I have a 70mm EDF that’s just gathering dust if we want to try something like the FT Viggen.
I can provide the foam and servos if someone can print out the templates.
@Arrgh, I’ll check out the spreadsheet as soon as I’ve got permissions. 
In addition to my previous comments on RCG:
Batteries - use Zippy Compact, they are lighter and usually cheaper. They also puff less than any other cell i’ve used (including nanotechs)
ESC - good to see you went with the Plush recommendation. Those are really nice. You will not need any spares, you will not burn these out and they will not be DOA. Grab a programming card for it, they are like $3.
Motors:
http://hobbyking.com/hobbyking/store/__26988__Turnigy_Aerodrive_SK3_2822_1275_Brushless_Outrunner_with_Short_Shaft.html is slightly lower kv, slightly heavier, but much higher efficiency and will have more thermal mass. With the lower KV you can right a slightly larger prop. You do not need any spare SK3s, they quality is exceptional.
http://hobbyking.com/hobbyking/store/__18115__Turnigy_Aerodrive_SK3_2826_1240kv_Brushless_Outrunner_Motor.html is heavier again, however will let you push 150W vs 70 for your choice. CG may be an issue, use a bigger battery? 
I dont normally deal with anything under a KW or so… so i’m not very good at finding small motors 
XT60s:You only need 2 packs… you have 6 attendees, 5 per pack.
HXT900’s:Get a bunch of spares, they are cheap but you’ll strip them in a flash if you crash on them. Delta/flying wing styles shred servos fast. Consider MG servos as an optional upgrade.
http://hobbyking.com/hobbyking/store/__11854__Corona_919MG_Digital_Metal_Gear_Servo_1_7kg_12_5g_0_06sec.html - digital metal gear. Digital means more accurate positions, much much better centering.
http://hobbyking.com/hobbyking/store/__10345__Corona_929MG_Metal_Gear_Servo_2_2kg_12_5g_0_10sec.html - non digital version of the servo above. Both servos are decent, i’ve used a dozens of them before. I’d go digital just because i’m a snob.
Radios:Get a couple of spare long switches for the 9X, i’ve managed to break all of mine on the 5 or so 9X’s i have and two Taranis… its kinda embarrasing.
Battery charger:DO NOT BUY THAT. Get a proper charger, those style chargers usually end in tears. You have no idea what voltage or amperage they are doing, its a great way to over volt a battery. The circuitry in them is primitive at best.http://hobbyking.com/hobbyking/store/__11060__HobbyKing_ECO6_50W_5A_Balancer_Charger_w_accessories.html is the cheapest viable option. I have one of these in my rocketry and uav field kits for quick int he field charges/topups. These will serve you very very well as they can charge any chemistry and are actually intelligent (ie: wont burn your house down.) Lipos are very safe if you have the right charger and treat them nicely (that being said, I saved myself a few million dollars after a UAV crash where the battery went into thermal runaway by having a fire truck on hand.)
Battery DC supply:Got an old PC powersupply? You’ll get a dozen amps out of even a crappy one. Generic wall warts are not worth using on a battery charger, they rarely do the amperage they are “rated” for and when they do, they get stupidly hot.
I’ve tried to get the formatting right on this by adding a bunch of extra lines and crap… not my fault that the forum software sucks at reading software if this turns into a wall of text. I couldnt paste a link into the browser based one, so I have to use email. sigh.
Also, i’d be shocked if you couldnt get the APC props the less than your cost + shipping from http://www.magicboxhobbies.net/
What do you think of this charger? $9 is easier to swallow than $18. 
Regarding using a PC power supply, that makes sense for charging everyone at once, but not for everyone to use at home.
I finally bought some parts! I’ll be finishing up my Bloody Wonder V2 within a couple months! For those who weren’t at the last SHHH, the airframe is all done, it just needs to have the expensive parts glued in.
I bought everything from AliExpress. All prices are in USD, and include shipping to Canada. A few of these are probably grey market clones of some original gear; it’s hard to tell with AliExpress.
6ch Transmitter/Receiver - Flysky FS-i6 – I paid US $52
Transmitter data cable - $5
LiPo balance charger - iMax B6 - $22 (doesn’t include a 12V AC-DC 5.5mm adapter, those are another $10)
9g metal gear digital servos (MG90S) - $3 each
8x4E Props - $9 for a bag of 5
Brushless outrunner motor: 1450KV 2208-14 - $14
30A ESC with SimonK firmware, 3A UBEC - $6
2 x 1000 mAh 3S LiPo batteries, XT60 connectors - $15 each
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Maybe I’m missing something, but you seem to be missing wings, tail,
and a fuselage.
- William -
Can’t tell by the picture but you’ll likely have to tune the wings a bit depending on your weight.
http://www.pilotwings.org/uploads/2/1/9/3/21932436/4248034_orig.jpg
And your wing’s angle of attack is also pretty critical.
Too much AoA will make the wing stall.
http://virtualskies.arc.nasa.gov/aeronautics/images/StallFormation.gif
It looks like your wings are cambered a bit.
http://upload.wikimedia.org/wikipedia/en/e/e9/Airfoil_camber.jpg
You might want to opt for a more symmetrical airfoil though. Too much camber can create some nasty stall conditions, where as a symmetrical airfoil can be a little more forgiving.
http://code7700.com/images/aoa_symmetrical_vs_cambered.png
And generally you want your center of gravity to be where your center of lift is.
http://amaflightschool.org/sites/default/files/u5/aerodynamics%2025.jpg
Center of lift shifts depending on your angle of attack, but its generally around here.
To improve stability you’ll likely want to increase the wing dihedral.
If you would like I can go over the structural aspects with you in person. I use to rebuild Bell Helicopters (205s “civilian Hueys”, 206s, 212s), and de Havilland Beavers/Otters. I also did maintenance on various Beechcraft turboprops. I’ve done a lot of composite work too. Composites can turn into a real mess if you aren’t prepared and do things in the wrong steps.
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Yes, those things!
@toma, thanks for that. I’m not designing my own airframes, I’m using stuff designed by Josh Bixler at Flite Test. Generally, when I’m building something out of foamboard and hot glue, I don’t expect to get extremely high efficiency or performance.
Eventually I’d like to experiment with in-flight solar charging, but for now I just want to get off the ground, literally and figuratively.
lots of aircraft are built out of foam and glue. Composite materials have high strength to weight ratios.
You’d be surprised how strong you can make something using nothing but foam core+fabric+glue.
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This weekend I finished my first RC airplane! Built it from scratch. I decided to make landing gear so I wouldn’t go through quite as many props.
Although there’s room inside the fuselage for a small battery, I decided to cut a hole, pull out the battery connector and stick it to the bottom with Velcro… Taking everything apart just to change batteries is too much of a pain, especially now that the landing gear are on.
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