Titan Glider Fighter type trainer.

[Foam Addict]

Hey all,

I've noticed that there are few cool looking trainers on the market, and even fewer that you can scratchbuild. Therefore, when I encountered the Airhogs titan at Walmart in California, I turned it into a simple trainer that almost anyone could fly. A supercub stock motor with a 2 cell 1000MAh nanotech provided the power, and a mixed set of servos provided control.







This trainer had only one weakness: TEEPSTAHLLS! translation: tipstalls. The wing had Wash-in designed into it, and was nightmarish to land. It also spent 20 min. in a pond after the prop flew off! I gave this aircraft away to one of the Cadets, since I had been given 2 other aircraft during the week, and had tried to replicate it, but had been unsuccessful due to the stock wing's tipstalls.

So today at lunch I found the Titan Glider thread on RCgroups (http://www.rcgroups.com/forums/showthread.php?t=1206083), this thread had a wealth of information, including that the plane flew better if the larger wingtips were removed. And I just happened to have purchased a new Titan on summer clearance.

After about an hour, this slowly emerged from the garage:



The first flight was not great as my thrustline was WAY off, that, with insufficient Rudder and Elevator throw, doomed my launch, but thankfully, the titan is very durable, as I discovered later.

After adjusting the thrustline and trims, the titan flew great. The speed range is fantastic, with about 55 MPH being my top speed guess, and It looks really cool in the air. It is also very very docile, having only a sharp pitch down when power is applied instantly. A slow increase in throttle take care of that well.

As I was flying, a neighbor who is fascinated with RC models, but has not flown since his teens came to watch me fly. He and I were chatting while I flew, and soon I decided to let him fly for a while. He was able to fly the Titan for about 2 minutes without instruction or guidance except to tell him what a pattern was, which he promptly executed. This was excellent performance, but his flight came to an abrupt end when he applied power at low altitude and didn't compensate fast enough for the hard roll. Although the fuselage had snapped in half, within 3 minutes we were back in the air, and I coached him to his first landing.

This is a testimony to the excellent performance of this craft as a trainer, and to its modability. I will be posting a fighter type mod on my other airframe later, when I complete it...

 

[Craftydan]

Grrr . . . I'm 0 for 2 on Titan kitbashings . . .

I mean, That's awesome FA! Great cheap airframe, once you undid all of AH's design flaws!

. . . gotta drop by Walmart and see if I can make it 1 for 3 . . .

 

[Foam Addict]

They are on sale right now, the keys are 5-7 degrees left thrust and and 5-15 degrees up thrust as a pusher.
Don't worry, I'm technically 2 for 4, but I've tried twice on one airframe.

 

[knife-edge]

I've got one, and every time I pick it up I want to do something with it. I want to mount a motor on the back and have a little differential thrust instead of a rudder, but time will tell. A quick question, what are the pros and cons to washout? I want to keep the length of the wings and was thinking about just sanding out the washout.

 

[Craftydan]

You mean sanding out the wash-in. a washout has the tips at a lower angle of attack than the remainder of the wing, so when the wing stalls, it stalls at the root first, not the tips.

This seems to have escaped airhogs, since they put it on backwards. That means the wingtip will tend to stall first, so it likes to drop a wing . . . probably on turning approach to landing -- or should I say approach to crash?

Sand away my friend! Flat will put it back to tipstalls on slow turns (instead of in any stall), or keep going and it'll resist that and maybe drop the nose instead.

Oh, and stay away from that RC groups thread -- TOO many *cool* ideas. keep it simple and hopefully you'll have better luck than me

 

[Foam Addict]

It actually glides almost as well with the wings cut down, but if you want, you can just slice half of the tips off, and that works much better, as it eliminates the washed in portion of the wing. 2 motors you mean? Its been done in that thread, or one of the 5 threads I've found, But I don't know whether it worked or not.

 

[knife-edge]

Thanks guys. Craftydan sorry I should have said wash in. I think that im going to just sand the wash in away to have a flowing airfoil through the whole wing. I was also going to add flaperons between where rhe washin starts and the fuselage. Is this where you guys cut your ailerons? Also where is the cg as ive tried 1/3 of the cord and still feel like it isn't right. Thanks and Craftydan you warned me but I still got sucked into that rcgroups thread. There are some amazing scratch builders out there!

 

[Craftydan]

I was also going to add flaperons between where rhe washin starts and the fuselage. Is this where you guys cut your ailerons? Also where is the cg as ive tried 1/3 of the cord and still feel like it isn't right. Thanks and Craftydan you warned me but I still got sucked into that rcgroups thread. There are some amazing scratch builders out there!

*disclaimer* I haven't gotten this plane to fly well . . . yet.

Use a CG calculator. The stock Titain is frightfully tail heavy. In a chuck glider, porpoising looks cool. In a controlled craft, it's a nightmare!

I ran RET at first, and it was marginally controllable -- mostly due to bad CG. Added ailerons from root to half span and it didn't help much at all, but when the tail is trying to swing out from underneath, what do you expect?

Second attempt was the canard style, and had a bear of a time getting the canards alligned. Shold have scrapped and started over, but finished the buildout, and ripped a canard off on maiden. On that one, for ail, I went the full length along that back notch, to the depth of the notch. used stripped & taped DT foam with a fiberglass spar on the TE for the control surface. While the plane was *barely* flyable due to alignment, the elevons that size had enough ommph to fight the natural twist in the misalligned airframe.

Yeah, that thread is like sugared crack. Every time I go there I want to build one of those . . . debating on retrying the simple clipped wing RET . . . or maybe the funjet mod . . . . or maybe . . .

 

[Foam Addict]

Knife Edge: I would recommend that you buy 2, they are on sale right now.

Clip one set of wings, and leave the other for experimentation. Build your first Fuselage as a podded motor like mine, and get used to how it flies, next build a reinforced pusher jet version with the same CG and wings, then add Ailerons to your podded version wings. This will help you get used to some unique flight characteristics of a swept wing RET aircraft.

The H-stab is in desperate need of reinforcements, and can be blown right off the plane if you have more than 100 watts of power!

Mine can Rudder roll at speed, but is incapable of a loop, except out of a very steep dive. This is on only 60 watts of power lugging a 2200 3 cell around. Albeit at a 70 MPH pitch speed.

Good Luck, I hope that yours works great.

 

[knife-edge]

Thanks. Ill pick a few up. They're only $10 at target normally so im fine if I cant get them for less. A little reccomendation, at lowes or home depot you can buy laminated fiberglass rods (I think they are for mailbox supports or something like that) for like $1.50 a rod. They are super light and are probably stiffer than CF. Thanks for the help. Ill show off some pics when I get one to fly

 

[Foam Addict]

Speaking of getting one ready to fly...


I modded the plane for a Battery bay, It should be a bit lighter and faster now with the battery inside, I really need to do something about that nose!

I also have a Vtail jet version I'm working on.

 

[knife-edge]

Looks pretty sweet! Do you think that the rudder would be necessary if you had ailerons? I'm trying to keep the weight off of the back due to it being so tailheavy.

 

[Foam Addict]

No, In fact, I'm losing my battle to keep a good RET version, as they are to hard to launch and land. Go with ailerons, they work so much better. I built 2 more, and one hasn't flown successfully yet, and the other is drying out after landing in a lake which has formed from the foot of rain we've had. I told my mom that I need a seaplane!

 

[Foam Addict]

Well, the stores are gearing up for summer which means that the Titans are back!



This version is the best so far, it uses a Vtail for durability on landings, a rear mounted motor, and ailerons.
This one is easier to launch and doesn't suffer the violent pitching of the pylon motor designs.
The downside is that it has a 10x 1/2" steel nail in the nose for balance, not so floaty as I'd like.

Sorry for the looks, normally it's a good thing to run out of red tape.