Su-35 360 VT

ElephantXP
pepper5030:

Я тому и разговор подвожу. Что бы ничего не перепаивать взять акки с нужными разьемами

Это вы зря надеетесь. От пояльника еще ни один моделист не уходил 😃 Да и не такое это уж и богомерзкое занятие - разъемы напаять.

pepper5030

Да не в этом дело, паяльник умею в руках держать. Если есть возможность взять то что нужно, почему не взять? К примеру у вас сгорел какой то датчик в машине, вы идете в магазин. Лежат 2 похожих, одной фирмы. Один точно ваш, поставил и поехал, другой почти подходит только вот надо 2 провода перепоять дома. Цена одна и таже. Какой возьмете? Понимаете о чем я? :)Или нет. Ладно проехали

ElephantXP

Все фирменные аккумуляторы как правило без разъемов продаются. На хобикинге часто идут распаянные, но периодически проскакивают сообщения, что качество пайки плохое, лучше перепаять. И у меня еще не разу не было, что-бы распаенны были те разъемы, которые мне нужны 😃 То сажают папу и маму, а мне 2 мамы нужны, то вообще с диаметром не попадают.

RUCCI4

Аком хорош! еще бы узнать как он отработает свою цену

ElephantXP

Чудес не будет 😃 но и китайской лотереи не предвидится. Для того чтобы такой аккомулятор себя показал, надо будет еще и моторы и импеллеры менять

18 days later
RC4ever
Ротор:

Hello Alejandro!
Welcome to russian forum. Thank you for your film. I think it is the best film about Su-35. It will be very helpful if you share information about composition of your aircraft ( engines, battery, ESC and so on). What is the distance to gravity center? What is deviation of control surfaces and thrust vector control? Maybe you can give some recommendation how to fly in slow speed and at high angle of attack.
We are waiting for your reply.

I’m very sorry that I haven’t answered until now. I have stoped receiving mail notifications from the forum for some unknown reason so I didn’t see I was being answered! 😮

Thanks for the kind words!
I will share my plane setup and experience 😉

This is my current setup for the plane:

SU-35 09/03/2013

Weight
Plane + Rx Battery: 2460g
Main battery: 805g
TOW: 3265g

CG (with gear out)
145mm from CG to wing LE on wing-fuselage joint
170mm from CG to wing LE on wing’s LE end against body

Tailerons trim between -7.5mm / -10mm under wood vertical stabilizer line (aprox)

Dual-Rates / Expos (Futaba T8UP transmitter):
AIL 50/100 -65/-65
ELE 55/100 -40/-45
RUD 70/100 -20/-30

Everyting is stock save for this exceptions:

Main landing gear struts replaced for freewing’s eurofighter trailing link struts.
ESCs fried and replaced them for 70A ESCs from hobbyking, can’t remember the exact model but I can search it.
I put separate wires for Tailerons so that I can use them both for pitch and roll. This is very important for maneuverability!
Reinforced structure for nose gear with balsa wood and epoxy.
I now use an external 15A UBEC from hobbyking to power the receiver and servos separately from engines.
Rx battery → LiPo 2S 600mAh
Main Battery → LiPo 6S 5000mAh
I use 30C and 40C haiyin batteries for the ducted fans, these are fairly priced and great performance, better than Zippys and probably nanotechs too.

In the future I want to replace taileron servos for better quality ones with more precission (Centering and resolution).
I am about to change the stock motors and fans for Lander 68mm 6S counter rotating DPS units. Will try them this weekend if lucky!

As for the travel limits:
Tailerons: I use the maximum deflection allowed by mechanical limits.
Ailerons and rudders: About 30º each direction.
TV: maximum deflection allowed by freewing stock servos.

I often fly on low rates for ailerons and high rates for pitch and yaw, although I set everyting to low rates for landing!

I am using three gyros on the plane (GWS PG-03) that don’t need a sensitivity channel. I used to have them on tailerons for roll and pitch and on TV + rudders for yaw but I needed external delta mixers (V-tail) and these broke over time.

Then I changed them and now I am using 2 of them on separate TV units just for roll (No external Delta mixer!) and the other remains in yaw.

It was more stable in the first setup but it is difficult to adjust and can make the plane VERY UNSTABLE at high speeds! On TV they have a more linear response and can be set easily but is not so much effective. Now I need to put one more on tailerons for pitch at least because it’s easier to fly high alpha and it better holds angle of attack when landing!

I should buy a better quality gyro for this task!

This are my latest videos of the model, I hope you will enjoy them too 😉

Best regards to everyone!

RC4ever

As for flight advices, this plane is pretty easy to fly, the only concerns are take-off / landing and lack of power for 3D maneuvers and high alpha.

Take-off: If you have a paved runway there’s no problem at all just get speed and pull up gently. On non paved and grass runways you have a lot of drag and the plane reaches a lower limit speed on the ground. To be able to take off You usually need a huge deflection of elevator on a quick impulse (If you leave the elevator up, it creates even more drag). So better leave TV nozzles active with full rates and pull up hard when plane speeds up. To avoid entering a low altitude cobra (Not a good thing!) release pressure on elevator as soon as the Sukhoi starts to rotate. You may need to press the nose down after take off to level plane and gather speed, be aware not to crash!
If you can program your Transmitter, optimum setup for take off would be FULL TV pitch up and half tailerons deflection. This is because if you have full tailerons deflection, it only creates force at the begining, then they stop producing lift and create drag that do not help the plane rotate (Detached flow on taileron surface). But if the plane manages to rotate, then tailerons effective AoA decreases and flow attaches again, producing more lift efficiency and suddenly making the plane pitch wildly upwards, maybe entering a cobra (It has happened to me a couple of times). With half deflection you limit the “unwanted cobra” risk and probably generate more turning momentum than with full deflection. Full deflection is needed for crazy 3D maneuvers only 😉

Landing: Set all rates to low. Raise nose and keep some 15-30º AoA nose-up attitude at all times. Let the plane loose altitude slowly. Pull a bit more before touch down to further slow down the plane but try not to stall! If you do this too early the plane will gain altitude instead of landing. You need to give a bit of throttle and lower the nose a bit to prevent it from stalling. Take care to remove throttle as soon as the plane lands to avoid sucking debris and damaging the ducted fans.

3D maneuvers: It is very personal, try always first at high altitude and you can later repeat them lower when you gain confidence.

high alpha: Keep nose up pulling on elevator. TV always on. Try not to touch ailerons, make corrections very carefully with rudders. If plane starts twisting out of control, lower the nose and give power, do not try to compensate with ailerons if the plane’s nose is still looking up. Be careful when you start this maneuver too low since it takes time and full throttle to recover the plane to a normal flying attitude again!

Flat spin: Stall the plane and use maximum elevator and rudder deflection with full trottle to enter spin. Regulate spin speed with throttle. DO NOT touch ailerons at any time!

All of this is what I do when flying but you may find better ways to do it
Each one has its own way to fly!

Philosophy of flight: Since this plane tends to be underpowered (less than 1:1 Thrust to weight ratio) it’s good to learn to fly in terms of energy. Especially more if you want to fly 3D. So, speed and altitude are always your friends, you can always convert speed into altitude and altitude into speed, so before you start a high energy consuming maneuver like a cobra, or a drifted snap roll, you better first gain speed either accelerating or diving. After accomplising a maneuver the easiest way to recover speed is diving but you can only do this if you started high, otherwise you rely solely on motor thrust to recover lost energy. So try not to risk dangerous maneuvers at the end of flight!

A couple of pictures for the nose gear reinforcement mod:
(Balsa wood + fiberglass + Epoxi)

The main landing gear replacement (Though I am using a less diameter wheel)

And finally the current and previous electronic setup:

RC4ever

Спасибо!

By the way, I forgot to share this last mod:
Cockpit painted blue-green, Transparent head up display screen and green LED simulating sun reflex on display screen 😉

Ротор

Hi Alejandro!
Thank you for detailed information about the settings of Su-35, modernisation of the frame, as well as instruction for take-off, landing and aerobatics.This information will allow us move to the next stage. New videos are very good. There is visible illumination in cocpit on your videos. Is it a diode or reflection from pilot*s helmet? What kind of video camera do you use and how to attach it? Do you have experience of flying with help of FPV system?

RC4ever

Thanks Ротор 😃

Yes, I use a green LED to emulate head up display.

We film with Canon EOS 7D from the ground and with hobbyking’s hd wingcam from FPV planes for the air shots:

hobbyking.com/…/__17200__hd_wing_camera_1280x720p_…

We secure the camera to nose of the plane either with velcro or with masking or electric tape.

On the FPV planes we use a separate camera for the FPV purpose, the one on the link is just for recording.

I am still learning to fly FPV on a Bixler plane but I intend to make my L-39 EDF an FPV plane too, but haven’t tried yet (I have like 30 flights on the Bixler but I think I’m ready to move to the jet).

On the air to air video we also used a GoPro hero 3 from an FPV hexacopter for some of the scenes.

Ротор

Tanks Jandro for your information. Are you flying with vision goggles or screen?

RC4ever

I use Fatshark Predator goggles but only on the bixler right now. I pretend to use them too on the L-39 soon. 😃

Ротор

Hi Jandro!
Perhaps there is some risk to fly with goggles without seeing the aircraft from the ground. May be flying through the screen is more safer. What is your opinion on this issue?

RC4ever

It first depends on what is your flight range.
If you are going to fly close, maybe screen is more secure but if you are flying farther than 400-500m you won’t either see the plane so there’s no point in using screen.

If you intend to use a head tracker, you need the goggles too. With goggles you are more inmersed and concentrated on flying and thus you can fly safer.
It is also difficult to properly see anything on a screen with daylight unless you cover yourself and the screen with a towel, in which case you also loose sight of plane.

So I think it’s safer to fly with goggles but if you want to be even safer you can ask a friend pilot to be your copilot and keep always track of the plane while you fly so that you can give him the transmitter if you loose video signal.
You can also do this with teacher-student cable to be faster.

In any case, what will give you more security in flight is to use good equipment (Diversity receivers, multiple Rx good adequate antennas or GPS tracker antenna, OSD + Autopilot…)
This way you first ensure that you have more range but if anything goes wrong you can still hit autopilot or “return home” and wait for the plane to come back until you regain video signal or eye contact.

This, of course, is just my opinion 😉

About the Мотоустановка, I was using the original fans that came with the kit, all posted videos are with these fans. Thrust to weight ratio was about 0.7

This past weekend I installed and tried new engines, Counter-rotating Lander DPS 68mm EDF for 6S Li-Po.

rc-castle.com/shop/product_info.php?products_id=20…

I did some thrust tests and this is the outcome:

SU-35 09/03/2013

Weight
Plane + Rx Batt: 2460g
Main batt: 805g
TOW: 3265g

CG (with gear out)
145mm from CG to wing LE on wing-fuselage joint
170mm from Cg to wing LE on wing’s LE end against body

Measured Thrust on ground: 2200-2300gr

__________________________________

SU-35 19/05/2013

Weight
Plane + Rx Batt: 2744g
Main batt: 841g
TOW: 3585g

CG (with gear out)
148mm from CG to wing LE on wing-fuselage joint
173mm from Cg to wing LE on wing’s LE end against body

Measured Thrust on ground: 2800-3200gr

Please, I insist that you keep speaking in russian!
I will translate and ask by private message if I have any doubt, maybe this way I can learn something! 😁

ElephantXP

То-есть насколько понимаю, с лендеровскими импеллерами тяга всеравно меньше 1 получается?

RC4ever

It would be better to have more than 1 to 1 Thrust to weight but it’s very difficult in this plane. Maybe you could do it using 8S LiPo capable motors in PLASTIC fans to reduce weight and improve power.

I bought the lander fans because they are the only high power counter-rotating dynamically balanced EDF set that I know and is sold at a reasonable price.
The all-metal shroud sadly increases the weight a lot 😦 but they are also very efficient 😆 so I can fly more time than if I use 10-12 blade EDFs.

Ротор

Hi Jandro!
Thanks for yuor opinion about FPV system. I think that flying with copilot using second transmitter is a good idea. Motors for Su-35 is a problem. I think there is no good proposal on the market. When you measured stock EPF trust did you use 10 or 6 blade fans?
When do you need to use tailarons for roll? You said that ailerons should be used with great caution.