A West Coast flier with a tri-motor airplane, powered by one battery , three Lite ICE ESCs and throttled by one FM-9 timer, found that all three ESCs would blip the motor after the start button was pushed but only two motors would start up and run during the flight time. A replacement ESC behaved the same way. A similar experience was reported recently on the East Coast. In both cases, the motors would run if the throttle/RPM setting was advanced from a very low initial value.

The first “High RPM” range for the Castle Creations’ Phoenix ESCs extended from 1.1 to 1.9 ms pulse widths (corresponding to throttle values of 10% to 90% of the nominal throttle range). Later they changed the helicopter governed range to 1.2 to 1.9 ms (20% to 90%), with the new 1.1 to 1.2 ms range reserved for autorotations – and the CL High RPM followed along.

The current FM-9’s “Phoenix new High” is an RPM vs. throttle calibration for this latest CC High RPM mode. It allows the user to program an RPM as low as 7,300 RPM, which corresponds to 1.2 ms (20% throttle). Users should therefore be aware that their motor may or may not start up and run at low RPMs at or close to 7,300 RPM, even though the motor will blip as expected.

I apologize for being so slow in getting back to you, Dean.

I did make some measurements this evening, using an ICE LITE 50 ESC powering an E-Flite 25.

Start power at Medium (59): Throttle 20% (1.2 ms), RPM 7300: motor blipped but did not run, with either a 3S or a 5S battery.

Start power at Low (39): same results

Increased throttle to 25% (7740 RPM): motor blipped and ran with both batteries.