Finally finished the airframe and mounted the engine. In keeping with Col. Sundaram's instructions / directions / request, I am posting pictures of her before I attempt to fly her! 

Could have done a much better job had I not rushed it towards the end. I just wanted to get her ready..............

I am calling her "scratch built" for a reason. Though I did use a plan, I deviated quite a bit on the nose section, engine intakes, engine mounting, aft section of the fuselage to name a few. Purists, please excuse.

Construction is out of high density thermocol reinforced with bamboo strips. Fins and elevons out of Depron. AUW without battery is 260 grams.

Hope you guys like her and I sincerely hope she flies  .


Cheers!

VC

One more......... Will post some build thread pics later.

very cool plane

buy how r the sighs made

I think you mean the markings. Downloaded from the net and reduced to semi scale.

Very neat. I bet she flies better than your expectations..

KUDOS!! VC Sir!!!  they look Fantabuls... Hope I finish mine this week end!

I was doing some reading of Andy Lenon's R/C Aircraft Design book for the query you left on my build thread. I guess the sharp edgy nose design you followed would be better for reducing drag and make the effective wingspan more tapered.

One small doubt. Is the wing-fuse section totally flat ? actually the vertically split nose section introduces a little 'curve' in the wing cord, thus forming something like Eppler E214 airfoil (reason some people cut the nose part before the wing break). It is very critical for the effective lift you would achieve and the stall patterns.

You motor pod looks too good! do share the design! any reason not putting the motor shaft aligned to the Fuse/Wing plane ? With CG more towards top, are are making the plane more agile ?

Cool man, you got some good artistic skills... keep goin'!

Thanks Guys! Ujjwaana, give me some time to recuperate, I am pooped and am not thinking straight right now. I have been working non stop on this baby for the last 17 hours. The engine mount was a killer, I will post a build thread on that later.

“Congratulations VC”   Man she is an absolute beauty. I cannot wait to see the results till you get her up in the air.
   
She surely will fly as well as she looks.

Your modelling skill is absolutely marvellous.   Please post some photographs of the under belly also.

Have you decided on where to fit the battery? By the look of it CG surely seems to up ahead. You may not have much leeway to move the battery ahead. You may end up mounting the battery right under the motor mount.

To begin with please surely add some reflex to the elevons. You may trim the reflex down later based on the flying characteristics.  

Wonderfull build. I like the contrasting black and white color scheme.

Fantabulus built..........good luck

Thank you, Thank you, Thank you!!!

Col Sir, my job is to build. As a flyer I am a beginner and rely on others. I am printing out your instructions and am going to pass it on to the Pilot, the day she maidens.

Izmile, inspired by you,  I have just completed a metre long tow glider out of coro. Planning to RC it after initial test flights. Will post some pics soon.

Sandeep, my friend, all the best for your Blu cub, she is looking good and I am learning servo / horn linkages from your photos. Will PM you soon on that aspect. Thanks!

Gratefully,

VC

WOW!!!!! SPECTACULAR........ Really, it is awesome....... Couldn't have imagined a better one....... Fortunate to have seen the various transitions it went through...... Inshallah, she will definitely fly!!!!!!! Fingers Crossed......

Insha Allah ark001! Yes, you have seen the various stages of the build. Thanks for being there. Hope to maiden her soon, want you to be there with me when she takes off or................

Cheers!

VC

fabulous build vc sir
from where did u get the plan??
and of what is it build???
it seems like thermocol
can u post the size and other specs of the model?

Thanks Ankur. If you want the plan, let me know, I will post it to you. Yes, read the initial post, it is indeed Thermocol. The next Raptor will be out of Depron. I have already started the build and ark001 will be building either the Rafale or the MiG 29.

Cheers!

VC

sir please send them to me!!

Length : 29 inches
Span   : 21 inches
AUW (without battery) : 260 grams
2 X 9 gram servos
Brushless motor 2805/1400KV
Brushless - ESC-18A
Master Airscrew PROPELLER 6*4[pusher]
4 Ch Tx and Rx

Battery : Awaiting suggestions...........

What do the experts feel about the above combination?

Can someone suggest the cheapest Battery pack? Once I am sure that she is airworthy, I will invest in the Li Po pack. Right now, for short flight durations, can I use a conventional 6 X AAA / AA Ni Cd 750 mAH battery pack (weight approx 80 / 110 grams). This will push up the AUW to 340 / 370 grams.

Cheers!

VC

Now thats a nice and clean build VC !!!!!!!!!!
 
Great going...

Well VC, thanks for the faith, and sincerely look forward to work on the same..... CONGRATS once again.....!!!!!!!

oh, so sweet  

Can you post some pics of where you have mounted the electronics? Also some pics of the bottom of the wing pls.

Thanks Ankur and ark001!

All the Seniors / Experts,

Please read the specifications of the aircraft listed above and help me out with your suggestions. Does everything look alright to you, or do I need to make any changes? Also please go through the battery issue and advice me.

Regards,

VC

a question to others-using a 2s1p 850mah 20c 7.4v lipo pack will do sir's job or not?

"a question to others-using a 2s1p 850mah 20c 7.4v lipo pack will do sir's    job or not?"

What he is trying to say is :

"a question to others-using a 2s1p 850mah 20c 7.4v lipo pack will do VC's job or not?" 

Vinay, electronics not yet mounted. Will post pics once they are in place.

Dear VC,

I have flown an identical setup of power plant with same brushless and 18 Amps ESC on a scratch built depron Katana with “KF Foil” on the wings with wing span 33 inches AUW 310 gms. Though since it was KF foil it had good lift.

I had used 11.1 V 3S 800 mah and 1000 mah. It used to glide beautifully even at 1/3 throttle.

Your set up will work with 7.4 V 2S 850 mah 20 C at full throttle. Flight will be very gentle you will need lot of reflex at the elevon.

I would recommend you to use a 3S 11.1 V 850 mah Plus 20C Lipo. Weight of LIPO 65 to 70 gms.

Your AUW will be 325 gms.

Thank you Col. Ankurgr8on is offering me exactly the same. Might as well close the deal.

Good night.

VC

KF airfoil
http://cmreel.com/?page_id=82

I deliberately mounted the engine higher to try and save the prop during the belly landings. I had spoken with Ashta Sir before deciding on this and he advised that a higher engine mount would not adversely affect the flying characteristics.
The basic mount is made out of two pieces of 8mm soft wood dovetailed into an L shape. The void is then packed with scrap depron and sanded into shape. Motor is mounted with 4 screws, I have not used any other adhesive to facilitate easy removal. The entire assembly is mounted on the aircraft using high strength double sided tape and is going to be strengthened by 2 wood screws drivem through the bottom.

Some photos of the engine mount.

A view of the final modification made to the model. Note the change in shape of the nose section. Hope this trimmed shape helps in making her more aerodynamic.

And the conversion...........

Bravo VC sir! The way you did the battery mount is coooooool, is it strong enough to hold on on small impacts?

Thanks Vinay! That is something I need to find out. Tried dropping it from a height of 4 feet on its nose (on a carpet) - so far all seems good..........keeping my fingers crossed!

VC

 

Maiden it fast Guruji, cant wait to see that lady fly . take the cam with you when you do so.

Thanks Sahil! Vinay, will do my best.

Cheers!

VC

Havent you shaped the wings in an aerofoil?

Regards
Vaibhav

No. For 2 reasons - (a) Nowhere in the original plan does it call for an aerofoil shape. Saw some completed photographs and didn't notice it either (b) Main body is made out of med density thermocol. Difficult to sand that into an aerofoil shape.

Plan to make further models out of 8 and 6mm Depron. Will definitely attempt aerofoil shapes then.

not using an aerofoil... doesnt that actually create a problem?

I believe many builders dont use aero foil for their delta wing designs to keep it simple. Not sure though. Here is an example:

http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=11058

No aero foil here.

Sorry VC for posting the link but that was the quickest photo that came into my mind. Also that HK bird is no way even close to the one you have created 

Vinay,

My Raptor may be better looking, but that HK bird is 100% sure to fly. I wish I could guarantee that about my baby. Thanks anyway!

Cheers!

vc

Nice job man. Cool plane.

VC ,
Neat Job  firstly .

These planes fly mainly on thrust hence the aero foil is not a problem.
In fact I have heard some  Aero Engineers say that  actually for most Model planes considering the size the aero foil only has a marginal impact  don't know how far it is true

sai

Thanks for the encouragement Sai! And thanks again for calling me today.

Cheers!

VC

In the HC F-22 picture (1st one) did some one notice the lines coming from outer wing break to the mid rib section (Between two tabs/notches) ? one should cut the fuse/wing section along these line and when fitting with the vertical 'fuse' section, the airofoil 'curve' in the chord length is formed by the slant line between the upper and bottom vertical fuse/nose section.  

This  is what there in one of the most popular F-22 plans by Tom He.

http://rc.tomhe.net/f-22

The slant is very minimal to noticed  by naked eye look at the 1 page pdf plan, but while building the plane, one can clearly notice the curve!

Nevertheless, completely flat wings do fly as well. The slight airfoil twist just give   the extra lift.

Sai Sir, you are right. EP power system has a great Weight:Power ratio. The effect the engineers are talking about is referred as 'Reynolds number'.

After 5 months of dithering, I finally completed her today. She is, at last, ready to fly this weekend. I had given her up as a showpiece, however, I resurrected her a fortnight ago and decided to give it one go.

AUW 344 grams, powered by 2s LiPo (to start up and check flight characteristics). All other specs remain the same as discussed 5 months ago.

Posting pictures of electronics bay soon.

Cheers!

VC Congrats. Wish you many hour of happy flying and safe landings.

Please post photographs of how you are mounting the batteries. Since your motor is almost on the CG and space available for battery is very less you may like to mount the batteries across perpendicular to the axis of the motor to restrict weight dispersal at the CG itself.

This is what I expected from a TRUE Champ! Sir, you are absolutely right and my respect for you goes by many degrees today. Without even seeing the model, you have predicted my dilemma. Bravo! I had a trying time, figuring out the battery position.

I have mounted the battery across perpendicular to the motor axis ( the battery is now parallel to the prop - I hope, that is what you meant?) C.G. is just about exactly where the motor meets the motor mount. I hope that is OK?!  Posting photos asap.

Pl confirm.

Regards,

VC

hey VC,

This looks grt!!!!

More like a spaceship!!!

we r waiting for video!!

Absolutely VC, That was what I was implying. Then you are on the right track .

All the best for the sunday

Regards

Sandy

Here we go. Hope I got this right.

VC sir, did she fly?

(Didn't mean to wake up an old topic, my curiosity got over me. That's a REALLY beautiful plane.