View Full Version : Good Glitch ?

05-12-2008, 03:42 AM
Hello All .. I had a "Glitch" the other day but I'm happy about it because at least I was flying long enough for something like this to happen .:D..

Usually I crash within the first few seconds .. I had a good day with my Slow Stick very light wind ... Got the plane going OK I was keeping it flying but with some mistakes .. Thank god for the Slow Stick and it's forgiving flying character ...

Anyhow The plane was maybe 75 yards away , been in the air for around ten minnutes tops and I could see the prop had quit turning ... I was not that far off the ground so I could not tell if the rudder and elevon had quit to..It "Landed" pretty fast .. When I walked up to get the plane every thing was working again ..

So I flew it again and it did the same thing but a little sooner and closer about 50 yards and when I got to it the plane was working fine again .. So I put that one away and got the Super Cub out ..

Any how can anyone give me a clue what to check???Please:D .. I am thinking the receiver or the ESC Both of which should be good ones .. Is there any way to test these other than replacing them ?? Just thought I could run the plane on the bench and see what happens ... I did do a "Range Check " on the plane after the first glitch but it worked fine then ..

Any help I can get will be really appreciated .. I fineally get to where I can fly a little and the electronics go wackey :{.. Thank You for Looking at this ... Don J..

05-12-2008, 04:42 AM
The first thing that comes to mind is that the battery was not fully charged and the ESC was shutting down due to low voltage. Usually, after it sits a bit, it will power up again for a bit, then shut down again.

I would recharge the battery and see if it does it again.

05-12-2008, 06:35 AM
Don, what equipment are you using...Receiver, battery ESC....?

05-12-2008, 08:39 AM
Hi Don :) it sounds like 10 mins is to long to fly on your lipo, and it went into LVC , Low Voltage Cut off, only fly for 6 to 8 mins, in LVC the motor will stop working, because the battery voltage is to low, but the servos will keep on working to get the plane back in, dont try to take off again after a LVC or you will crash your plane or ruin your lipo or both, A HINT when your flying and it goes into LVC, TURN of the throttle for a second, then go to half throttle, the motor should come back on, just enough to get you back in, if your far out, Hope that helps, Chellie

05-12-2008, 05:12 PM
WOW .... Thanks for all of the replies .. I appreciate it .. Let's see ... the battery --is a WOW from Jeff at Headsuprc.com and is a 3 cell 2250mah 20C I recharge it almost every time I go unless the last time I crashed after 10 seconds or so .. Then I might skip the recharge ..

The rest of the electrics - Motor 2409 tower pro .. ESC Tower Pro 30 amp from Heads up RC

And the Receiver ... My Main Suspect is a "Dynam" someone suggested this on to me as a good/OK one for a low priced receiver .. When I got it I found out that you were supposto use only their Crystals and they did not make my channel 25 one ... I tried a crystal out of another receiver that was broken (a corona) and it worked .. Or seemed to ..

I don't know for sure but I will try changing that first .. Sorta don't think the battery is the problem but who knows .. Someone should invent a "Load Tester" for RC Batteries like they use on automotive batteries ....

Thanks again for all of the help .. I'm just really happy that I could keep the plane in the air for 10 minnutes or so ....

05-12-2008, 06:01 PM

I think you hit low voltage cutoff. 10 minutes is a typical flight ... especially if you're not sure if you had fully charged your battery.

The behavior of Low Voltage Cut Off (LVCO) varies from one ESC to the next ... but in general, it kills power to the motor while leaving power available to the RX and servos so you still have control.

Many ESC's will restore power to the motor for a very short time after bringing the throttle back down to 0 for a second or two to enable you just a little bit of power to set up for your landing.

Some other ESC's have what they call a 'soft' cutoff. These ESC's gradually reduce the power to the motor and then finally cut it off. These often will allow a 'reset' for a short burst of power as well.

05-13-2008, 05:15 AM
Hello Gnascher,

Do you really think I ran the battery down ?? Did you see where the battery is a 2250 mah size one ?? Or are you you thinking I didn't charge it ?? Guess thats possible .. I sorta think the receiver is the culprit .. Gonna try to switch it out ..

Trouble is the one I was gonna use (A Berg) I broke the antenna wire removing it from the old model ... It had CA Glue and tape on it in several places and just broke taking it out .. Do You know if this can be fixed ?? And how I might try??

Thanks for the reply .. Don J .

05-13-2008, 08:13 AM

Without knowing for sure if you maintained attitude control after the motor quit, I can't say for certain that it is LVCO, but that is what it sounds like to me. 2250 is a lot of juice, but if it wasn't fully charged ... who knows.

As for your broken antenna, if there is still some antenna wire sticking out, you can solder on a new length of antenna wire. However, you need to make sure you make it the same length as the original ... length is a critical factor for an antenna wire. If you do this, put some heat-shrink tubing over the joint, and range-check carefully before flying.

05-14-2008, 11:28 PM
Thanks again Gnash :), I have replaced the antenna and changed the receiver .. Waiting for the wind to slow now .. Guess I can Range test it thou even with the wind up ..

How far away should I go with the antenna down on my transmitter to test if the receiver works ?:ws:? That is how you do it .... Right .. Thanks again .. Don J.

05-14-2008, 11:31 PM
Yes, the "standard" range check is to keep the antenna down and check that you have control of all channels from 30 feet away.

However, since the setup you have is 'suspect', I'd add an additional challenge backing up as far as you have room for, and see when (if) you begin to lose contact.

Then, decide for yourself if you feel confident with the setup.