View Full Version : My homemade parkflyer
guinea_pig2
02.04.04, 11:44
okay im making my own parkflyer, its being made with the remenants of a flying wing reshaped... it has a 3X3 prop being run off a himax brushless which really gives it some juice and it got 3 cell etecs! its going to be rudder elevator.. and if i can make it slippery enough it should be FAST! /ubbthreads/images/graemlins/smirk.gif
guinea_pig2
02.04.04, 11:54
hmmm and i think this propellors pitch speed will be around 85 MPH /ubbthreads/images/graemlins/laugh.gif
guinea_pig2
02.04.04, 12:35
just gave it a powered test glide in the back garden and it went hehe WELL /ubbthreads/images/graemlins/smirk.gif it accellerated and was climbing before i ran out of room! /ubbthreads/images/graemlins/ooo.gif
guinea_pig2
02.04.04, 13:30
im trying but the camera batts are dead so they are charging now /ubbthreads/images/graemlins/smile.gif and my dad isn't here with his really good camera ATM /ubbthreads/images/graemlins/mad.gif
i tell you its a beast /ubbthreads/images/graemlins/tongue.gif
just been out with my Miniwing, and that rips....great fun!!! I love having a field near my work /ubbthreads/images/graemlins/tongue.gif
guinea_pig2
02.04.04, 15:10
hmm had another quick test flight! i think it tip stalls because i got a little speed and tried to turn and it just sorta mushed out of the air in a random roll /ubbthreads/images/graemlins/ooo.gif so im fixing it now. ill get more space to fly in later and allow myslef to goet some more speed before i try turning!
i want to get a pocket combat wing, probably near the same size as a mini wing! /ubbthreads/images/graemlins/smile.gif
yeah the miniwing is 24" and I think a pocket wing is 20" so about the same. If you want a miniwing core set Mike_Y sells them for 20 or 25 quid cant remember which. they are built as a sloper but a quick bodge with a motor and prop and its away, flies on my Heli packs and is great fun. Cof G is a pain to get right and think I will mod mine a bit later to get the motor nearer the middle of the wing.
I have a pocket combat wing.....it's a great little flyer - & yes it is 20".
The critical thing to remember about these small wings is that cg placement is everything!!....& it might be part of your tip stall problem.
guinea_pig2
02.04.04, 16:18
i THOUGHT i had sorted it out but i was obviously wrong! took it to a field put full throttle on and gave it a gentle throw and the thing shot off! i let it gather some speed and it started climbing i tried to start turning but the whole thing just leant back and rolled over and it seemed stalled in the roll and i wasn't able to recover it /ubbthreads/images/graemlins/shocked.gif /ubbthreads/images/graemlins/confused.gif before i could take photos too /ubbthreads/images/graemlins/mad.gif i will try and fix the plane and then take some photos! /ubbthreads/images/graemlins/cool.gif
the cg might be a little too far back.....if you get it back together, you'd be best off trying some low glide/short flights to check the cg & handling characteristics.
It's hard to comment with out seeing a photo - but could also be too much control surface deflection (try smaller throws?)
also - assuming it is a wing....are you using winglets?.....winglets will help turning a lot, especially if they droop under the wing.
guinea_pig2
02.04.04, 19:51
im not actually using a flying wing but am using the wing as part of the plane if that makes sense!
i think im going to stop with this for a bit because i have got this horrible feeling ill bend a motor shaft or something if i keep going /ubbthreads/images/graemlins/mad.gif
thanks very much for all the help! /ubbthreads/images/graemlins/smile.gif
dont stop now, motor shafts can be bent back into shape /ubbthreads/images/graemlins/smile.gif
when do we get to see pics?
guinea_pig2
05.04.04, 21:44
well the planes been completely annihalated! i took it down to a big field full throttle bloody hard launch and it sped off,, picked up loadsa speed! and it climbed!, hurrah i though and initialted the first turn! the response was stupidly high for a rudder and just rolled the thing right over! i managed to roll it back but the plane was leaving me so i tried taking it back round! as i turned all my speed died and a futile full throttle attempt annihalted my plane! /ubbthreads/images/graemlins/shocked.gif so no pics! one buggered pico servo and the rest is fine (broken DD prop tho) /ubbthreads/images/graemlins/frown.gif
Sounds like you need the same sort of plane I do.... indestructable /ubbthreads/images/graemlins/smile.gif
I just ordered a couple of these (http://edgerc.com/pcw.htm). I spoke to the designer this afternoon, and he was telling me about his testing practices. 60ft WOT straight down into the bed of his truck.... no damage! Its all EPP with a CF spar, and uses similar tail motors to our helis. The best part is, he hinted at a brushless drop-in replacemnt for the gws50 motor coming in the future. Hopefully it pans out and will work as a replacement for our tail motors.
guinea_pig2
06.04.04, 14:51
yeah ive always wanted one of them, hedgehog and me have been planning to get some for quite a while now! /ubbthreads/images/graemlins/cool.gif
I have a PCW - it's a great little plane.....& it does take a bash well - I'd advise crashing on grass though & not a hard surface.....mine actually stuck nose in the mud once - picked it up, threw it & flew straight away.
The cg is critical on these things - it changes the way it flies very dramatically...the slightest change can make a lot of difference - you need to experiment!!
guinea_pig2
09.04.04, 10:48
cool, thanks for that! i used to have a swift flying wing which was also very sensetive to Cof G changes!
one more question though! on 2 Cell 1200's would you say the 40 minute to one hour flight is possible on one of these things.. WITHOUT killing the cells?
thanks! /ubbthreads/images/graemlins/cool.gif
I've got 2x1200 etecs in mine now....Haven't flown a whole pack out yet - I've had 15-20 mins flights then landed & gone home....think I put about 500 mAh back in.....so yes 30-40 min flights should be fine
guinea_pig2
09.04.04, 22:21
excellent /ubbthreads/images/graemlins/smile.gif i think hedgehog shoud practise flying his slow stick a bit more before one of them..... /ubbthreads/images/graemlins/cool.gif
guinea_pig2
24.04.04, 13:59
okay so ive made another one, purely out of depron and EPP, no carbon at all, just a little stick of balsa to mount the motor on! it is powered by an EDP 50 on 3 cell liths (will change to 2) and has had stable powered test glides! /ubbthreads/images/graemlins/cool.gif bade out of half a sheet of depron! /ubbthreads/images/graemlins/laugh.gif http://www.guinea.rchomepage.com/images/Plane.JPG
Whoa - large picture /ubbthreads/images/graemlins/tongue.gif
those control rods look a little iffy to me....they should at least be the same on either side - you might have introduced all sorts of nasty differential.
Also the elevon hinging looks a bit suspect as well - packing tape would be better than sellotape.
Other than that looks pretty good - is it undercambered or does it have a bottom skin as well?
guinea_pig2
24.04.04, 22:18
it is semi symetrical, sorted the elevons, and flew today! 10 minutes into the flight the motor started glitching and stopped, it was quite hot! i let it cool and it ran happily again, BUT started causing glitching, im trying to attach my himax motor to the airframe now! it flies so well! /ubbthreads/images/graemlins/laugh.gif
guinea_pig2
24.04.04, 23:55
okay himax is attatched and the power is scarey in comparison! did a few test glide accross the garden and it still glides well, so flying shouldn't be a problem! the elevons even when enlarged don't do much! will increasing their chord help with the roll? the pitch is effective so i have reduced the travel to 60% /ubbthreads/images/graemlins/laugh.gif ive sorted the pushrods now aswell! /ubbthreads/images/graemlins/cool.gif the airfoil is almost symmetrical! /ubbthreads/images/graemlins/laugh.gif ive also inserted a stronger spar along with the EPP one, its a small piece of wood, VERY stiff wing now but it still has a bit of give for crashes /ubbthreads/images/graemlins/laugh.gif
all this has increased the AUW to 244g which isn't bad considering ive got a FAR more powerful motor and am running 3 cell lipos, ideally i would like an EDP 50 on 2 cell 1200's /ubbthreads/images/graemlins/grin.gif but this rocket ship is fine for me /ubbthreads/images/graemlins/laugh.gif now, do i have a 3X3 or 3X2 prop? i think ill start with 3X2 so i get more in flight thrust! /ubbthreads/images/graemlins/laugh.gif
Silvashadow
26.04.04, 23:29
Hey Guinea_Pig nice one. Increasing the chord of the elevons may help but not alot IMHO. You would be far better moving them outboard toward the wing tips or maybe just increasing their span. However if you increase either the chord or span the pitch response will increase aswell so be carefull.
guinea_pig2
28.04.04, 18:58
i must report that this plane died a horrible death recently! i was flying inverted in my back garden with a himaxx brushless on it /ubbthreads/images/graemlins/blush.gif (stupid i know) and i dodged the nearest tree and hit a climbing frame at a VERY high speed /ubbthreads/images/graemlins/tongue.gif there were only pieces left /ubbthreads/images/graemlins/cool.gif
COOL! /ubbthreads/images/graemlins/tongue.gif Destruction!
Pictures?
guinea_pig2
30.04.04, 20:41
i will try later /ubbthreads/images/graemlins/laugh.gif ill see whats left :P
Heres a piccy of my latest flying vehicle EPP wing Clic. Shown here with the weedy GWS motor but I've got a Johnson 250 on it now and its a sky rocket /ubbthreads/images/graemlins/shocked.gif
Edit
Bugger wouldnt post the image, rats
guinea_pig2
14.05.04, 09:27
could you send me the image?
guinea_pig666 at hotmail.com /ubbthreads/images/graemlins/wink.gif
vBulletin® v3.8.6, Copyright ©2000-2013, Jelsoft Enterprises Ltd.