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.

Quote from: naatumach on March 06, 2010, 11:15:25 PM
not using an aerofoil... doesnt that actually create a problem?

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

Quote from: vinay on March 06, 2010, 11:31:18 PM
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.

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!!