RC Planes

Soldato
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That makes sense then, I was going the other way

Although I did try it with the wind in to my face. it shot up uncontrollably very high, looped over and came nose down I couldnt control it. Even with high throttle it didnt really do much, just went up, over, and came down on its nose.

So it turns out I was launcing in the wrong direction, however it was too windy to launch in to the wind that day, so it seems

I always thought that was against the wind, seems I was wrong lol
 
Associate
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Wind direction is really important. Remember ground speed means nothing to a wing, it's only about the speed of the air going over it. If a plane stalls at 5mph, and you've got 10mph wind from your back, you've got to throw it at 15mph for it to fly. If you throw into the wind you'll only need to throw at 5mph to see the same effect. If it's dropping down on launch it might just be that it's not getting enough lift to keep it flying.

Try launching facing the wind, if it still drops, just move the battery a small amount rearward.

Electric? wow, how much flight time?
About 9-10 minutes. It peaked at pulling about 180A on full power holding about 46V, but average in flight current was only about 60A, which is still 2500-2800W or so, nearly as much as a kettle ;)
 
Soldato
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Yeh got the wind direction wrong, makes sense now, although I think it was too windy to fly that day

Cool, sounds good :) how comes you didnt go nitro or petrol for extended flying times, or did you want a pure electric model?
 
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I used to work for one of the biggest players in the battery market, a lot of the electrics was sponsored as I competed and displayed around EU and once in the US too. It was a show-piece, totally impractical for it's time (2008-2009), but it was a fun aircraft. This size electric is a little more practical now as batteries are cheaper, but the charging is still an issue, you've really got to have a generator setup at the airfield to keep it topped up. It was heavy too, it wasn't wonderful to fly but it was a beautiful aircraft, especially once I had it all polished and waxed (it was composite) it really shone in the sun.

The second one down (Sebart 2.6m Sukhoi 29) was petrol, using an 85cc petrol engine. Went for a super light weight setup for that with lower power, but it was a total animal to fly, just amazing fun. I've got one video of me mucking about after a the first day of a competition I was in, including a crash. https://www.youtube.com/watch?v=r5w0iZ-aXwo Got it fixed up and won the next day so no complaints :)

I flew only nitro (or glow as it used to be called) until about 2007 when Lithium batteries became powerful enough to be used, then I switched all electric. I then got the petrol Sukhoi and also the yellow helicopter in an above picture, an Avant Aurora, which was nitro, used to drink nearly a litre of 30% nitro fuel in 7 minutes :(
 
Soldato
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18 Oct 2002
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Sheffield, UK
You need to come back to RC.

I can't speak for planes, but helis have moved on MASSIVELY. I started flying in 2009, and it's already a different world.

Tiny little 3D capable micros you can fly in the garden, to massive 10,000W (13 horsepower) 700 size electric helis. Both were impossible back then.

Unfortunately 90 class helis still drink fuel like it's going out of style, but now it's usually a 105 or 120 engine.
 
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I bet, heli's were coming on leaps and bounds. My Logo 600 was a machine, V-Bar, peaks of 4.5KW I think, loved flying it. Binned it so many times it was painful, but all part of the fun.

My tastes have changed now, I'd rather like a jet or a nice scale twin. Also, I'd love to get another DLG glider, they are ace!

Still, new PC, then I'll think about it. I've got a lot of catching up to do first on the new tech on the market!
 
Soldato
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Both my AXN Floater Jet and DJMK4's Bixler I believe suffer from the same thing at launch, because the engine is on a pod/nacelle above the rear of the wing it leads to the plane pitching down under full throttle (and noticeably up when you drop/cut the throttle as well), hence the switch for 'launch mode'.

I was with a friend so he was launching whilst I had both hands on the controls, max throttle, launch mode stick on and it worked pretty well.

The max trim up on the elevator does put it into a slightly up position on the tailplane, but not by much, it does seem to lack travel on the up elevator which I want to tweak but may involve cutting off the elevator and putting it back on with a tape hinge.

CoG was correct I believe, just at the front of the main wing spar, which is conveniently just one of my batteries pushed as far into the nose as possible.

With the very small amount of constant up elevator to counteract the motor it was flying fairly nicely, in my n00b opinion at least :)
 
Soldato
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Yeh I heard about that too. It can be OK though. Just have to get the right launch attributes


I'm going to buy a new carbon rod for the wing as my broke.

Trying to find some m2 14mm self tappin screws as the new control horns I have from hobbyking don't come with them and they don't sell m2 there.

Was looking at these

http://www.ebay.co.uk/itm/M2-2mm-di...t=LH_DefaultDomain_3&var=&hash=item257ba37c84

Although I may glue them on and stick cocktail sticks through the holes.

Its only my elevator one I need to replace
 
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I didn't know the aircraft in question but the thrustline being above the CG would make sense. Depending on your radio gear, you can do a throttle to elevator mix to get the worst of this taken out. Or, launch at low power, pitch up then add power to avoid it stalling and climb away

It happens on all aircraft without central thrust lines, no matter the size. Try flying a Boeing 737, you need a heck of a lot of arm strength to keep her from pitching up at low speed/high thrust.
 
Soldato
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Yeah I did see the option to mix throttle/elevator (although knowing the stock 9x firmware it's probably broken in some way :p) and it may help but it didn't seem too bad.

For the launch I was using 100% throttle, the elevator/launch switch and my mate giving a decent throw at around 20 degrees or so, that seemed to work nicely (probably mostly the launch switch overriding the 100% throttle).

During flight I didn't notice much on increasing throttle but after turning downwind and needing to throttle back I did get the nose pitching up noticeably a few times, essentially when just shutting the throttle rather than slowly decreasing it, not enough to stall but enough to need a good bit of correction.

I think the benefits outweigh the awkwardness though, my mate started a bit ago with a Flite Test Spitfire, he's gone through several props already, I can't see me breaking many props with it high up, especially as by the time you touch down the throttle is at 0% anyway due to the plane gliding quite well.
 
Soldato
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Nearly sorted :) got a new carbon rod for wing, just need to glue another rod on the inside of the tube. Then sort out the Velcro to hold the wing joins and put another elevator control horn on. And sort out the aileron as that wasnt working for some reason on my rate switch

Working on most of it tomorrow

Are you still coming out with your model?
 
Soldato
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I went out nice and early this morning to get some more flying in, 3 batteries and 3 successful flights \o/

Had a play with the elevator last time and tweaked it so it doesn't rely on the trim anymore and that was fine.

Also first time hand launching myself which was interesting but overall not too bad, on the second launch I forgot to use the launch mode switch but just saved it as it was skimming the grass so all good :p

I was half planning to do a loop on the last battery but I chickened out :(

I also think I can increase my flight time, I've got a timer set to 7 minutes and my battery voltages were 11.9, 12.13 and 12.07 with the 11.9 being the first flight where I forgot to start the timer for 'a bit', but not sure how much I can add whilst still being safe with the lipos...
 
Soldato
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And just got back from another 3 batteries, upped the timer to 10 minutes and got 11.8-11.9v, done some reading and ~11.2v minimum seems fine so potentially could up the timer, or just leave the slack for as I get more confident and use more throttle.

Again went pretty well, fair bit windier than earlier which does upset the plane a bit but it handles ok, worst bit is it occasionally just refuses to turn when turning up wind, full ailerons and it's just flat, but speeding up seems to help and/or waiting.

Did have one moment, was flying low-ish, went overheard and as I turned I realised there was a massive tree just there, pulled up and throttle and I cleared it but it must've been close.

And then for the last landing I aimed to get it a bit closer to me than previously, except I ended up having it coming right for me, and rather than abort or move myself I went to turn, with ailerons, wing clipped the grass and it did half a somersault into me, first crash! no damage though so all good :)
 
Soldato
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Are you still coming out with your model?
Yup :)

F14 is nearly finished!





Flanker is going to be a while, it's so damn fiddly :(
Might make (start) a profile 3D fixed wing or maybe another Ultron this week to.

Gonna start the glider this week when I can find a large enough flat surface to build the wings on.
 
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Soldato
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I've always thought about getting a plane, are they hard to fly? I've got helicopters. Trex 450 for safe flying and a Copter X for trying upside stuff and it's pretty hard but planes scare me as you can't just spin around and fly back! We have a RC air strip so to speak near us so perfect place to fly!

I have a DX6i with spare receiver so would only need a plane and electrics to be flying.
 
Soldato
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Looking good :) can't wait to see the f14

Sounds like you have your hands full at the moment :) I should have my bix ready in the week.
Yeah. Luckily I have no kids :D AWesome looking forward to seeing that fly!

are they hard to fly?
It's a little like flying heli's/multi rotors in as much as the controls will be reversed when upside down or front on to the plane.
Best thing is probably to find someone close to you to help or to buddy up with (they fly with one controller and pass over control to you and can take back control is things get hairy :D) or get an EPP model which is pretty much indestructable.

I started on slope soarers (gliders) under my old mans watch but I was lucky in picking it up very quick.

Do you have a copy of Pheonix RC?
 
Soldato
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It's a little like flying heli's/multi rotors in as much as the controls will be reversed when upside down or front on to the plane.
Best thing is probably to find someone close to you to help or to buddy up with (they fly with one controller and pass over control to you and can take back control is things get hairy :D) or get an EPP model which is pretty much indestructable.

I started on slope soarers (gliders) under my old mans watch but I was lucky in picking it up very quick.

Do you have a copy of Pheonix RC?

I do indeed. Awesome program. I suck at planes on it, they just fly away and never come back :(

Yeah i could use the trainer thing my controller has!
 
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