I had a curiosity from last few days, What difficulties somebody has to face while flying an electric RC plane with much greater wing loading.

For example 13 to 16 oz/sq feet or even more.

This question may be stupid but just want to know the answer. The question came in because mostly the RC planes we know on the internet have wing loading around <5 to 10 or at most 12 oz/sq feet.

And we say less the wing loading, more will be the lightness in air or more easy to fly.

Now if it is difficult with heavy wing loading, then what are those difficulties (Consider we have enough power required to maintain desirable speed.)? Sorry if question seems stupid, Never flew a plane with wing loading more than 9~10 oz/sq ft.

Thanks.

Only thing is u need high rpm motor and good airfoil to avoid stall ..... stall most common problem as I have flown all my 2-3 planes above wing loading of 12 oz/ft^2

Thanks. I am planning to use this motor. I will run it with this 8x6 3blade propeller. Hk also sells this prop's pusher version, So would be good for me. Battery would be 2200mAh 2S 20C Lipo with two 25-30A ESC. It should work?

After a long long gap, Here is all new version of the B25J Mitchell that I finished designing recently.







You can download plans:

A4 size

Full size

The reason I did new version of the same plane is "To improve the previous one as well as to make it more easier with the usage point of view.

As I have already started to build the B25 with the previous plan, I found some flaws in design that needed to be improved.

First of all, "The weight". The weight was more than I expected. I hope new one turns out more light in weight as the Fuselage Vertical and Horizontal plates are thinner than before.

Second "Space", The previous design was not too good when it comes to space. "Space" to put electronics etc. And That is how this one comes out in a Boxed construction. That yellow box visible in above pics greatly minimize this problem as you have all the space from Left side of Fuse to Right side of fuse. To be noted, Previous design had this Vertical plate running to whole length of fuselage which divides the usable space in two portions, Same thing was with that Horizontal plate. This was not any problem when it comes to flying characteristics but then how you going to install that long battery in. I mean, this is not a good idea to install the battery on either side of vertical plate. It affects the stability a lot. And you need more weight to balance the CG on Roll Axis. In second image, It is clearly shown "How much space now it has". Now it is understood why this design is more easier with the usage point of view.

Third, "Access". As it comes to access, Previous design was considerably not so good. In new design, There are two things that are removable for the Battery and servo access. "The Cockpit" and the "main canopy". Main canopy is supposed to be made by foam block(or multiple sheets laminated together). It will be secured on the fuselage above the wing by the means of self tapping screws and 2mm Plywood. This will make two things more easier. Whole wing can be detached for the transportation and replaced before the flight in upper direction w.r.t the fuselage as the engine nacelles don't allow us to slide the wing out from either side. More on it needs to be explained briefly and will be explained for sure if somebody needs an explanation. The Cockpit is supposed to be made with clear PET film to add more scale to this already beautiful warbird. This way, The cockpit will be hollow and we can put a pilot, an Instrument panel or a FPV camera for the "Pilot View" flight videos. The cockpit is also removable and will be also secured with the self tapping screws like the main canopy. I made the cockpit removable so, we can make two cockpits one with a FPV platform and other "more scale with all the scale things inside" and can use anyone of them as needed. Other and more important reason is "to make Nose wheel steering servo accessible which comes just under the cockpit".

Hey wait, There is a fourth as well.  This version also features the new "Nose" that is more sharper and smoother than in the previous one (Third Image). I don't know how that nose in previous one was left by me like that. I guess I was in dreams that time so I didn't notice. Now, The new nose of our B25 is more accurate to the original B25J Mitchell.

I guess it is pretty much like a "User Manual" I just typed. 

I hope somebody desires to build this plane and may build more faster than me, so we can have a new build thread on our own forum.

 

@ Roopesh Sir: Thanks a lot Roopesh sir.

@ All: One more thing that I want to say, "Your suggestions regarding the design and construction are always more than welcome".

If you have any confusion in anything in this design. Just let me know, I will try my best.

Thanks.

Hey sumeet,
nice plane and nice plans. 

Have you completed this build? How did you cover fuselage?
post some pics while covering if possible.

Quote from: Sumeet on January 25, 2012, 11:10:19 PM
I had a curiosity from last few days, What difficulties somebody has to face while flying an electric RC plane with much greater wing loading.

Regarding flying high wing loading plane, what my experience is, you should be good at controlling plane using rudder as response by ailerons is little slow while takeoff and landing. Also elevator and horizontal stab should be strong and very properly hinged to provide sufficient pitch response. While take off, take good amount of run on ground and let the plane take off on it's own. Dont hurry to take off by using elevator. Use precise angle of attack to lower the risk of stall while landing.

Oh, Thanks Spitfire.

No, I haven't finished building it yet. For covering the fuselage, I will use 3mm Biofoam sheet. Its just Hit & Try, Just roughly measure the portion that you want to cover. Cut the same dimension Biofoam sheet. Then, cover one side of it with transparent Packing Tape. Now Start bending the sheet from the un-taped side. The tape at another side will prevent the sheet from breaking when bent. Now, When the sheet fits good on the fuse and looks smooth and nicely curved, Epoxy it permanently on the fuselage.

Pretty tough and boring though.

And on second thought, I was thinking to finish the whole fuselage using Glass Fiber Cloth over the biofoam skin to get more fine and smooth appearance.

Can anybody tell me How much weight it will gain after fiber glassing and what is the correct method to do it right?

Look at here
http://www.hobbyking.com/hobbyking/store/__10905__Glass_Fiber_Cloth_450x1000mm_18g_m2_Super_Thin_.html

It is only 18g/m2 and pretty cheap. Shouldn't add much of wait. Covering with this one will be easier and quicker than biofoam.

Here is a blog explaining how to cover with fiber glass cloth.
http://www.rcgroups.com/forums/showthread.php?t=184236

I think there is a confusion. What I know is the Fiber Glass Cloth can be applied only on Fully sheeted foam or Balsa surface. That means I would have to skin the fuselage first with 3mm Biofoam and then I would have to cover it with Fiber Glass Cloth.

Good thing is I have already ordered Fiber Glass cloth and Finish Cure epoxy from Hobbyking. Just waiting for the parcel.

Thanks for the links.
Cheers.

I'm speechless and I don't think I am qualified to comment about this piece of art. Bravo!

Thanks VC Sir, You are the inspiration for me and most of others in this world. And you are far more better scratchbuilder than me. That way, You have the right even to deny my design  .

And yes, Sir do you have some previous experience working with Glass Fiber Cloth? I wish to learn something more.

Unfortunately, thanks to my laziness, I have no experience of FG. All the stuff has been lying with me for the last year or so and they have, possibly, gone bad.

Oh. So, I would have to test all my FG stuff on a test piece before applying on the whole plane.

Thanks anyways.

Hello fellas after a long time.....

While I was away from R/C and RCI due to studies and other more essential things, I was working on more new aircrafts that I wish to build once I settle down. So enjoy the screen shots and as always.....
"Comments and suggestions are more than welcome."

Thanks.

1. C2A Greyhound (Wingspan 48")
(Real pictures)



(Design Pictures)







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2. Based on the "Swan" which is a bird....All new "Swan 11P".
(First picture: how a swan look like)


(Design Pictures)



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3. P47 Thunderbolt (48" Wing Span)




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4. "Sea-duck" inspired from the plane in Cartoon series "Telespin".
(Wingspan 48")
(Picture if you don't know what is "Telespin")



(Design Pictures)






Well, The plane in cartoon was a twin but the design features only one engine(Motor) that is setup in Pusher configuration. I had "what a beginner needs" in my mind while designing this.......
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5. B17G Flying Fortress (57" Wing Span) (Finished)
Doesn't need a real world picture as it is much famous......

whoa !!! Fantastic. . Just curious :  how long does it take to make reality out of these plans, (at least some of them..)? I wish to see the transformation from close quarters, God willing.

Sumeet.. you are awesome inspiring one among us.. and great art and efforts.. no words to say.. and once again.. amazing works..

Thank you...Thank you...Thank you...for all who appreciate my work!!! 

Thanks a lot.

@Essaargee:

Well..lets count as now I am curious too....

Suppose today I have plans for C2A Greyhound ready to print.

I will spend around 1~2 hrs to closely stick the tiled plans together. This is the most boring thing in any build based on plans. Then around 1 hr to precisely cut each and every templates using scissor.

Now comes the real and most important part.....Cutting the foam according to those paper templates and then labeling them so I don't mix two similar looking parts. Cutting should be done precisely and as per the plans, Failure in doing so may end up with wastage of foam and time. Lets count 2~3 hrs in cutting operation.

Till now, around 6 hrs passed.

Then comes my favorite part in building that is, "Fuselage Assembly".
It seems too tough but once you know which part is what then it is easy. Suppose ~4 or 5 hrs in assembly. After this stage, the plane's fuselage comes in shape.

Next thing is "Wing". Cutting spar, ribs etc require time. Forming the Wing (For me) takes around 2 hrs at minimum. As Foam is a fragile thing, It needs extra care while bending foam in shape of Airfoil but 2 hr is enough for most of the builders. After the wing is completed, I spend some time to make sure that it is not warped, The outer skin is not leaving places at the edges. Then I hold the wing near one of its tips and pretend to play few shots in cricket with it (Not with a ball coming towards me obviously) to check if it can sustain the G force while in flight. Barely "half an hour" is enough.

Now tricky thing is to fix Wing on the Fuselage either permanent or temporary. another half an hour is enough for that too.

Till now...around 14 hrs are gone.

Now, Cutting firewalls out of wood, Installing control linkages, Installing electronics, soldering connectors, testing the mounts, fixing Landing gears etc takes approximately 4~5 hrs at max.

Now taxi the aircraft on the terrace to observe turn movements on ground, Vibrations, loose bolts and screws, Testing control surface movements etc and then trimming of faults takes around an hour.

Once the plane proves itself reliable and strong, It is fit for flying. Now comes the second most boring part...Skinning whole fuselage. Takes most of the time. Lets say around 6~8 hrs. Skinning needs patience as it is all Hit and try thing. You need to stay cool if the skin part you cut doesn't fits properly on the place. Sometimes it takes 10s of attempts to do it correctly while sometimes it fits at just once.

Our stopwatch has now finished its 28th hour.

Once everything above is finished. I can now say its "Ready to fly". I then ask mom to find any flaws in its shape.

Charge batteries, perform instant checks at the field and Maiden it.
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Roughly, 30 hrs.

Now as I am an student, Lets suppose, I can save 2 hrs everyday for the hobby. So, 15 days or at max 17 days are sufficient if I have every required thing in hand. Well its just a rough idea. Even I may take more or less time in transforming one of those plans in real. It may vary person to person.

I hope this gives you a good idea of time, essaargee.

Thanks.
Cheers.