IC Tricks with an Electric Airplane

[Howard Rush]

I have been flying electric stunt for awhile now, and I've finally figured out how to do some of the things we were able to do with IC engines, such as the burst of speed from running lean at the end of the flight, which is nice for the F2B one-lap landing descent from five feet.  I got a couple more tricks to work this afternoon.  For example, if you have the right settings on the electronics, you can get your motor to "come on the pipe", as Mike Haverly put it, after takeoff.  The other trick is even more bizarre, but it works, and I have a witness.

I have six-cell Thunder Power batteries, which are a funny shape.  The six cells are stacked vertically, so the battery sits tall in the plane.  The negative power lead is at the extreme bottom, outside corner of the stack.  The positive power lead is at the extreme top, outside corner.  After five and a half minutes or so of running, I can do a kill loop, just like with an IC engine.

You guys think I make this stuff up, but if you go to the Salem contest this weekend or the Madera contest later this month, I'll show you.

 


Edited to respell "cells", the misspelling of which a spell checker wouldn't have caught.

[tom brightbill]

Sounds TUTish to me.

[Steve Hines]

I seen my first kill loop on a electric last weekend. but it was on a outside and then we had to look for the battery.

Steve

[Igor Burger]

Strange, I do much better landings with electric just because it stops cleanly and does not jump up and down because of power variation at the end :- )))

... I can even manage it to stop it up wind or down wind or where ever I want ... just by proper using stopwatches  

[Keith Renecle]

Sounds to me like the battery is pulling the plug out in the loop?? Hopefully it is not flying out the bottom of the plane! I've had that before on one of my profile stunters when I did not strap up the velcro properly.........not a good idea!

Keith R

[Derek Barry]

I have been flying electric stunt for awhile now, and I've finally figured out how to do some of the things we were able to do with IC engines, such as the burst of speed from running lean at the end of the flight, which is nice for the F2B one-lap landing descent from five feet.  I got a couple more tricks to work this afternoon.  For example, if you have the right settings on the electronics, you can get your motor to "come on the pipe", as Mike Haverly put it, after takeoff.  The other trick is even more bizarre, but it works, and I have a witness.

I have six-cell Thunder Power batteries, which are a funny shape.  The six sells are stacked vertically, so the battery sits tall in the plane.  The negative power lead is at the extreme bottom, outside corner of the stack.  The positive power lead is at the extreme top, outside corner.  After five and a half minutes or so of running, I can do a kill loop, just like with an IC engine.

You guys think I make this stuff up, but if you go to the Salem contest this weekend or the Madera contest later this month, I'll show you.

 

You could just run a piped IC setup and these things would not seem so spectacular. 

Derek

[Doug Moon]

I have six-cell Thunder Power batteries, which are a funny shape.  The six sells are stacked vertically, so the battery sits tall in the plane.  The negative power lead is at the extreme bottom, outside corner of the stack.  The positive power lead is at the extreme top, outside corner.  After five and a half minutes or so of running, I can do a kill loop, just like with an IC engine.

You guys think I make this stuff up, but if you go to the Salem contest this weekend or the Madera contest later this month, I'll show you.

A hard loop shuts down your system?  Or is it the timer??  

If a hard loop shuts down the system are you sure that is a good thing......??

[Tim Wescott]

Is the balance connector rigged for uniflow?

[John Stiles]

Is the balance connector rigged for uniflow?

It happens right after the little man inside yanks out the vomit bag! 

[Howard Rush]

... I can even manage it to stop it up wind or down wind or where ever I want ... just by proper using stopwatches 

A person who can do his square eights upwind should be able to land anywhere.

[Howard Rush]

Hopefully it is not flying out the bottom of the plane! I've had that before on one of my profile stunters when I did not strap up the velcro properly.........not a good idea!

Mr. Walker's battery did that once, with a disappointing lack of fire and smoke.

[Howard Rush]

If a hard loop shuts down the system are you sure that is a good thing......??

I once wondered that with my OS .40VF after the first loop of a clover at the Nats.  So far the electric system hasn't shut down in a loop before 5:37 into the flight.  I plan to have a green light come on at 5:37.  One could probably rig a float in your fuel tank to do the same.  It could turn on a light like the low-fuel light on the Prius, which tells you when you have 15 seconds of fuel left. 

[Howard Rush]

Is the balance connector rigged for uniflow?

Mr. Igor Burger's timer takes care of the uniflow function, Tim, along with the 4-2 break. 

[Jim Kraft]

Howard; Us Old Time stunt ignition flyers need your expertise. If we could kill the battery to ignition with an inside loop it would be great. Sparkers will not die completely upon an inside loop. Or is this just more Rush trickery that won't work for anyone else. Yo best come clean on this one.

[Howard Rush]

Howard; Us Old Time stunt ignition flyers need your expertise. If we could kill the battery to ignition with an inside loop it would be great. Sparkers will not die completely upon an inside loop. Or is this just more Rush trickery that won't work for anyone else. Yo best come clean on this one.

See Tim Wescott, although a MEMS rate gyro on an ignition Old Timer seems peculiar somehow.

[Tim Wescott]

See Tim Wescott, although a MEMS rate gyro on an ignition Old Timer seems peculiar somehow.

Silicon MEMS gyros are just made out of sand and oil, ultimately.  They had sand and oil in 1952.

[Paul Walker]

Yes......

And I can do a loop kill without the TUT!

See you in Salem for the loop kill contest!

[Howard Rush]

I'm sure you can do it.
It will work terrific,
If you fly an airplane
Paleolithic.

[Jim Kraft]

Well Bummers. 
       We can't be running that modern poof in our old Sparky planes. I guess what we really need is a timer that will shut off at about 6 and 1/2 minutes. All of the old Free Flight timers that I know of only worked for like a minute or so.  That way we would not have to worry about which fuel to run or how much. Just fill it up and let her go. Guess I will have to work on that. There is a world of difference in run time between gasoline and alky fuel, and when running gasoline a click or two on the needle makes a bunch of difference.

[Doug Moon]

How does it work? I have seen and and performed some pretty insanly hard stuff with helicopters and it never shuts down.  If it did it would suck very badly and cost a ton of money...

[Tim Wescott]

We can't be running that modern poof in our old Sparky planes. I guess what we really need is a timer that will shut off at about 6 and 1/2 minutes.

I could do that for you, too, but it'd still be a modern microprocessor, even if there's no MEMs sensors.  I could do it with vacuum tubes, but you may need to build a plane that's (ehem) a bit bigger than usual.

Check with Texas Timers.  While engine timers aren't going to do it, there may be some mechanical DT timers that run that long, and you could easily rig one up to actuate an engine cutoff.

Edit:
Or use an old-style DT cord, which you could make any length.  Can you still get that stuff?

[Jim Kraft]

Thanks Tim;
  I forgot about the Texas Timers DT timers. All we have to do is break the lead to the points. Thanks again. I might come up with something that actually works. LOL

[FLOYD CARTER]

Nobody except me seems to understand Howard"s shut-off system.  Simple.  The Centrifugal force in a loop pushes the protons and neutrons to the bottom, while the electrons, being somewhat lighter, remain at the top.  since these particles cannot function without being in close proximity to one another, the battery "starves" for current (which, after all, is simply the movement of electrons).

F.C.

[Greg McCoy]

Batteries have juice in them, Howard has learned to work the juice.

[John Rist]

The real answer is that the battery is low on charge at the end of the flight.  The extra load from the loop drops the voltage below the cutoff voltage of the speed controller causing it to turn off.

PS the KR timer already does all this fancy stuff.

[Steve Fitton]

Didn't Howard's RoJett 65 do all this stuff?

[Jim Kraft]

The important thing to remember about any electronic circuitry is to not let the smoke out. It is almost impossible to put it back in.

[Doug Moon]

The real answer is that the battery is low on charge at the end of the flight.  The extra load from the loop drops the voltage below the cutoff voltage of the speed controller causing it to turn off.

PS the KR timer already does all this fancy stuff.

Will the log report show this?

I know Howard and team run their batties down around 20% before the end of the flight.  Is that correct Howard?  20% of the charge is not enough left to stay over voltage limits for one loop?  I have killed a couple of batteries along the way running them too low while pushing out flight times on my helicopter but they were still able to do the "stuff" without shutoff...  This is interesting...

[Tim Wescott]

I know Howard and team run their batties down around 20% before the end of the flight.  Is that correct Howard?  20% of the charge is not enough left to stay over voltage limits for one loop?  I have killed a couple of batteries along the way running them too low while pushing out flight times on my helicopter but they were still able to do the "stuff" without shutoff...  This is interesting...

I believe that most ESCs in helicopter mode won't shut down the motor to save the batteries.  In airplane mode that's not the case.  I'm not sure how that affects ESC settings when you're flying 'lectric, because I fly slime.

[Dane Martin]

I believe that most ESCs in helicopter mode won't shut down the motor to save the batteries.  In airplane mode that's not the case.  I'm not sure how that affects ESC settings when you're flying 'lectric, because I fly slime.

I'd have to say negative on that one. all of my heli's are set to shut off the motor at  3.2v per cell. you can adjust the shutoff and warnings to several different levels. all of the good stuff anyway. i only use castle esc's

[Igor Burger]

A person who can do his square eights upwind should be able to land anywhere.

Only in case that the circle is not built on rocky mountains grass field :-P

[John Leidle]

  This year in Muncie I did square 8s into the wind both Wednesday & Thursday.. still have to land in my favorite spot .
  John