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FPV wing build thread
#1

I started building this a while back but I took photo's with my iphone at various stages so I could look back at it after a while.

The object of the build is to end up with something practical and usable that flies with little vices and is simple compact and above all tough, aesthetics have taken a back seat.

What could be more simple than a flying wing ?

We used to fly these slope combat wings over on the North shore after work when ever the wind was right, some years back. At places like Newport, (which is banned now as it's so close to the road). Long Reef and Doberoid head and some times near Monaveil hospital, and once or twice from the cliffs off west head, in a westerly it produces usable lift but one mistake and that's it.

It's not just my propensity for recycling that made me decide to use this wing but the fact that I remember it flying so very nicely as a slope soarer. It had almost no vices and was very tough, and could be happily ballasted by using masking tape to hold on sizable strips of roofing lead to the upper side of the wing. This one survived many many missions and the covering was rather sad looking so it was stripped back to the foam core. you can see how yellow it is from UV exposure. This is from exposure while flying as it was never stored in the sun. So well worn was the core that the leading edge needed to be trimmed back and replaced with balsa.

Here's a pic of the core having it's leading edge replaced.

   

The pic shows the core being held down with weights some of which are positioned behind the trailing edge, holding the core from moving back and some more weights pressing the new balsa L E against the front of the core. the glue used to bond the new balsa LE to the core is west system's epoxy mixed with micro light filler. You can see it in the mixing tray in the background of the pic. I really like this stuff for gluing foam and balsa you can use it as a glue or a bog just depends on how much filler you put in.


“The knack of flying is learning how to throw your machine at the ground and miss.”

"When once you have tasted flight, you will forever walk the earth with your thoughts turned skyward, for there you have been, and there you will always long to return."  ~Leonardo Da Vinci
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#2

Very interesting Jason - will be watching this intently!

Steve Murray
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#3

Next it needs a mount for the motor I decided to combine this with another spar. What better place to mount the motor than onto the strongest part of the wing.

This wing already has a spar. It's the black piece of carbon you can see in the pic, It was originally part of carbon nomex pannel that we were doing some NDT on and I recycled it from the bin. However I felt it's not really long enough considering that the wing now has to carry quiet a powerful motor and a couple of 2150 Lipo's and the FPV gear as well. The carbon spar will stay but will be supplemented by another spar that also forms the engine mount

here's a pic of the new spar/mount

   

I'ts a ply and balsa sandwich bonded with the same epoxy microlight filler mix. Note the attempt to spread the load by ending the front and back laminations in a taper and also so the edges don't co-inside to form a hard point at which to fail.

Here's the spar being trial fitted after carefully cutting a slot for it right through the core. Then it's bonded and bogged into the core.

   

same glue mix again Smile the micro light realy does make epoxy much lighter!! Note the weights to try and hold it all nice and straight while the reson cures. Also note that the tips of the spar are bent back slightly this should add some extra torsional stiffness to the wing.

   

Note also the glad wrap to stop the epoxy from sticking the whole lot to the table


   
Here we are with the motor mounted and the trailing edge cut away to clear the arc of the prop.

   

The Motor is a Turnigy 42 40 1300KV with a Turnigy 85 A ESC. The prop combination I have now only pulls about 35A but there is scope for a bigger blade set and more pitch as well. flight testing will hopefully decide the best combination.

Here is the prop it's a folder and I've made a limiter so the blades can't go forward being a pusher I think this might be handy Smile
Also the blades cant go back to far as if one goes over center it will cause a rather nasty imbalance. This addition was machined from Nylon and is simply retained by the prop nut on the shaft.

   

Here's the basic layout of all the parts. The little blue 500mah 3S lipo is to power the video TX the OSD and the video camera. There is also a voltage regulator just to protect the camera as the cheapy one I'm using will not take over 12V. I've already let the smoke out of one of these cameras Wink
Oh and the elavons are on now too. They have simple, full length, tape hinges, are carved from solid balsa and have been re covered with hobbyking Iron on film. They flew with the original core.

   

The canopy is also recycled

   

It was cut out then reinforced with Balsa here and there it's made to kind of hook in at the front and be retained with a rubber band at the back


Here is a left and right pick with the canopy fitted

   

   

She will have two wiglets to act as vertical stabilizers but there will be no rudder controls just elevons.

I'm using an FrSky RC reciever a cyclops OSD and a sunsky 500mw VTX around 1.280 Ghz or there abouts with a sunsky VRX, they have several channels two of which fall into the amateur band. So I will legally be able to use it when I get my intermediate license.

“The knack of flying is learning how to throw your machine at the ground and miss.”

"When once you have tasted flight, you will forever walk the earth with your thoughts turned skyward, for there you have been, and there you will always long to return."  ~Leonardo Da Vinci
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#4

Awesome, I love your work!

I take it you've been looking at Trappy's stuff Wink
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#5

I really like your total disregard for the initial function, carving holes and notches where it suits for your equipment Smile. I really like building and experimenting. When you work from a known good base the results are often quite pleasing - but sometimes terrible.

I hope this build retains all the intended characteristics from its sloping days.

Drew

Code:
---------------------------------------------------------------------
Built-up
Balsa:                            Commercial:           Depron:
Great Planes PT-20 (modified)     HK Hawk 80            Index 3
Indoor Thingy                     Skyartec Cessna 182  
Katana X lite (in construction)   UM SU-26              12"WS Shoestring (Plantraco)
                                  HK Extra 260
and a Fox chuck glider converted to RC
---------------------------------------------------------------------
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#6

(04-04-2011, 01:43 PM)kizza42 Wrote:  Awesome, I love your work!

I take it you've been looking at Trappy's stuff Wink

Oh yes Definatly Trappy is the inspiration behind getting this old sloapy up and flying again as an FPV wing. It's pretty much just what Trappy uses.

The air frame trappy uses is a "Zephyr" by Ritewing
Here's a link http://www.ritewingrc.com/

The zephyr is wire cut EPP foam with carbon spars I'm not sure what airfoil they are using but the plan form is certainly very similar to my wing.
Trappy's motor mount is aluminum and sort of fitted and epoxy'd into the wing in the same pusher configuration as mine. I've had a look at his build threads and they are very nicely done. Trappy also has everything sunken into the wing there is nothing except the camera and the VTX antenna sticking up. So my build is a bit of a compromise of sorts and won't be nearly as slippery as his machines. Trappy uses some sort of heavy covering on the epp as well and has changed it on a later build for some equally unfamiliar covering material. It must work well cause his plane certnly flies the part !!!

My machine is made from M grade polystyrene foam and is cut with an RG-15 profile at the wing root and SD8000 at the tips. It's like this because the SD8000 section stalls at a lower Re than the RG15 section so it helps a lot to prevent tip stall. There is no twist cut into my cores but the elevons are noticeably tapered larger towards the tips. This has the effect of adding an artificial twist as elevator is applied. It's like having washout when you need it, ie in a high G turn, with elevons up, when the wings are working hard at a High angle of attack and then no wash out when your flying fast and flat with elevons at neutral. It's a neat trick of geometry and it really works a treat !! The other thing about this is that it's symmetrical if you do a hard outside turn then the geometrically induced twist produces negative washout and stops high speed stall of the tips in negative maneuvers as well. How nice is that ??

Quote:I really like your total disregard for the initial function, carving holes and notches where it suits for your equipment Smile. I really like building and experimenting. When you work from a known good base the results are often quite pleasing - but sometimes terrible.

I hope this build retains all the intended characteristics from its sloping days.

I hope so too Drew, the thing that has me slightly concerned is that the optimum C of G position will probably change after taking that chunk of wing area out of the back to clear the prop. I'm thinking it should make it more nose heavy if anything, when it balances at it's original place. That's where I'll start and hope for the best. Smile








Here's a pic of the covering finished on the bottom. It's just covered in good quality clear wide packing tape for the most part and the leading edge has a strip of glass reinforced packing tape to toughen the first 2 inches from the LE.

Down the center of the wing is a strip of 1mm ply curved to the shape of the airfoil. Glewed on with the same epoxy filler mix, It acts as a load spreader for the tow hook's attachment. There is a smaller doubler on the inside of it sunken into the core I've marked where it is with green pen so I have a little more meat for the screws that will hold on the wooden skid that also will double as a tow hook for bunjee launching All this is under the tape by the way and the tow hook will screw on outside of the tape. ........ ... ............. I'm not super keen to get my fingers close to that prop going flat chat.

Here's a pic of the under side the c of G is at about the most aft green span wise line.

   

Here's a pic of how the canopy is held on at the back

   

Here is the colour scheem for the top it's red with white stripes.
well a bit of red iron on film overlapping the bare foam and filament tape
one more peice to Iron on Smile

   





“The knack of flying is learning how to throw your machine at the ground and miss.”

"When once you have tasted flight, you will forever walk the earth with your thoughts turned skyward, for there you have been, and there you will always long to return."  ~Leonardo Da Vinci
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#7

(04-04-2011, 06:16 PM)Drew Wrote:  I really like your total disregard for the initial function, carving holes and notches where it suits for your equipment Smile. I really like building and experimenting. When you work from a known good base the results are often quite pleasing - but sometimes terrible.

I should probably mention that I layed out all the parts on top of the wing before I did any cutting. I tried to place them all so that the C of G would come out in the right spot, I knew this from previous flying. This meant holding on the elevons bateries and the motor with some temperary tape for the initial jugeling act. I then marked out the position of each item so I could cut them in.

There is a 10hz update GPS reciever on board, these work on 5ghz or there abouts and are quite sensative noise. I wanted to place it far as from the VTX as possable. It's power comes from the same suply as the camera OSD and VTX. A seperate source from the Motor and ESC. This should help reduce noise as well. It's located just in front of the RC reciever, on the opposate side to the VTX. This is much the same as the set up I used in my EPP FPV power supply wise and even further seperated phicially as far as GPS and VTX goes, so sould it should work OK. Every thing was fine with that set up, tested out to 500m but should have worked to close to 5km, Not that I want to go that far. However I feel you need a bit of a safty margin for these things, after all it's a tenious link between flyer and plane at best.


“The knack of flying is learning how to throw your machine at the ground and miss.”

"When once you have tasted flight, you will forever walk the earth with your thoughts turned skyward, for there you have been, and there you will always long to return."  ~Leonardo Da Vinci
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#8


A bit more covering at lunch time and some hatches
Just the tow hook and the winglets to go and I think that's it ready for a test flight. Oh gotta straighten up the camera as well, It's on a bit of a lean

   

“The knack of flying is learning how to throw your machine at the ground and miss.”

"When once you have tasted flight, you will forever walk the earth with your thoughts turned skyward, for there you have been, and there you will always long to return."  ~Leonardo Da Vinci
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#9

Well it flies !!

I managed to get in a test flight today despite the weather and some small technical problems.

Problem no 1 was I'd set the model up with wing mixing and tested it all then taken the receiver out and foolishly mixed up the servo's leads in putting it back. Fortunately I did check the throws before flying and discovered something was wrong. But this meant a bit of surgery to extract the receiver to swap the leads back to their rightful places.

Problem no 2: All the time the camera was working fine good picture and nice. Then suddenly the camera died and there was only the data from the OSD on a black background and no picture ???? I wasn't going to fly it FPV for this first flight but it would have been nice to have the video recorded just the same. It was not to be. So it was decided to test fly it and see how the air frame would go.

In hind sight it might have been interesting to just record the OSD data but I didn't think of that at the time. I just turned off the ground station and went to the bungee.

Now I have bungee launched gliders before, it was years ago and from a high start bungee not a set up like this for launching EDF machines.

Darren, enthusiastically assured me that it would launch from this bungee no probs, as long as I didn't power up until the to cord had dropped away, commented that "this could be interesting" and offered wholeheartedly to give me hand!! I had some concerns about it being a pusher and it was agreed that things would defiantly go badly if the prop tangled up with the tow line.

Well next the thing I know bungee was stretched the mechanism was armed and my new wing was resting on the launch rails with Darrens foot hovering over the release peddle.

"Fire!!" I yelled and it was away!! Much much faster than I expected, I guess it had well cleared the tow cord when I bent the throttle against it's stop and pulled back on the elevator stick and simultaneously gave a large helping of aileron to counter a rapid roll to the left, I think it was to the left, It all happened at once. Then up it shot into the gray and windy sky. OK got some height now hmmmm but it's badly trimmed need heaps of elevator to hold it level and quite a bit of aileron too. Then I remembered Darren saying "I'll give you hand" he was a just couple of steps away and watching the model intently. I asked him to give me a couple of clicks of elevator trim while I fought the sticks and I'm super glad he did. "Thanks Darren !!" onve elevator was trimmed I got ailerons sorted and began to shake a little less and enjoy a flight of what must have been nearly 10 mins. This model has over 4 Amp hours of battery so I wasn't in a hurry to bring it down. It flew fast and looked smooth once trimmed and I hammered it around in the lumpy air for a while. I guess it was blowing about 15 knots. After a while I did slow it up a bit with out any nasty surprises it stalled nicely and just nodded it's nose. Memories of slope soaring these wings were starting to come back to me now and I was really enjoying flying this wing again. I still wanted to see how it would handle a tight turn with all this extra weight so I got it up to some pace banked it over and gave it some serious and sudden elevator. It just seemed to hook around the corner like it was on rails just like I remembered. Then I tried it again this time with a little extra pace from a shallow dive on full noise, bank and then suddenly full elevator, It almost did it the wing rolled slightly out of the tight turn but I guess I can forgive it as it's carrying two 2200 3S lipos a 42-40 motor and an 85A ESC plus FPV gear and extra reinforcing to take the extra load. I reckon it's the best part of a Kilogram heavier than it was as a slope soarer. All that was left to do was a couple of practice approaches to get a feel for the sink rate. Landing was a nonevent with power off I just lined it up with the strip and held it off 'till it dropped on.

I'm super happy with the first flight despite the camera dying. After I got home and did some domestic chores I took the camera off and pulled it apart for an Autopsy. There were a couple of damaged components on the board. One that was cracked I could still make out a component number on. 6206A Mind you this was one of the bigger components on this tiny surface mount board it had obviously cracked to let the smoke out and there was another similar sized component same package but cracked and burned so badly I couldn't make out the numbers on it. So being a bit curious I goggled the numbers and found a data sheet for a KB6206

"The KB6206 series are precise, low power consumption, high
voltage, positive voltage regulators manufactured using
CMOS and laser trimming technologies. The series provides
large currents with a significantly small dropout voltage."

Now I'm surmising, with my limited knowledge of electronics, that this might be the camera's on board voltage regulator and Strangely enough when you look at the data sheet I googled it says it's max input voltage is 9 volts. The instructions that came with the camera said it would run between happily 6 and 12 volts and I was supplying it with about 9.5 volts. Hmmmmm bugger

Here's a link to the data sheet the component matches the package type 100% and even has the 33 underneath and to the right to denote 3.3v output. http://www.datasheetarchive.com/Indexer/...73637.html

Any way I'm a little annoyed that now I've let the smoke out of 2 camera's I have another one I might try to set up on it during the week.

Here's a apic of the finished plane minus dead camera

   

.

“The knack of flying is learning how to throw your machine at the ground and miss.”

"When once you have tasted flight, you will forever walk the earth with your thoughts turned skyward, for there you have been, and there you will always long to return."  ~Leonardo Da Vinci
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#10

Although a major cludge, would it be possible to sugically transplant the voltage regulator from the orginal camera? Or, alternativey to solder some fine wires and have a slightly larger off-board voltage regulator?

I know there's another component but one of the cameras may be salvageable.

Drew

Code:
---------------------------------------------------------------------
Built-up
Balsa:                            Commercial:           Depron:
Great Planes PT-20 (modified)     HK Hawk 80            Index 3
Indoor Thingy                     Skyartec Cessna 182  
Katana X lite (in construction)   UM SU-26              12"WS Shoestring (Plantraco)
                                  HK Extra 260
and a Fox chuck glider converted to RC
---------------------------------------------------------------------
Reply
#11

I have always been interested in FPV, missed out on seeing it on Sunday.
So when will you be upto this stage??

http://vimeo.com/18873955

Dynam Pitts 12 EPO
Eflite Advance 25e
HK P-51D Mustang
3D Reaktor
Pitts Python S12 EP 54inch EPO
Kinetic 800

Decathlon EP 62.6inch
Stinger 64 EDF
Spektrum DX6i (mode 1)

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#12

Love that clip AWSOME

One can only hope

I complained to the ebay seller of the camera that their instructions were wrong and instead of saying run on 9-12V it should be 6-9V and they said the would send me another camera. I'm happy enough with that !!

Here's the link to the camera in question on ebay
http://cgi.ebay.com.au/PAL-Black-Wired-C..._Equipment&hash=item230f717ffb

Cheers

Jason

“The knack of flying is learning how to throw your machine at the ground and miss.”

"When once you have tasted flight, you will forever walk the earth with your thoughts turned skyward, for there you have been, and there you will always long to return."  ~Leonardo Da Vinci
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#13

Here is some video I took of Jason's Flying Wing
on Sunday. As you can see and hear it was pretty windy by the time he
got it airbourne.
Bungee launch was very successful if somewhat hairy...Smile

http://www.youtube.com/watch?v=Y190nu6fp4I

Jet Teng L39(Breitling)
Scratchbuilt F14 Tomcat(Pukin Dogs)
Vector X
Eflite F86 Sabre(Taz Tiger)
Qantas Airbus A380(Nancy-Bird Walton)
Boeing 737-800
ProEDF F16
Falcon 120(Gas Turbine)
Fly Fly F100 Super Sabre
Pheonix Tiger 6
VQ Models P61 Night Fighter
CY Models FW190

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#14

Thanks for taking and Posting that Video Paul !!

The launch was pretty hairy and the cross wind didn't help much Smile

Cheers

Jason


“The knack of flying is learning how to throw your machine at the ground and miss.”

"When once you have tasted flight, you will forever walk the earth with your thoughts turned skyward, for there you have been, and there you will always long to return."  ~Leonardo Da Vinci
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#15

I found this on Vimeo it contain's some very interesting information about antenna's and radio reception. Not just aplicable to FPV

http://vimeo.com/8826952

“The knack of flying is learning how to throw your machine at the ground and miss.”

"When once you have tasted flight, you will forever walk the earth with your thoughts turned skyward, for there you have been, and there you will always long to return."  ~Leonardo Da Vinci
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#16

Some video from today

http://youtu.be/2_xDqAirZ6Q

“The knack of flying is learning how to throw your machine at the ground and miss.”

"When once you have tasted flight, you will forever walk the earth with your thoughts turned skyward, for there you have been, and there you will always long to return."  ~Leonardo Da Vinci
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#17

It's great stuff Jason - very interesting.

Steve Murray
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#18

After the last flight there were a few minor repairs, some things came a little loose after that abortfull crosswind bungee launch. These were sorted out and some time was spent making a new canopy to cover the electricals and to mount the camera on. The old one was of thin plastic and was very flexable, thus it vibrated, shook up the camera immage and eventually ended up tearing away in mid flight. Thankfully John had his eye on it, noted where it fell and it was easily retrieved. I hope it still works Smile
must test it out before I go to the field.

Here's a pic of the new canopy

   

I guess it's worth noting that this model is based on the same airfoil and planform as the cores that we recently had cut, mentioned in this thread http://forum.rcflyingclub.com/showthread.php?tid=436&pid=9235#pid9235

The motor is a turnagy 42 40 1300Kv and it's being fed by 2 3S 2250mah Rhino packs in parrelell via a Kforce 85A ESC and will do just over 100 Klicks with the current prop set up. There's a fair bit of more room to prop it up further.


“The knack of flying is learning how to throw your machine at the ground and miss.”

"When once you have tasted flight, you will forever walk the earth with your thoughts turned skyward, for there you have been, and there you will always long to return."  ~Leonardo Da Vinci
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