Hi,

I wanted to see what the interest would be on this particular build/model. This was originally designed by Maybz to be both a pusher prop or edf. unfortunately the edf version of this model was INCREDIBLY unstable and no one could really get it to fly right, at least from what I could gather from the forums (i.e. rcgroups).

Anyway with a lot of trial and error and a lot of modification, I did manage to get a working/flying test mule using...

2x55mm EDF
2x 4300KV motors
2x 30amp ESC
1x 2200 3S 25C battery
4x 8gm servos

I did have to stretch the wingspan to 28" (from 26"), move the CG forward and enlarge the vertical stabs by 20%. This setup gives 32oz static thrust on a model that weighs about 27-30oz. Attached files

 

Here are some build pix:

Attached files

 

Here is the completed model.

Attached files

 

I couldn't get a decent hold on the model to hand-launch it so I added a hook and created a catapult to bungee launch the thing.

Attached files

 

Here is the maiden voyage. All the stars aligned, the heavens smiled and I got the CG correct. Only now do I realize how touchy the CG is on this plane. The plane has to balance directly over the intakes. It really wants the CG far forward, if its only a little behind the intakes it is tail heavy and extremely unstable.

 

Very nice build!!!


How do you trigger the catapult? I have a couple of planes that are hard to throw and that would help a great deal.

 

Looks good! I agree with TT that you may need to move your battery forward a tad...looks a bit tail heavy.

I built one but modified it for prop.....it flew pretty good at speed but as soon as I backed off it got a mind of its own. I figured it needed more vertical surface aft of the CG. http://www.rcgroups.com/forums/member.php?u=35483

 

I got the idea from RCGroups, here is the link:
http://www.rcgroups.com/forums/showthread.php?t=33639&highlight=launcher+PVC
The designs show a foot lever to trigger the catapult.

You guyz are correct it needs to have the CG moved more forward and I already have the battery as far forward as it can go in the model. So either a bigger battery or some ballast in the nose.

 

I modified the plane to have thrust vectoring.

 

very nice - the YF-23 was my favorite of the ATF designs.

 

cool plane vicentel was watching the thrust vetoring video and you had your alrons going up with the tail wouldnt it be better for them to go down and lift the wing up will the tail is pushing down?

 

I'm not sure what you are talking about, almostthere, but he has it right. The left TV is synched with the left aileron and the right with the right.

 

Thanks, and yes I have tried it with the thrust vectoring and it was awesome, worked better than I hoped and right off the bat Then when I tried to get some video of it, the batter clip fails on me :girl_cray2: What's that about, it never fails :questions: Anyway, enjoy the crash at my expense.

 

That's a hard thing to watch :girl_cray2: :girl_cray2: :girl_cray2: :girl_cray2: :girl_cray2:
I hate seeing such a fine aircraft as that get crunched

GHB.

 

The battery clip where? On the transmitter???

 

Post-crash inspection I noticed the deans connector did not have one of its clips and if you move it slightly it would loose its connection to the ESC/BEC.

 

Not sure what you are getting at "almostthere". Are you thinking of using the ailerons as canards or flaps? If canards ,then the ailerons are not far forward enough, I believe they have to be forward of the CG. If flaps then, the ailerons need to be close to the CG in order for them to lift the aircraft instead of rotating the aircraft. The actual yf-23 really does have its CG way, way, way in the back and it is extremely gyro stabilized so it can get away with traditional flaps. My model yf-23 has its CG more forward so I'm basically using the aileron/v-tail control surfaces like a delta wing plane (elevon or delta wing mixing).

Thanks,
Vic

 

I was just notice when you gave up evelvator the aileron went up witch would make the wing go down witch is good for high alpha but if you trying to get more it work with the elevator for sharper angles if it went down it would lift the wing. i had it on one of my planes but it may be differnt on that one.

 

ok just went though maybz build log and see the ailerons and elevator are on the same servo so you cant change it for diffent flight modes.