RC India

RC Models => Electric Planes => Topic started by: happysoul74 on July 24, 2011, 01:20:07 PM



Title: My Corostick Trainer.
Post by: happysoul74 on July 24, 2011, 01:20:07 PM
[hello everybody!
I am Rajib from Bhubaneswar, Orissa. I have just finished building my frist trainer from 2mm coro. I followed the design & building log of Corostick V2, available on [http://kcrcw.wordpress.com/2010/12/23/48/].
Span - 50 in
Chord - 10 in
Length - 37 in
Dehidral - 10 deg.
Control - Rudder & elevator
Motor - Turnigy 2213 22turn 924kv 17A Outrunner.
ESC - TURNIGY Plush 30amp.
Lipo - Turnigy 2200mAh 3S 25C .
Prop - ZD 11X5.5
AUW -980gms.
Tried to maiden it today, during first attempt broke one prop. as throttle was not sufficient. At second attempt it flew nicly for 15-20second & at a altitude of 40ft(approx.),suddenly the right wing got folded & it crashed.
The prop adaptor& motor mount got damaged.
 Though the excitment & thrill of flying my own plane was for few seconds, I can not express how happy I am.
Soon I'll build another trainer from coro.Any suggesitions/ guidance will be very helpfull for me.
Thank you all rc india members for your supports. :hatsoff:
some pictures :-



Title: Re: My Corostick Trainer.
Post by: SunLikeStar on July 24, 2011, 01:28:44 PM
Nice build happysoul {:)}
Where exactly the wing folded from, can you post picture of the folded wing. May be you just need a better spar to make your plane flyable again.


Title: Re: My Corostick Trainer.
Post by: happysoul74 on July 24, 2011, 01:33:20 PM
some more pictures(after crash)


Title: Re: My Corostick Trainer.
Post by: happysoul74 on July 24, 2011, 01:38:24 PM
Thanks a lot Sunlikestar. I don not think I can repair & reuse the wing. It is completly damaged.


Title: Re: My Corostick Trainer.
Post by: SunLikeStar on July 24, 2011, 01:53:53 PM
Ok, if you are planning to make  a new wing, try making the dihedral support longer, such that it supports atleast half the wing. I'm talking about this thing:
(http://i342.photobucket.com/albums/o417/kaysee_10/SL704079-2.jpg)
You can also use kebab sticks to support the remaining part of the wing.


Title: Re: My Corostick Trainer.
Post by: happysoul74 on July 24, 2011, 02:05:28 PM
God I missed the dihedral support. I used two bamboo stick inside the flutes & three pieces of aluminium wire to joint both the wings & get the dihedral angle but there was no dihedral support.
thanks again.


Title: Re: My Corostick Trainer.
Post by: roopeshkrishna on July 24, 2011, 04:22:49 PM
a nice looking craft friend....and SunLikeStar  a million thanks for the simple but effective solution...


Title: Re: My Corostick Trainer.
Post by: Swapnil on July 24, 2011, 04:58:26 PM
Good one! :thumbsup:
Sad that the wing can't be repaired. Was it because you're using 2mm coro? Because I've used 3mm coro and it's really flimsy as compared to 4mm. At times 4mm doesn't even need reinforcements!

@ Amit sir (SunLikeStar):
The corostick-V2 by 'kcrcw' on the site given in #1 was modified to have a 10o dihedral (instead of the original 5o) for better turns. But I've come across an article that says a dihedral above 5o leads to a decrease in lift. How drastic is this effect?


Title: Re: My Corostick Trainer.
Post by: happysoul74 on July 24, 2011, 06:50:32 PM
I made it with 10 deg.dihedral & there was no prblem at all with lift. Man, with 50% throttle it went up smoothly. About using 2 mm coro, it is really flimsy, but as I could not get any other thickness, I was left with no option.


Title: Re: My Corostick Trainer.
Post by: gurudattapanda on April 22, 2012, 01:53:22 AM
Use thick coro,and I think its available in BBSR as it is in BAM also!! Otherwise go for Scratch Card board (packing box)!! I have nt tried on coro, but soon going to after the Foam flyer get balanced, anyway where you are flying now a days, if interested come to Berhampur on last sunday of month and lets fly togather with my models also.


Title: Re: My Corostick Trainer.
Post by: roopeshkrishna on April 22, 2012, 09:20:08 AM
oh.. with a 10 degree dihedral is it behaving nicely..?


Title: Re: My Corostick Trainer.
Post by: sultan alam on April 22, 2012, 10:21:35 AM
yes i have personally met him and saw that.It glides very nice.


Title: Re: My Corostick Trainer.
Post by: roopeshkrishna on April 22, 2012, 11:37:35 AM
great help.. :salute:


Title: Re: My Corostick Trainer.
Post by: hangingtough on April 22, 2012, 01:27:21 PM
[suddenly the right wing got folded & it crashed.

hi, i have followed the same design and also go my plane wing which folded during the maiden,

Possible solutions
1. The designer has not given enough explanation on spar, length... etc
   - it neads a hanger which will extend atleast the 3/4 th of the wing as you are using 2mm, (i did with 4 mm)

2. My second try was the MOSS design. which is very stable. I could fly it but there was a definate wing flutter which i could not remove even after i got of support from the designers.

3. Dont try single sheet wings on coro, For strength and durability focus on a folded aerofoil design
 - Except that there is a lot of weight concern in that.


Good luck ( See my posts for a general experience)