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Old Aug 29, 2012, 05:37 PM
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You've done it again!
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Old Aug 30, 2012, 10:55 PM
Flying FPV from the lab.
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Canada, AB, Lethbridge
Joined Jun 2008
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Lol, the fireworks was the most fun I've had for a long time. Old school kx131 performed like a champ in the dark.
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Old Aug 31, 2012, 01:30 AM
skidding in the sky
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Cheeky Arron, very cheeky

Have been having similar thoughts....
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Old Sep 09, 2012, 10:00 AM
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Hi everyone,

I'm not new in the work of skyfun flyers, but I am in the world of skyfun FPV flyers. And by the 32 pages I've just read, we do have experienced FPV flyers here

So basically here is my setup:
* skyfun with several epoxy drops
* vx/tx 1.2GHz - I think 700mW. 4 Channels. I've bought it on leBonCoin (equiv eBay) and the seller could not give me the model type.
* Turnigy T2836-2350 w/ 6x4 prop TGS Sport
* 80Amp ESC
* 3S 2200 mAH for the motor
* 3x600mAh in parallel for the Video part
* FatShark googles
* Remzibi OSD

Alltogether, I have approx 1070 grams fully loaded. Do you think it will fly / land correctly? I have not seen a lot of weight of FPV skyfun, so before I try (and crash it at landing), I wanted to have some piece of advice:
* motor configuration OK?
* can the skyfun handle 1070 grams? Will it not be too heavy at landing?

Thanks for the help!
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Last edited by rcfr; Sep 09, 2012 at 10:41 AM.
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Old Sep 09, 2012, 04:24 PM
Flying FPV from the lab.
aaron_gx's Avatar
Canada, AB, Lethbridge
Joined Jun 2008
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Mid-Air Collisions (2 min 49 sec)
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Old Sep 09, 2012, 08:35 PM
skidding in the sky
WitnessOnly's Avatar
Australia, VIC, Melbourne
Joined Jan 2010
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Quote:
Originally Posted by rcfr View Post

Alltogether, I have approx 1070 grams fully loaded. Do you think it will fly / land correctly? I have not seen a lot of weight of FPV skyfun, so before I try (and crash it at landing), I wanted to have some piece of advice:
* motor configuration OK?
* can the skyfun handle 1070 grams? Will it not be too heavy at landing?

Thanks for the help!

1 kg is fine, had mine up to 1.3-4kg (3000mah3S). Full throttle and throw, a bit of up trim to get you going and you'll be fine

The SF is a harrier landing monster (looks like the Space shuttle in some ways when its a bit porky), I cut throttle out about 50m or so and glide in to land as standard, lands well fast or slow.

It's a very underrated FPV platform in my opinion, you going to just luv it

Awaiting vid's
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Old Sep 10, 2012, 02:13 PM
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No vid tonight.... I had a first try without any load, but with the 6x4 prop to test it out before I try to load it... Bad launch: too much torque when full throttle made the plane turn left - I could not react in time, and landed a bit hard. Not too bad, but enough to break a bit the foam at the rear of the plane next to the motor mount.

Epoxied tonight, will try again tomorrow, with correction to the right at take off...

Do you also experience such torque reaction of the plane?
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Old Sep 10, 2012, 08:44 PM
skidding in the sky
WitnessOnly's Avatar
Australia, VIC, Melbourne
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rcfr,

Not uncommon with your power setup to get some torque roll. I add a little asymmetry (in roll axis) to my launches, just to help out.... Without a FPV load on board you can probably launch at 2/3 throttle to minimise the initial roll.

On launch I aim up at about 30-40deg and give it a good firm controlled throw.



At the end of the day though, you gotta get your fingers right back on the sticks quickly either way, might help to get a friend to help for the first couple of goes...

WO
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Old Sep 11, 2012, 07:35 AM
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Thanks, WO.

I have actually flown several time without issue, but with a smaller propeller (4.75x4.75).
It is probably due to the 6x4 that I have the issue.

I tried again today with less power (50%) but still got this torque roll. Each time the plane finished on the back after 2m launch - and I did not have the reflex to take off on the back...

So I'll try to switch the propeller to a smaller one again, hoping that it will be sufficient to carry the 1kg when FPV-loaded. Does the weight of the FPV also stabilize more the plane at launching?

Besides, you mentioned some asymmetry in roll axis. How much angle and in which direction do you apply it?

Thanks
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Old Sep 11, 2012, 09:49 AM
skidding in the sky
WitnessOnly's Avatar
Australia, VIC, Melbourne
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shoot a vid next time if you can...

Rolls left so I generally launch with a 30/40deg bias with the left wing higher, I'm a right hander if that helps with whats going on.
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Old Sep 11, 2012, 12:26 PM
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Was difficult to do a video (alone, no holder for the keychain cam). Will try tomorrow with a 5x5 propeller that I already flew with successfully. Let's see if that change something.

I'll try to record also, you're right it is easier (even for me) to analyze afterwards...
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Old Sep 11, 2012, 04:45 PM
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I'm not a big believer in the 'torque roll' issue. It's all in the throw. Why don't you build a bungee and use that for launching. I do for my wings and it is a perfect launch every time with your hands on the sticks. No stress.
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Old Sep 11, 2012, 06:31 PM
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Australia, QLD, Toowoomba
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I was about to say - Skyfuns are pretty much perfect for a bungee launch, and because it's so consistant, it takes all of the worry out of launching when you're running a heavy payload. It's very cheap to make and it only takes a couple minutes to set up. You can take off with both hands on the sticks and you're in complete control the whole time.
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Old Sep 11, 2012, 08:46 PM
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Quote:
Originally Posted by Gree View Post
I'm not a big believer in the 'torque roll' issue. It's all in the throw. Why don't you build a bungee and use that for launching. I do for my wings and it is a perfect launch every time with your hands on the sticks. No stress.
Can a Skyfun be discuss launched?
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Old Sep 12, 2012, 12:30 AM
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Australia, New South Wales, Sydney
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Quote:
Originally Posted by rcfr View Post
Thanks, WO.

I have actually flown several time without issue, but with a smaller propeller (4.75x4.75).
It is probably due to the 6x4 that I have the issue.

I tried again today with less power (50%) but still got this torque roll.
...
Besides, you mentioned some asymmetry in roll axis. How much angle and in which direction do you apply it?

Thanks
I have several of this kind of plane (radjet800, skyfun, X-830, & the Parkjet which is hardest of all to launch).

Try launching steep and fast, then the roll doesn't matter; it keeps going up even if rolled over, and you have time to get to the sticks. But you get used to it - sometimes I've launched and its rolled upside down on a flat trajectory and I can still fly it out - practice makes perfect!

If its predictably rolling one way you can definitely try angling the throw in the opposite direction. Also be careful not to throw too hard - better a controlled departure from your hand than a more forceful uncontrolled release.

I've never bothered with bunge launches but definitely get a friend to launch the first few times so I know how a new plane will react before trying to launch myself.

Like the concept - can't wait to see some flight footage!
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