HOW TO : Differential Thrust | Flite Test 

Love you guys and the show. without you guys I would probably be out of the hobby. building is what kept me in it

I recently programed my spectrum 6(black) for differential thrust, watching every video I could find. It took two full days. The roller is now hard to use due to wear. Result was a switch was activated in a menu 3 levels into the programing FROM THE FACTORY that prevented success . After all that work I found that flying two motors on one battery (2200 mha 35c) drew so much current (40 amps)that it swelled a battery with each flight. The plane I built was able to carry two batteries in parallel and cured the problem . You really have to want a twin! I wish josh would put a wattmeter on their recommended setup.

this is awesome, I think if more videos were out there like this one, not so many people would stop a 4 channels

Keep up the great work with the videos. You guys got me into the hobby. One suggestion I think you guys should make a video on another day along with a video on Monday and Wednesday.

Really nice tutorial. Keep up the great work guys.

Really enjoy you info videos, I learn a lot from them. THANKS

Great demo and good info. Thanks.

The amount of mixes required for this function can vary depending on your transmitter's programming capailities/functions. One very IMPORTANT thing to have when doing this sort of setup is to make sure you have a receiver that has the proper FAILSAFE functions for the secondary throttle as some receiver will simply HOLD LAST COMMAND which would be very bad with this setup in the event signal was lost.You would get the esc/motor on throttle channel go to low throttle position while the other secondary esc/motor would simply stay running at what ever RPM/throttle you had it moments before losing signal...

I am gong to describe a very interesting problem I had/have using HKing ESC's and a Turnigy reciever, that i think is worth sharing in case anyone else runs into it. I set up differential thrust essentially the same way you did, but one or more of my motors would continue spinning even at zero throttle following rudder inputs. As long as I didn't enable the rudder mix, both motors would start and stop at the same time. If I enable rudder mixing and move the rudder back and forth a bit, many times one or more of the motors would continue spinning at low speed even though the rudder is moved neutral and the throttle moved all the way down. After doing some troubleshooting/meditating on the issue, I came up with a possible explanation. Before you ask, I did all the obvious stuff, ESC calibration, small tweaks to trim and mix settings, and the like. The total travel of the sticks on my radio is limited mechanically by the chassis of the transmitter itself. If I were to take off the front faceplate of my radio, my sticks would have a small amount of extra movement. At some level, the sticks themselves have to return to the computer in the radio a numerical value indicating their position. For my example, I will say that with the faceplate on, my radio delivers a numerical range of -95 to +95, and with the faceplate off, perhaps it delivers a maximum of -105 to +105. When the sticks on the radio are calibrated, the radio knows that when the throttle reads back "-95" indicating the throttle is all the way down. The radio sends a "-100%" signal to the throttle channel, and the ESC's are calibrated to exactly this signal. What I think happens to cause my problem, is that when i'm at 25% throttle, and I throw the rudder hard to the left, the right ESC somehow gets sent a signal that is "lower" than -95. This somehow causes the ESC to think "oh no, I must have been miscalibrated before because I'm getting a new lowest possible reading on the throttle." The ESC seems to on-the-fly recalibrate itself to this new value for "zero throttle," thus when I move the stick all the way down, one or more of my motors continues to turn. My workaround for this problem was to disable subtractive mixing all together. Rudder inputs only add signal, they never subtract it. Since making this change, my motors always stop when I kill the throttle. A more robust solution would probably be to install better firmware for my radio.

Watching videos, 737-800 NGX, I've seen the engine throttles at slightly off positions of each other to off set what I believe to be two problems of flight. One being to off set cross winds and the other to compensate for engine torque. Are there any problems in flight were you would intentionally use a off set in engine thrust for RC Model Planes?

Thanks so much, this video was so helpful!

You should make a compilation of your crashes :D great job as always

hi flite test, can you make a p38 swappable/foamie?

I needed this for my mini kraken!

Love the Flags At the end :) cool video

Aren't you supposed to dissconnect one of the ESC's power leads from the cables when running dual? Not sure if the Futaba ones have some sort of smart power management, but I'm pretty sure you could fry a cheaper reciver if booth ESC's feed power to it.

this is very helpful, and like you said works on most tx,s as I am using turnigy 9xr and 9xr pro would you say this is possible with these tx,s or not if I wanted to use this idea???

What would be a good transmitter with the 4 mixing options. I wanted the fs-t6 but I think that only has 3.

Bugga me, I have ben wondering if proportional throttle was an effect of the circuit board/rx or the transmitter, out of the blue you answered my question ( you popped up in recommended video for you section on youtube ), either you or youtube have phychic powers :), thanks mate this video is awesome. I have bought ( and broken ) enough planes for a lifetime, and am know looking at building flying things with my scraps/parts, if it wasnt for your channel i think i would of thrown them away ages ago.If you ever get bored ( lol ) do one for a spektrum dx6i ( if its possible to program that to do the same thing ). Good job tho guys. One weird thing i noticed about your videos, and its you guys yourselves, even when im watching one that doesnt concern me ( liike im never going to build a star destroyer big enough to launch from a truck, but you guys did ) i find that i still end up watching it as you all seem to have personallities that make great tv. If any one of you move to England could you please apply to host the new Top Gear, the show needs you.

If I have a 10 channel and I bus then would i be able to have flaps, landing gear, etc. also can I do differential thrust on the tgy i10?

How about showing for a Hitech Aurora 9 or HT 7 pro?

I think about getting that radio(newer version). What can you tell me about gimballs how much worse to these feel compared to frsky taranis?

Does it matter which motor is mounted on which side of the wing? I know to run one cc and one ccw motor to counter the torque roll but does it matter which side they should go? CW on left or right ect...

Would it be possible to use a yaw control gyro with differential thrust?

I noticed the radio you are using is very similar to my Tactic TTX 650. I will try the same set up in it. Thanks

@FliteTest What lipo should i use if i fly 2 Motors? I have two 2S brushless motors should i use then 4S and 3S ESC's????

Do i have to cut/pop off one of the + leads for the esc before I connect it to Rx?

Gonna set this up soon on a Bloody wonder twin using Deviation on my 12s ...But have a question on the twin baron what size motors are you using? Looks like a pair of 2204s ?

Please do a challenge where you fly a plane ONLY on the switches on a transmitter. No sliders or sticks.

EXCESSIVELY LOW THROTTLE! Okay, so maybe I missed a post about this, but: I have a Spektrum DX8G2 and I followed this setup. I am flying the FT Sea Duck with the Power Pack C (Emaxx GT2215/09 motors). I tried running a 2200mah 50c 3s battery and it was a pain to just keep the plane from stalling. I tried my 3200mah 30c 3s battery and it was pretty much the same thing. I notice that when I am full throttle and use the diff thrust, one motor cuts down and the other one still revs up quite a bit. This tells me that my issue is the radio setup, not my hardware. How do I set it up so that my throttle is actually 100% when I set it at 100%?

i bought a devo 7 receiver, it doesn't have numbers but it already has names by each port i.e. elev aile thro rudd it only however has one port for the throttle, are these just guides and can i overall these guides, or have i messed up. Kind Regards

Quick question: Instead of using channels 5 and 6, can't I use channel 5 and original throttle? Because then I'd have one channel left for a servo to open cargo doors and what not.

if you're at 100% throttle, is there any throttle "travel" left to go in either direction? Or are you subtracting throttle then? If so, can you only turn in one direction?

Is this possible with the cheap fs-i6 TX, if the model is a wing (no rudder), but with retracts. Or do I need more channels?

Does ESC with BEC damage the reciever wenn i plug bot in ?

Hi guys, I have a problem. I want to do this differential thrust on a resque boat (2 motors, no rudder). Only my Graupner mx16 hott has only 3 free mixes. Can you solve this? Forward and backward. Thanks Herman from the Netherlands

can you do this with a spektrum dx6i - we need it for the sea duck

Very nice and simple video. This is probably a hack you don't read in a official manual. 👍😃😃

Do we still need vertical stabilizer if using differential thrust?

can you fly a plane with differential thrust but with no ailerons or rudder

Is this transmitter good for an fpv miniquad?

Can you guys make more videos with Spectrum controllers and reservers?

Can differential thrust be done with the flysky i6

What if I also wanted reverse? What would I have to change?

Hi Guys I have a Futaba T8FG I have looked the mixing program and I am confussed Can you help Thanks

My radio is hitec flash 7. Its possible with this radio?

Just a thought... ... could you use differential thrust to make a four motor plane, without any flaps at all?

Who has this radio? Can you do it for the 2 common radios? FR Sky or spectrum?

Almost half a million subs

Richard .UK. Please could you show mixing on a Graupner MZ12 Pro. I am using the boat model section none the less it seems to be different to your good illustration ? I have downloaded the manual but it seems to me you need a dgree in physics to understand the instructions.

Can this be done on the new Orange tx6i?

I have 2xBATTERY and 2xESC... can i connect the battery to each esc?

You guys use to be all spectrum. I miss that.

Can you guys please do a review on the new 1.2m spitfire by horizon hobby?

Josh how to differentiate my fs i6 right joy stick thrust

How do you reset the mixes to neutral?

Are the motors spinning the same way

Hi Flite Test, I was in ohio the other day so i ran hover to your HQ and no one was there, so i left something with a note on it asking for you (Josh, and anybody else available) to sign it and send it back, and i was wondering if you got it?

What motors and escs are that?

why am i watching this, i don't even have rc

How do you do this with a tactic ttx660?

God it is very complicated. I know these Graupners are great expensive radios but man these are quite complicated beasts. I did it with my cheap and great FS-i6 which only has 3 mixes and it works!!!!! I used all of the mixing possibilities (it would be nice to have more) but it is just doing what it should, and I only used 5 channels (delta mix + diff. thrust + front steering wheel on the place of the rudder) I still have one more channel for some bomb dropping :-)

What about throttle cut ? without it my fingers feel endangered.

How do you do a Throttle Cut with this setup?

Not many people have this radio. nice to know how to do it if I get one though

Nice one! Can you guys do a review of flysky Fs-T6 ? Really really appreciate that😁😁😁😁

Can I use a kk2 board instead

Is there going to be a Flitefest west

When is this plane gonna be out??

Na, it's just the old people in Germany who fly mode 1. I think the reason why it is default on Graupner, is because it's the first mode. I have the mx20 and I love it!

Now try this with an idle up on a twin variable prop plane. That should make some tight flatspins. If I'm counting the channels up properly, it should only take 7, leaving one free for lights, or gear, or something.

What about removing the power line from one of ESCs?!

1- Isnt better to remove one of the red wires in the ESCs so only 1 bec is providing power to avoid conflicts? 2- Its as simple as use 2 separated channels for motors and mix rudder with each one of them (in the desired direction) and each mix use a switch to enable/disable.. you can play with how much.. a 100% mix would do one motor stop and the other go full whrn using full rudder

Why don't you show us how to program the old Spektrum DX7 for this??? Please??

I want to buy the radio sends to Brazil?

Could you build a 3 propellered airplane with a decent size with differential thrust ?

Are you guys ever going to bring up the USA Today drone again? You said you would. 😑

God, you guys really need to make an me262 kit using this type of thrust

How to throttle calibrate 4 esc's at a same time using flysky fs i6 transmitter if anybody knows about it then please reply me

you've got 2 power supply's going into your Rx possible damage to Rx ???

Wish you'd do some videos on the FS-i6 for us poor folks that can't afford high end gear. Why do you think we're avid Flitetest viewers and foam builders? I think there's a number here that can't afford the "good stuff". I'll admit it, I'm retired and poor..

can u do a tutorial on tuning a quadcopter with naze32?

This is a super late comment but i had to say it because im curious. So i just watched this so i can do diff thrust on my bushmule. However i already have a 7 channel receiver and tenecally i need 8 for the reverse. But i dont see why you guys aren't just mixing throttle to aux 1 then rudder to throttle and rudder to aux 1 its the same thing really just easier in my opinion and 1 less mix and the best still able to use aux 2 for flaps or gear or whatever you need.

very informative viedo but i am trying to do this setup on my taranis to fly my super bee that i built

im going

Would you guys ever consider vlogingOr filming everyday in the office

Can you do this mix on a FS-i6?

There is a bixler3 in the hobbyking store!!!!!!😆

Im using this on my boat

finish the shinden plz

I will Youse it für a Tank and i Testet it with 2 Servos and locked my legt stick Grad it spring back To the Middle the Servos is nor working

The Graupner MZ-12, eh. Guess I gotta buy the White Album all over again ;-)

What is the easy proper formula to app lie for weight of plane to proper KV Size of brush less motor Size..So if I have a 8 lbs plane, what size kv do I need. Keep in mind that I have watched 100s of videos. Ive been searching every where. Why is this information not easily available to all the rc hobbest in the world. Brian. I dont need a treasure hunt! I need an exact answer please. Thanks

Make a quad that you fly around FPV and catch Pokemon with.

too bad im using old futaba 6ex, anybody knows how to do this.........thanx in advance for your help

For anyone using a flight controller (like the eagle tree vector) that doesn't support differential thrust, I wrote this arduino sketch which does the mixing: github.com/fahrvergnuugen/rc-differential-thrust-mixer

Hey y'all should put out the vtol Guinea pig

OK So How I did it with FlySky FS-i6??? Ch1 - AILERON Ch2 - ELEVON Ch3 - MOTOR 1 Ch4 - RUDDER (I put here the steering front wheel as well) CH5 - MOTOR 2 CH6 is FREE (can be used for anything else) We have 3 mixes Mix 1 (we connect the two motors so both works parallel) Mix is ON Master Ch3 Slave Ch5 Pos. mix 100% Neg, mix 100% Offset 0% Mix 2 (we change the MOTOR power as we move the rudder for MOTOR 1) Mix is ON Master Ch4 Slave Ch3 Pos. mix 20% (can be anything from 0-100%) Neg, mix 20% (can be anything from 0-100%) Offset 0% Mix 3 (we change the MOTOR power as we move the rudder for MOTOR 2) Mix is ON Master Ch4 Slave Ch5 Pos. mix -20% (can be anything from 0-100%) (I don't really know why NEGATIVE 20% but it works like that) Neg, mix -20% (can be anything from 0-100%) (I don't really know why NEGATIVE 20% but it works like that) Offset 0% THAT IS IT It works like a charm!!! Enjoy!!!

ER-9x MASTER RACE!!

Bring back the vigen