RC India

Greetings to all
1. I've started this thread to log a small project that I and my son have started. Will keep it brief and pictorial.
2. The project is right now only on the drawing board.
3. As I'm just a beginner, any input and suggestion will be of great value to ensure completion.
4. I'm also on the lookout for parts and offers to begin collecting my RC gear.

so here goes

First pics are of the design. I used a software called machup which is easy to use. The design is also simple, on the lines of HK skywalker. We started from the wing, gave it the required airfoil and went on to the stabilizers and lastly the fuselage and props. 

A pic of my workspace. Got a room outside the house so no worry of messing up the house.

Since i was unable to find a free software to draw and print the plans, I decided rather to do it the good old way, ie hand drawn.
Google Sketch up does not provide scale printing in the free version so I decided not to spend further time on searching for software.
Here are a few pics of the plan drawing in process. After completion, we stuck it up on the work room wall for reference. 

Here are a few pictures of transfer of plans. Due to the lockdown, i was unable to get large drawing sheets. Had to stick together few A3 sheets that I had. The A3 sheets were only enough for the centre portion of the wings. Rest of the parts were done by sticking together A4 sheets. The drawing of the scale plan was really time consuming and i'm yet to draw the fuselage. Hopefully will get to it tonight.

@bpbeni,
Nice work.
Well begun is half done!

Best wishes.

P.S.
Perhaps you could recheck adequacy of tail parts, especially fin/rudder...

Thank you very much for your kind words and wishes.

Will also keep in mind the rudder aspect during the build. Will try and upsize a bit.

 :hatsoff:

Thanks @unidrakeshrc

have been able to progress a little in the construction of the airframe. The core material is depron and it has been laminated with regular paper. turned out quite rigid.
here are a few pics of the construction in progress

The fuselage has also been built from 5mm depron. Lamination has been done before cutting the shape out of the sheet.
the total fuselage length is 1400mm and the wing span is 1500mm.

Finally installed the horizontal and vertical stabilizers and reinforced the remaining parts.
Below are a few pics of the airframe in crude form. Still a long way to go

The work which is yet to be done are
1. Building of power pod.
2. installing of servos, connecting to control surfaces.
3. building of electronics compartment.
4. Installation of wing mount

Today I ordered some parts from various sites. Major components ordered were
1. flysky TH9x tx and rx
2. emax 2216 with 1045 prop and 30A ESC.
3. balance charger
4. 2200mah lipo, wires and accy

Hi all
 Its been a long and busy couple of months. Somehow managed to complete the build. I'm posting a few pics below.

I found the plane paper laminate to be slightly inconvenient due to the size as I had to join then often. Wanted to try a better option so I ordered a roll of regular brown packing paper. It was much more workable. The brown paper has been used on the fuselage and leading edge of the wings. Over laid the whole lamination with a coat of thin synthetic resin adhesive(Fevicol).   

In this post I will elaborate on the setup used for the aircraft and glide test.

1. The power plant is an Emax brushless 2216 motor with a 1045 propeller. The current set up gives me a thrust of around 650g on a 3cell. The aircraft flying weight is 1.6Kg after balancing. I had to place 450g dead weight on the nose to get the CG balanced. I'm using 2200mah 3 cell Lipo for now and I will plan to upgrade to a 4 cell in a month. The ESC is a 30A BL Heli.
2. The transmitter i bought is a flysky FS TH9x 2.4ghz. I'm using the 10ch receiver. The servos used are 9g metal gear and i placed the servos close to the control surfaces and opted to shorten the control rods. Since the ailerons have independent servos, I have mixed the flap function to facilitate slow speed landing. Setting up the tx rx was easy except for the programming of the independent ailerons, it took a little trial and error.
3. I bought a lipo balance charger and a 6A adapter from amazon. Its working well after a little tweaking of the pins. Also the aircraft has been brush painted with fabric paints available in the market. They're water proof and I guess they would do the job. 

Glide test

4. After balancing the aircraft, testing was done in a field with tall grass. The aircraft was hand launched with correct nose attitude to check the glide slope and behavior. The aircraft maintained both direction and glide slope(nose slightly down). Launched thrice to check behavior and to practice hand launch.
5. Was tempted to do a short flight and I made the mistake of launching the aircraft without the requisite pre-flight checks. The propeller was loose and came off as soon as I launched the aircraft. Though no severe damage was done to the prop or the aircraft, the propeller bolt got lost in the grass. LESSON LEARNT! Will do the necessary corrections and test flight next week. 

https://youtu.be/ZGzR9J2ULPI (https://youtu.be/ZGzR9J2ULPI)

Was able to do the first maiden flight today. The flight was short and I had to bring the aircraft down in a hurry. The tail was heavy and the aircraft controls were sluggish and unresponsive. I decided it was wiser to land rather than force my way with a tail heavy plane.
 I will rebuild the nose and strengthen the tail portion before my next flight. I also intend to make the ailerons a little larger for better response.
Uploaded the maiden video. I guess its quite evident from the video that the tail was heavy. Will appreciate any other inputs for correction from the video.

Doesn't look that bad. Congratulations on the maiden. It seems quite stable to me. For these kinds of pushers 12 degree throws and 30% expo is recommended. Where is you CG ? At the spar?

Much appreciate the input. Thank you very much. The CG is at 20% chord. I had placed one 2200Mah 4cell as the main power source and one 2200 3cell as weight for balancing. The attitude was still slightly nose up. It may have been corrected if I had placed an additional 100g at the nose probably. 
Will repair and try again.

Hi sir,
CG is ok at 20-25 percent.
as said by you there is a lot of dead weight, it will surely impact flying, will reduce flight time.
you can increase the nose section or reduce tail weight if possible.

Thank you very much for the input. I'll elongate the nose for sure. That'll take off the unneccessary dead weight I hope. Will repair and update

UPDATE

1. Finally did the requisite corrections. The aircraft nose was elongated. I built the nose out of insulation foam and it has the added advantage of increasing the structural strength. Also pushed the wings back by a few inches. The airplane looks pretty ugly now but I hope it flies better.
2. Overall the aircraft is much better balanced and I managed to keep the weight same even after the alteration. Also fabricated a roughly built foam structure to hold the transmitter and screen. Will place it at table height when i'm flying.
3. Hope to test fly the aircraft shortly. Will post a video after the flight.   

Hi bpbeni;

Beautifully Built.  {:)}

Regards,

 {:)} Cool keep us updated of the progress.

sahil

thank you very much !!!
Will try and get better at this. Need to work a lot on better building techniques.

Hi Sahil

Will surely keep this post updated. Today I did a second maiden...after two failed launches. Will post it shortly. Do give your valuable inputs.

     
UPDATE

1. Today I took the aircraft back for its second test flight. Corrected the CG by elongating the nose and shifting the wing further back. The first launch ended up in a crash in 2 seconds as I had not powered up the throttle to full. The second launch also ended up in a crash in 2 to 3 seconds as the propellers contacted the motor wiring and sheared it off. Finally did some patch work and got the aircraft up on the third attempt.

The Flight

2. The flight lasted about 2min and the airplane was extremely stable. Post launch and climb, I flew all the way at half throttle. Launch was against the wind and therefore flight in that direction was slower. The return runs were much faster and I was not very comfortable as I need a lot more practice. A few times I had provided aileron inputs in the wrong direction to correct a bank but the aircraft did not bank further and those few seconds we're crucial as I realized and changed stick input.

3. Overall I guess the aircraft is a little forgiving. I need to work a lot on the design and will do so. More than that I need to work on my pathetic flying and practice crashing a little closer next time and maybe some day land the airplane!!

4. Also had one more essential input. I installed an FPV system just for general orientation. The camera was installed approx 60 degrees below horizon which only gave a ground view in level flight. It would have been better to install with horizon for reference when the aircraft is level. Will be flying purely visual for a couple of months but glancing at the screen occasionally gives a great view.

The video 

5. Was taken by my 8 year old son. It has lots of kiddy commentary, please pardon. Also the aircraft view was lost a couple of times. Rest of the video shows the aircraft behavior quite clearly. towards the end I guess I stalled it. The aircraft has flaps and I did not deploy them as I was trying to get it closer. When it got too close to ground, I cut throttle and leveled out and hoped for best. The aircraft is ok. Scratched up a bit but will be ready to fly after an hour of work.



INPUTS at this stage will be valuable. Will keep posting on additions to this particular aircraft. Planning a flight controller after some flying practice.

 https://youtu.be/TQIYoFeDtBI

Huge model!

Nice model, nice flight, nice video, nice commentator.

Here’s a tip.
When she’s flying towards you, move aileron stick towards the LOW wing.
That’s all it takes.

Regards

Bravo. Congratulations. Wonderful kids cheering you up, very sweet.

Now just practice. You picked a good plane, large, pusher prop at the back that makes survival real good.

Enjoy your creation.

Very very stable. Congratulations. Which flight controller you are planning...?

Thank you very much sir.
Amazing tip for flying.
Will keep in mind from next flight and I'm sure its simple things like these that help.
thank you once again.

Thanks a ton @Free Flight

will practice and log in some more flying time.

Thank you very much @shirsa2001
I'm yet to identify which flight controller to install. Was looking for something simple like arkbird but its expensive(more than pixhawk).
I'm in two minds as I wanted to use this platform for learning so I'd rather install something like the APM 2.8 with GPS and OSD.

Hoping that I can build a stronger and more rugged model as phase 2. Will use lessons learnt from this one.
Would prefer installing permanent flight controller on that one. 

This flight is wonderful, brings back memories.

thank you!!!

UPDATE

its been a while and i thought I must update this post regarding my attempt to upgrade the aircraft.

1. After the first few flights, I wanted to install an autopilot and gps. I went ahead and purchased the APM and GPS. I also got myself the mini OSD. Thereafter, I upgraded the APM firmware via the mission planner and tried to get the mini OSD to overlay. But the OSD was not accepting the APM signals and the mavlink heartbeats message showed on screen. I was also unable to flash firmware via the ftdi adapter.

2. I went ahead and installed the whole unit in the airplane and decided to give it a go anyway. Two separate batteries were also installed for the video tx power and motor power to be separate. The whole setup however was a little too heavy for the 2216. After the hand launch, the aircraft would just refuse to gain altitude and ditch. I tried about 6 to 7 times and decided to bring back the aircraft in one piece.

3.    On getting back home, the APM and whole assembly was uninstalled and the next week I flew the aircraft with fpv and no autopilot and the aircraft flew just fine. Still during flight, I felt the power was sluggish but overall the aircraft flight characteristics were really forgiving for a rookie like me! I made so many mistakes but the aircraft gave me enough time to realize and correct.


I guess that will be all for this aircraft. Will keep flying and learning with this one. The construction is such that it can take a beating.

meanwhile i've also started another build which i'll post shortly. Here's a glimpse. Farji talon type... 

‘Farji Talon type’ looks very well made!

A caution - due to steep V tail, horizontal stab effect may be inadequate...

Regards

Thank you very much sir. Every day is a brand new day!! new challenges and so much to learn.

Will increase the V angle and post it under a new topic sir. Still have a very long way to go to complete the build.

Thank you for your valuable inputs for both the builds sir.