Hello everyone. I hope you are all in good health. I am a newbie to this community and would like to grow as an RC hobbyist with the help of the wonderful people here. Kindly bear with me as I share my experience and eventually ask for help.

I got into this hobby by first purchasing a power pack and some building materials. I watched a ton of videos on YouTube from Experimental Airlines and FliteTest and read up on a lot of discussions on our platform and RCGROUPS. I started off by building my first scratch built RC electric plane and it was a grand failure. I built two more planes and they were grand failures too. I reckon I had around 45 seconds of flight, combined.

I acquired my electronics from: robu.in

My constant power pack:
1) Propeller: 7" X 3.8 " CW ABS plastic
2) Motor: A2212 6T 2200KV BLDC
3) ESC: 30 Amperes standard with BEC
4) Rx Tx: FlySky FS-CT6B
5) Servos: TowerPro SG90 mini
6) Battery: Orange LiPo 3S 1500mAh 30C/40C
7) Charger: SkyRC e3AC 3S-2S balance charger

Links to the 3 planes I built in order of trials:
1) Simple prop in slot delta wing: https://www.rcgroups.com/forums/showthread.php?2314379-Central-Florida-FPV-Meet-February-2015
2) KFM2 based flying wing: https://www.rcgroups.com/forums/showthread.php?1252282-24-DS-(Dead-Simple)-Flying-Wing-Pics-Video-Plans
3) The infamous Nutball: https://www.rcgroups.com/forums/showthread.php?836389-The-NutBall-best-damn-RET-foamy-yet

After several failures my takeaway was that:
1) I never really got the CoG on spot or even anywhere near the ballpark for that matter
2) I have to keep the Wing Cubic Loading below 5
3) I have to keep the All up Weight below 350 grams
4) I have to set the throws of the control surfaces to a moderate value
5) I have to use stronger building materials( I used 8mm thermocol without any reinforcement ) A1 sized 5mm paper laminated foam board is quiet expensive and difficult to obtain in our Country. I found a very good store to buy it from though after months of surveying and buying the "wrong" foam boards which were very dense and looked more like poster boards. https://www.vortex-rc.com/product-category/building-materials/paper-laminated-foamboards/

* This is not a paid sponsorship *

After giving up for a while I decided to get back in the hobby and will soon order parts and building materials from the before-mentioned stores as they seem to provide reasonable prices and quality products and very good service post and pre purchase.

I would like to scratch build a flying machine and maiden it successfully. After going through some general construction details and design parameters I decided to build a very simple and "squared" airframe with the following specifications:

1)WINGSPAN: 30"
2)CHORD: 6"
3)KFM2 airfoil
4)Suitable polyhedral
5)1 degree angle of incidence
6)Modular tail section with (12" horizontal stabilizer length 4" chord 12" elevator length 1.5" width) and (6" vertical stabilizer height 4" chord 6" rudder height 1.5" width)
7)Swappable fuselage 23" long and tapered from the trailing edge of the wing
8)Wing placement: 6" from nose to leading edge
9)Suitable down and right thrusts
10)A landing gear as hand launching has not been very kind to my family

I would like to keep the wing loading below 7 so with the specified wing area I reckon the ALL UP WEIGHT should not exceed 300 grams.
The combined weight of the electronics(with cables) is around 150 grams and the battery alone weighs 125 grams(with cable)
I hope the foam board airframe is light enough to keep the All up Weight below the target.

This design is inspired by the NOOB TUBE built by Ed from Experimental Airlines:  

I have invested around 12000 INR in this hobby and hope to get airborne soon and finally taste the sweet success of flying a homemade RC aircraft.
Any help (build plans and tips and tricks)  regarding this topic will be much appreciated.
Please help out a brother have a successful maiden after 3 failures.
And let me know if scratch building the FT FLYER: https://www.flitetest.com/articles/FT_Flyer_Scratch_build would be a better way to start off than the above mentioned scratch build.
Thank you for your patient reading.

There are many good and experienced fliers in Bangalore. It would really be good if you could get someone to check your model, and assist you in the initial flights

We do very much want you to succeed!

Thank you so much for your advice. It's difficult finding veteran fliers in the current situation. I will soon be uploading pictures of the model and it would be really helpful if you could analyze it and give your valuable feedback.

1. There are plenty of good fliers n Bangalore, currently flying. Go to RC Bazaar and get some contacts
2. Anyone who can analyze the flyworthiness of a model from pictures is an unparalleled genius, and I salute such people 

Haha that's true.
I meant to convey that no one would be willing to step out during the ongoing pandemic.
Thank you for your reply. I hope you, your family and friends are safe. 

 

If I build true to the dimensions and keep the all up weight below the target and get my CoG on point and have adequate thrust, is the model likely to fly as a trainer?
Should I bother learning to build a Clark Y airfoil or will the KFM2 with a 40% step suffice for a beginner.

appreciate your opinion!

@SuryaKK,

You’ve done the homework, but may I suggest some points you may like to consider?

1. 350gms (12oz) in a 30”x6” (1.25 sqft) wing gives a wing loading of 10oz/sqft (~30gms/sqdm) and wing cube loading of over 8.5. Or about twice as much as desirable for a (trainer) model of this size.

2. The weight of your equipment will probably be about 60g for motor/prop, 20g for Esc, 20g for servos and 100g for the lipo. Say 200gms. That leaves 150gms for the airframe and wheels.

3. There’s an old well established thumb rule that about 50watts/lb is enough for a trainer. So a 350gm model should fly easily with 30-40w.
Provided the wing loading is in the 5-6oz/sqft (15-18g/sqdm range

4. So the weight has to be reduced and the model size (wing area) increased.

5. A 20gm motor is enough for 50watts. Your 2212 is about 3 times the weight and power.

6. 50watts on an 8v 2s lipo is only 6 amps. So a 10amp Esc, much lighter than a 30a one, is enough.

7. At an average draw of say 4amps, a five min flight will consume only 330mah. So a 500mah lipo is enough.

I belong to the ‘Simplicate and add lightness’ school. You may find the above numbers hard to accept. If so, please take a look at how some of mine fly at 5-6oz/sqft (Yak12, Sunbird, Indore Bipe), and at 15oz/sqft (Pilatus B4). Look for andiyerlko on Youtube for our sub 1min videos.

For an alternative approach, using higher wing loadings and more power, please look at the ‘Builds I have posted’ thread by Mr Rai (sanjayrai55), the coro master. It has links to dozens of his build logs.

I presume you wish to DIY, and have already looked at kits available at Vortex.
But just for fun, you could look at the Apple Box (balsa) kit from Sharma Models, Jodhpur.

Best wishes for your endeavours
Iyer

@ K K Iyer, I can't thank you enough for your valuable response and advice. I will do my best to try and take every point into consideration. I kinda rushed into this hobby and purchased the, let's say "wrong" power pack for a beginner build. I went by the "more value for same price" notion and ended up buying a 3s 1500 mAh when in reality I'm starting to realize it's an overkill for a trainer plane and I made the mistake of buying a higer KV motor, again, going by the same notion. Is there a motor you would suggest that could be used for both a trainer plane and a slightly higher wing cubic loading plane. I was thinking the EMAX 2822 1200KV brushless outrunner would be a good pick and I don't think I have any luck with buying 2s LiPos right now as most of them are out of stock on the major stores with only one 2s 360 mAh available on Robu.in for around 500 rupees while an 850 mAh costs just 520.Should I just go for the 360, if advisable? Furthermore guidance would be much appreciated.
Thank you

@SuryaKK,

Don’t buy any more electronics just yet.

What you have is not an unviable combo. It just needs a different and larger airframe.

Tomorrow we’ll look at alternatives.

Till then, sleep well.

Have a good night, Sir. 

@SuryaKK,

Here are a few models that can be flown with your existing equipment.

VT Allrounder, Super Trainer, Tuff Star from Vortex-rc

Skysurfer, Sky Trainer from rcbazaar

Regards

Greeting, Sir.

I built a smart dart XS with a 38" wing span.
https://www.rcgroups.com/forums/showthread.php?599674-Smart-Dart-XS

I have managed to keep the AUW 375 grams and I am getting a wing cubic loading of 1.6 and wing loading = 3.24 oz./sq.ft.
(Calculated by considering total lift area)

I will be uploading pictures soon and any advice for the maiden would be much appreciated.

Will 200 grams of thrust suffice? I am using a tri-blade propeller I salvaged from a mini drone. I reckon it's a 4 inch propeller with a pretty high pitch. Currently waiting for my propellers to arrive through post. The plane passed the glide test though. 

Some pictures