Help! FT esc reverse?

theSTOL-er

New member
Hi, I have a ft esc in a tutor here and I was wondering if you can put reverse thrust on it for shorter landing rolls.

I fly using a fs-i6x running open i6x (great firmware for it, just like opentx) and have already figured out how to set it up on the transmitter side.

I noticed that the esc runs off of bl heli s, but I can't get it to enter programming mode.

Thanks for the help.
 

Merv

Site Moderator
Staff member
...I was wondering if you can put reverse thrust on it for shorter landing rolls...
It would be possible if the ESC could do that, but I don't think the common ESC can. Maybe someone else knows something I don't.
FT rebrands their ESC's, they come from a variety of manufactures, your FT 20 amp ESC may not be the same brand as my FT 20 amp ESC
 

luvmy40

Elite member
You could, conceivably install a switching relay to reverse the motor rotation, but at what cost in weight? $? is there even a SPDT relay avaialable that could be controlled by your receiver?
 

LitterBug

Troll Spammer
You can put the BlHeli ESCs into 3D mode but it will take either a USB programmer or a flight controller set up in USB passthrough mode to do it. You could then set up some mixing on a switch to enable/disable the reverse thrust portion of the pwm range. Normally ESCs in 3D mode are at 0 throttle in the center of the PWM range... From center to top is forward. From center to bottom is reverse.

There are also some alternative ESCs on the market that have a 2nd connector that will reverse the motor when a switch is set. Those will require another radio channel.

Cheers,
LitterBug.
 

L Edge

Master member
Yes, it can be done.

Hobbywing FlyFun 40A ESC sells one where the direction can be reversed so the prop acts as a brake. It uses an extra channel of the RX and after the throttle is lowered to off, you flip a switch controlling the extra channel (which reverses the +100 to a - 100) and allows you to throttle up.
Had a steerable nose gear and it was even nice to back it up to turn it around on a very narrow runway.

Next, I tried it with a 64mm EDF and it works to brake it. I only went to 1/2 throttle for I did not want the blades to shatter since I do not have balanced blades. Braked better than I expected.

Bad features:
Smallest unit is a 40 AMP Esc, way to heavy for a light prop plane. For an EDF, they have a 60 AMP, so if you land late, might save you.

Time delay is about 1 sec after throttle is positioned at zero. That means you cover 1 second of ground travel before it reverses direction. I assume this is a safety factor added to the program and there is no way to eliminate that delay.

I was hoping to try again doing 4D maneuvers , even buying an APC reversible prop(yes, they designed a prop that either way gives a reduced and matching power).

Any questions?
 

Burnhard

Well-known member
This thread comes timely. I just bought a bunch of boat ESCs because I want to experiment with reverse thrust for breaking on our grass field. Saw a video on youtube on how to program the ranges.

The ESCs are the 40A Shark ESCs from ZTW.
 

skymaster

Elite member
I think i kind of get the idea of what you are trying to do. you could try and use a RC car ESC wich has the ability to reverse
 

Burnhard

Well-known member
I think i kind of get the idea of what you are trying to do. you could try and use a RC car ESC wich has the ability to reverse
So I bought two bi-directional ESCs for the sea duck I am currently working on. I want to do differential thrust as well as the reverse to lower the roll range when landing. I am mostly done with the wing. The ESCs are due to arrive on Saturday. Will post my experience with the programming. I am going to use a Graupner G12 receiver with a Graupner MZ24 Radio. Plan is to keep the ailerons separate and add retracts.
 

theSTOL-er

New member
Sorry for not responding

I would like to keep the esc the same and possibly look into some way of getting a programming card. A usb thing is another option but I would prefer a card instead.

I have tried to do the thing with the throttle on the transmitter but the problem is like Merv said, there is no definite brand of FT esc so I can't tell what stick positions to do because every instruction is different.

Just a funny thing, this tutor I have put a light system on with a switch so I can turn it on in the air, built a scale tailwheel system with springs and all, working on a bomb release, but I haven't maidened it yet. Keep forgetting to glue the servos in place, I take off and it essentially does a wing-over (or a stall turn, not totally sure which is which) and crashes into the ground. It is a very sturdy plane, only damage so far is a broken prop.
 

Burnhard

Well-known member
So I bought two bi-directional ESCs for the sea duck I am currently working on. I want to do differential thrust as well as the reverse to lower the roll range when landing. I am mostly done with the wing. The ESCs are due to arrive on Saturday. Will post my experience with the programming. I am going to use a Graupner G12 receiver with a Graupner MZ24 Radio. Plan is to keep the ailerons separate and add retracts.
So I did the setup and it was actually not too complicated. There were good tutorials on YouTube for setting up the differential thrust and the reverse thrust. Just two things I noted: On the combination of the differential thrust and the reverse thrust I could not use the same high correlation for the differential thrust as they show in the FT video as at lower RPM that would result in the prop spinning backwards. Its still sufficient to turn the plane on the ground. The other thing is with the reverse thrust and the prop mounting on my first try the prop unscrewed when I switched to reverse thrust. Need to make sure that this does not happen again.