[matchlessaero]

BTW, I like the rudder brake... After the experiments I did with trailing edge brakes on the rudder, and found the effects of putting them on a trailing edge that was not perpindicular to the path of flight, I had thought about hanging them out in the wind much like you did.

I may have to give your aileron servo mounting location a try as well. Looks like a good place to mount it in order to keep the vertical balance right.

[chris-b-chips]

yep! Thats what I've found with all the bipes I've designed, the vertical CG is the most important. most of the time I end up mounting the battery on the top half of the fuse.
I cant take credit for the rudder brake position, that idea came from the 'Saturn', I just cut a big piece of scrap depron at a prefect right angle, and used it as a jig to align the brake perpendicular with the horizontal fuse.

[Dimitry999]

Why don't you put airbrakes on the wing?

[chris-b-chips]

There are some small ones on the outer struts if you look carefully, they're about 1" wide and go all the way from the bottom wing to the top wing.

[chris-b-chips]

Hey guys, quick question, what battery would you guys use (just your opinion) i have narrowed down my choices to:

-Hyperion VX300
-Polyquest 'Twenty' 300
-2 dog rc 460

All are 3s and i'm going to be using the axi 2204/54 and try and prop it for 8 amps.

Thanks,

Chris B.

[Aio_1]

Looks good Chris!

I do think Matchless is probably right about the tailplane.
One nice thing about depron planes is that it's easy to add and remove material to try things out. You can easily add some depron to the tailplane to try out a larger surface before building the next one. Just tape a strip of depron to the leading edge, trailing edge, tips or all three. You can trim it with a scalpel between flights 'til it flies the way you want it then tidy it up later. Remember that the CG will move as you add/remove material so you'll need to compensate. I'd just tape on a small coin and move it forward or back as required!

The Hyperion cells are excellent to 6A and should manage 9A burst but you'll be pushing them quite hard. 80W is a lot for a plane that size. I think if you prop for about 6A or 7A on 3s you'll have plenty power but the cells should manage if you want more power available for brief bursts. I think the Polyquest "twenty" cells are almost identical to the VX300s. I know very little about the dog rc 460.

Aidan

[chris-b-chips]

Thanks Aidan, thats exactly why I'm starting off with a small elavator (mind you its probably easier to take off material than to add) because its quite easy to add some more material.

Thanks for the info! I'll aim for 7A.

[Nooflyer]

What was the airframe only weight? I bet you can get the airframe lighter not just from the servos or receiver but the airframe! That way it'll just float like it's in space! I'm not an expert at all, My way of thinking is if i get my plane light enough it'll give me more airtime as in flight time (more practice) and it'll give me more time to think while I'm flying as far as learning new stuff! Great looking plane!

[chris-b-chips]

Absolutely! Im trying to get the weight down as much as possible, bare depron weight was 72g, final weight (everything except electronics and linkages, but including control horns and the link between the top and bottom aileron) was 86g.

[chris-b-chips]

Ok, finished the pull pull tonight, AUW without battery is 172g looking on target for 200g!

[Dimitry999]

When it flyes, put some pictures or video how it flyes.

[RooC]

Yes, put vid and planes! ;)

[chris-b-chips]

Well its flown, briefly, just to see what its going to be like, so far, SLOW and lots of rudder power, as you've come to expect from these models, point rolls using only ailerons. I will do some more testing once my new batteries and props get here so that i dont burn the motor out. No vid sorry guys, it was a spur of the moment type of thing, early morning at and IMAC comp before the wind picked up. Dont hold your breath for plans as I have to keep my priorities right with schoolwork and other things.

Thanks,

Chris B.

[RooC]

Well its flown, briefly, just to see what its going to be like, so far, SLOW and lots of rudder power, as you've come to expect from these models, point rolls using only ailerons. I will do some more testing once my new batteries and props get here so that i dont burn the motor out. No vid sorry guys, it was a spur of the moment type of thing, early morning at and IMAC comp before the wind picked up. Dont hold your breath for plans as I have to keep my priorities right with schoolwork and other things.

Thanks,

Chris B.

I like that! :) I'm looking for slow and stabile F3P/3D plane. Now I'm flying with Smove bip, but I want something new! Waiting planes!

[chris-b-chips]

Batteries and props arrived! should be able to do some flight testing tommorow. Soldered on the deans micro plugs and its good to go. Power feels awesome, plenty of pullout for a hover. I'm liking these Hyperion VX300 batteries, 3s only 27g (thats 2g under the advertised weight!) and the voltage barely drops under 6Ah load.