Beachcombers Throttle Wierdness

Beach and I went flying this afternoon. When he was on the helipad ready to take off he flipped off his throttle hold,on his DX6i, his 450 started spinning up! His throttle stick was all the way down. When he flipped throttle hold back on it spooled down. Hold back off, and it spooled up again. We then reduced the throttle trim and were able to get the rotors to stop spinning when we got about 1/2 way down the adjustment of the throttle trim.

It apears like the transmitter throttle output isn't calibrated to the ESC throttle, all of a sudden. I know with my Castle Creations ICE 75 ESC I had to teach it the transmitter throttle range. I don't remember having to do that with the basic ESC's that he and I run on our 450s. I'm not sure the brand of ESC that he is running but, he uses one of the Credit Card programing cards to set the ESC up. I just talked to him on the phone and he checked the ESC with the programming card and it appears to be setup correctly. No governer mode enabled etc.

His headspeed is also apparently full steam ahead also, it sounds really fast. It seems like the throttle range of the transmitter has changed or something. Like the delta of the throttle has changed and the range has shifted up.

He is able to fly but, something has changed.

Any Ideas Anyone? We are scratching our heads.

Apparently when he plugged his battery into the ESC his transmitter throttle stick wasn't at the low position. This caused the ESC to go into programming mode and reset his ESC's throttle range. He had used the programming card to program his ESC and he didn't know about programming the ESC with the transmitter sticks.

I guess we should always set the transmitter throttle range for the ESC with the transmitter stick programing even if we use the programming card to program the ESC. And also be aware that it is possible to inadvertently reprogram the ESC if you power on the ESC with the transmitter sticks not in their normal (0) positions.

It had us scratching our heads for a while! But, we got it!

Thanks, Curt.

For the benefit of anyone else reading this thread with similar problems; here a little more info.

I have a Turnigy Sentry 40 A speed control. It has worked flawlessly for at least a dozen flights. Meanwhile I have been adjusting my throttle curves on my DX6i to fine tune everything. So today, as Curt described, I apparently entered the speed control program mode from my transmitter, without realizing it. Beware!

If you turn on your transmitter first (a habit from my 72 MHz days), then plug in your heli with throttle stick above zero (oops), your speed control will CHANGE your throttle range in the speed control. Only after coming home and reading the instruction for the speed control, did I see how to re-do my throttle range in the speed control, from the transmitter. This in NOT a function available from the speed control programming card. Before that I thought the problem was in the transmitter, so I did all sorts of unnecessary stuff (re-bind radio, copy model and reset, ugh).

By-the-way, the symptoms of a re-programmed throttle range is full (or seems like it) throttle ALL the time, sorta like idle-up 100%. It actually flew ok, but head speed was screaming compared to what I was used to. Live and learn. Sort of like landing in idle-up, except my pitch curves don't have that much negative trim.