RC India

I was very much impressed after seeing Sukhoi T50, PAK-FA. So decided to build one from 5mm BioFoam!!!!!! It almost look same as F22  :headscratch: :headscratch:

I could not find any plans so downloaded few pics and started creating vector drawing in CorelDraw  :banghead:. Initial drawing is attached

i made it with 25" wingspan. Just finished cutting. But not sure when will I complete it... :giggle:, as don't hav much space in flat to keep one more....!!!!!!!!! :giggle: :giggle:

There might be few adjustments while actually building it and may need to be change few things in the drawing, that will be included in my final design. But I am attaching initial design in PDF and cut pieces in this post.

Will keep on posting as I progess...

Specs: wingspan 25"
Motor: 2212/06 2200 Kv, with 1600 mAh 3s Lipo & 5.5x4 or 6x4 prop
Servos 2x 9hxt with aileron/elevator mixing

Most probably painting in gray.

some more

Now thats I call Scratch Build!! Good going Ashish!!

Great going!! Put up a full log and a finally a video!!!!

many thanks Ujjwaana, Flyingboxcar,

will keep it posted, as i progress!!!!! currently i hav cut everything little oversize, so that i will hav room for adjustment once i am sure will post new plan!!!

cheers
Ashish

Scratchbuilder's dream! All the best!!!

thanks VC

progress..... still going on slowly.... after office hrs got some time so started joining all the parts and finalizing the design.

decided to make single axis thrust vector for this, along elevator. so designed and completed thrust vectoring unit.
below are the 2 videos, 1st for TV unit held in my hand and other one is after fitting it on PAK-FA..

soon will post detailed pictures on how it was built....
components used are 10 mm pinewood stick, thanks to Angad. used U-shape aluminium bracket for motor mount, is easily available in any aluminium shop, for axis used 24gm motor shaft (3mm). this motor was burnt in my earlier project, used bearing as well along the axis retrieved from same motor... used 15gm metal gear servo from RCtimer.

and of course most important my dremel helped me a lot in building this unit!!!!
here are videos

http://www.youtube.com/watch?v=Tls1aNyjuZY

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

WOW  :o  :thumbsup: Simply Amazing  {:)} :salute:

Bravo! I have lot's to learn from you.

:headscratch: :headscratch: :headscratch:

after seeing ur builds  :salute: :salute:, i think its otherway round!!!  :hatsoff:

Congrats Ash! this is an amazing build! You TV is perfect. Use of BL Shaft and bearing is a perfect plan! Do share the experience. What mixing are you planning for the TV?  360 deg TV would be even more demanding. All the best!

cool build {:)} but does thrust vectoring works without EDF unit
you should post the flying video

Ash, how are you calculating the torque required for the TV servos?

thanks for complement buzz, pankaj, dinil!!!

yes, TV do also work without EDF

@ Ujjwaana,
thanks buddy.... little bit overloaded with office work... will soon post details pictures of my TV system.
abt mixing i will be using gear channel on my DX7 and mix it with elevator, around 50% and 70% with flick of switch.
initially planning to maiden it without any vectoring and once comfortable will activate it in flight.

abt 360 degree, yes it is my next project, will mount it on my laser cut Su37 (WS 28").
but i am still struggling to build/design 2 axis mechanism for 360 degree movement.

but had few ideas...lets see....

Ashish

@ Pankaj,

ur build is amazing!!!!

for servo selection for TV, i dont have any formula for calculation, just observations from few threads. but after seeing thread from Dave (rcpowers), he has used hitec metal gear servos (either HS 82 MG or similar), say around 18-20 gms with around 3kg torque.
so as per my observation, i am going to use something similar. already purchased these servos
http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=5192

but in ur case, its very huge, i think servos with 30gm and around 5kg torque would be enough!!! and of course it has to be METAL GEAR servo!!!!

one more thing, somewhere i read that for TV system it is not recommended to use prop size more than 6", if u use bigger prop then it exerts more gyroscopic effect on TV servos, so u may have to used good and high torque servos

hope this will help!!!

Cheers
Ashish

Superb mechanism..looks very sturdy.Would be intersting to see this thing fly. {:)}

kudos sir...

Sirjee, unit lagao aur maiden karo. She will be a stunner and a beauty.

@ROOSTER, naatumach & VC

thanks guys!!!!!

i am little overloaded with office work, so still not completed this one  :banghead:

but will definatly complete it and maiden it!!!! i am also very much eager to see it flying.....my 1st TV project!!!

here are some detailed pictures of TV system

Some more

Here are some pictures of progress on plane

1st pic is final design, and cut pieces

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woah... that is very neat! are you using a pusher prop? or a standard prop put reversed? does it really make a difference?
waise... dont you think, the "belly" of your model resembles a raptor than a pak-fa. The twin engine PAK-FA has two separate intakes with a channel in between resembling a Sukhoi-30, whereas the raptor has an internal bay in that region. With a similar planform this is what i feel really would differentiate between the two.

i am using normal prop, with motor mounted backwards, and rotation is in opposite direction, so it will be normal prop in Pusher config!!!! it hardly make difference if u use pusher prop or normal prop with changing motor rotation!!!!!

abt belly, like most of my earlier builds, and different design studied on internet, i prefer to keep design simple, instead of making it complicated, also u get plenty of room for electronics...

Quote from: ashJR7202 on July 16, 2011, 01:40:37 PM
it hardly make difference if u use pusher prop or normal prop with changing motor rotation!!!!!

I agree, but some people speculate that it makes a difference.Logically, I feel it shouldnt make a difference, thanks for confirming.

Although i would like to point out that this in not the case with brushed motors. They can have different speeds in opposite directions.

Active control tech(ACT) provides for directional stab on Pak fa. In an rc without fin will be an issue even with gyro. Take care of this aspect. Ther are alternatives . Can Be discussed

Hi gusty sir!!!! ACT, no i m really not aware of it !!!!

but will it affect RC plane!!!!! Abt vertical fins, yes i will put them but it will come in the end, bcoz it is very easy to store and handle while building plane without rudder/fin. it will be mostly non moving!!!! will see how it behaves in high alpha, if i found that nose is falling then will try to put some rudder control with gyro also!!!!

pls advice!!!!!

Ashish

Fin is for directional stab i.e so that she doesn't depart directionally. Nose drop is essentially longitudinal stability issues. Low chord fin will make the airplane depart at even at slight high alpha. Consider two ventral fins as well. Short chords will do. Ventral fins aren't masked at high alpha.. Believe me you can show off a small dorsal fin and yet have good stability. No gyros required. Submitted for consideration :giggle:

agustinev,

talk sense man!!!! by that I mean talk in a language that a dummy like me can understand :D
ACT , two short ventral fins etc.... D-UH What?

@ Pankaj!!!!

ventral fins are pair of small vertical stabilizers beneath the fuselage. acts as stabilizers only!!!! during high alpha maneuver rudder is covered by wing and is not much effective, so to provide stability these fins are very useful!!!!
otherwise directional controls become very difficult. without which nose tends to fall down....

@gusty,

i havnt planned for ventral fins but, lets see how my maiden goes, depending on that may add some. little worried abt how my maiden with TV goes  :headscratch: :headscratch:....not sure if i will be able to handle or not  :banghead:....
more over to secure belly while landing i have already put skids protruding beneath fuse, close to rudder, it may work as fins as well.... will post pics soon... it is abt to complete  {:)}

already attached elevators, need to connect push rod and rudder and fix location for battery and it will be ready for maiden...... but i think will be able to maiden only after rainy...

here is the color scheme i have decide, it is almost similar to original, but symmetrical....

give ur comments guys!!!!


cheers
Ashish

Differentiate under And over wing color scheme.
Pankaj
ACT is no big deal to understand. Search will give you plethora of hits . Fly by wire fly by light auto pilot auto stabilizers are some of the examples of ACT

yes sir!!!!! this is from top, bottom will have single dark color, may be dark gray or Black!!!!!

finally, with lots of patience, was able to put some colours on this one.

took few evenings and lots of patience, and Acrylic colours... vertical stabilizers/rudders  are yet to be attached

initially decided to use spray cans but, found that it is not feasible as i needed few shades, more over if not used properly may damage foam....but would have been easiest ways to paint this bird.......

but finally decided to use acrylic colour...... Gray, Black & white....

it is still not in final state...require few last strokes of white and outlines....

though it took lots of efforts, at some places brush strokes are visible, i tried to make it smooth.. but ....some places...

but overall it looks beautiful!!!!!  started to love this bird more and more.... little afraid to maiden this

cheers
Ashish

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Looks good man!!!!

Ash
Where is the fin? Won't she spiral out ?

Gusty

Check post #36. He says they are still to be attached!

Wow nice build, great color scheme looks great, cant wait to see the complete build

:headscratch: would be interested to see how you'd fix the v-stab/rud

Good luck on the maiden flight...

Cheers,
Arun

awesome build ashish... have a nice flight... :)

thanks guys!!!!

soon will be attaching fin, i will be simply stick it on the wing using Evotite and it will be firm!!!!

i hav don this in some of my earlier builds.

after lots of efforts in painting, finally i finished it!!!!  {:)} {:)}

it look beautiful..... may be i spend more efforts painting rather than building it  :headscratch:..... need lots of patience  :hatsoff:......... few wrong strokes and u have to correct those  ??? ???......

so here is my one of the best build......

some more pics from sides

My son playing with motor!!!

The best picture of the among is that two best creation of you side by side.

Your Plane and your Son.

Really looking nice. You should get a Salute from me to allow to play children with the plane. The broad forehead of your son proves that you are really good in creation and beautify them with long patience.

Enjoy the creations.

That looks cool.Waiting for a video.

thanks Kalyan and Foamy!!!

Kalyan thats is really interesting!!!!! and my son likes to rotate that prop so i am little less worried.... took the pic and took my plane away from him

cheers
Ashish

awesome build! :)

GREAT BUILD!!! Waiting for the video. :thumbsup:

finally was able to maiden this one...this was taken 2 weeks back.... :o

it was disaster.... very much tail heavy....as u can see in video.... :'( :'( :-\

from rcgroup i got CG for this plane and balanced it... but it was tail heavy... :banghead: :banghead:

but fortunately.. there was high grass... and no damnage....i am saved..my one of the best plane came out without scratch...

though it landed close, grass was high...so took little time to find it and recover it...

http://www.youtube.com/watch?v=gzxWeFJ2A6Q

Wasn't tail heavy, frame by frame analysis shows you have your full elevator back, she is underpowered, for sure, she has to be flown level then coaxed to climb up, with the present setup, she will fly well, level her out after launch secondly check the winds. It was slightly high, you are better off in the wee hours of the morning,

For you consideration

:bow: :bow: :hatsoff: :hatsoff: :hatsoff: to Gusty sir!!!!

thank u very much for ur analysis sir!!!!!! thats what real experts are!!!!!!!!!! :hatsoff: :hatsoff:  :salute:

it was maiden and was little nervous... so might be in panic i should hav given elevator!!!!  :headscratch:

about power, its the same as my 24" Eurofighter.... and trust me its really good..but yes more weight is added due to TV system soo....thing is that while launching i afraid to open full throttle... fearing something might came off  :banghead:  and may hurt someone around.... ??? so chances are i didnt gave full throttle and then afterwards in panic this thing might hav happened.... though at full throttle power is enough to make it climb at good rate but not unlimited vertical...

i shifted CG forward almost 1-1/2", so battery is almost in the nose.. and it flew very well.......
here is the latest video taken last Sunday ..... though almost same thing happened while launching... :giggle: :giggle:
but was able to control it.....

still didnt activate my TV system..will do it once I am comfortable with the plane.....

once again thanks to Gusty sir....
launched by Saurabh...camera Anand.....
and some DHASU commentary by again Saurabh....
sorry abt the quality...camera was in manual focus and not set to correct focus...

http://www.youtube.com/watch?v=J9AyIFRxY8Q

beautiful flying and fantastic colour scheme there  :hatsoff:

thanks sir!!!

here is the pic taken on the field....

Super stuff, good going

Awesome paint finish Boss!

BEST LUCK Sir, wish u happy landings.:)