For the upcoming competition season Chris Cox and I built new Bob Hunt Crossfires.  These are the 4th edition for both of us and since the first ones built for the 2012 season we've made some modifications to Bob's original design.  The 2015 version was dubbed the Mk III Crossfire XL and has gone through the most changes with a straight flap hinge line, 30 sq. in. increase in wing area (to accommodate heavier batteries, 6S vs. 5S), longer tail moment, and a decrease in stab/elev. aspect ratio.  All the changes have proven to be beneficial to performance.  We also installed Igor Burger's active timer motor controls.
After getting the ship fairly well trimmed without the active controls turned on, I slowly started to add regulation to the power system.  I quickly discovered that my sensing unit needed to be moved rearward from the point I had originally picked which was just aft of the CG.  Regulation was now starting to become apparent but for some reason mine seems slightly amiss. The regulation while slight at the time, seemed backward.  I talked to Mr. Walker and we went over settings and he made some suggestions.  Further flight testing and slightly increasing the boost showed little improvement.  Chris was starting to add some regulation to his ship now that he had the trim somewhat figured out and all was going well.  His regulated as it should and he was slowly working toward a higher value.  I was out flying by myself last week and increased the regulation even more and pretty much convinced myself that the unit was working backward.  I called Paul again after driving home from the field and pondering the problem.  My first question to him was "do you think that flying clockwise as I do, cause a problem with the sensing unit in Igor's system?".  He said that he wasn't sure how the units were programmed but didn't think it would make any difference.  He did say that my thoughts might have some merit.  I emailed Igor and ask him about the problem thinking maybe I got a unit that had gyros with the incorrect polarity or something.  I told him that I was thinking about putting the unit in upside down.  He answered back quickly with lots of smiley faces saying that yes, I had to install the unit upside down due to my clockwise flight operation.  He said his model would do the exact same thing if he took off, did a half loop and then did a backward pattern, starting from inverted flight.  Reinstalling the unit upside down, and now it performs perfectly.  So for all the hundreds of clockwise flyers out there, disregard Igor's instructions and put the sensor in upside down. :-)))))     

If it uses more than one sensor then you need to turn it upside down the correct way.  Wires front just like "regular" (if I remember Igor's pictures correctly -- believe Igor if he says different) and whichever face points out on an ordinary rotation plane should point out on a weirdo reverse direction plane (we should give you negative points for going backwards, Alan -- you could be the first control line stunt pilot to break -590).

If it just uses the accelerometer, then just make the "out" side face out.  If Igor wanted to go to the (probably considerable) trouble, he could stick a big arrow on each one and the directions could just say "make it point out".

He answered back quickly with lots of smiley faces saying that yes, I had to install the unit upside down due to my clockwise flight operation.  He said his model would do the exact same thing if he took off, did a half loop and then did a backward pattern, starting from inverted flight.  Reinstalling the unit upside down, and now it performs perfectly.  So for all the hundreds of clockwise flyers out there, disregard Igor's instructions and put the sensor in upside down. :-)))))      

You need to rotate the sensor package 180 degrees about the X (fuselage) axis from the orientation normal people use.  That makes the Y-axis (spanwise) sensor point in the correct direction relative to the center of the circle.  If you merely turn a normal airplane upside down, the orientation of the Y-axis sensor relative to the center of the circle doesn't change.  Likewise, if there is a Z-axis angular rate sensor (gyro) in Igor's package, you'd need to rotate the package 180 degrees about the X axis to get it to work correctly in your airplane.  A normal airplane will rotate to the left relative to the Z (up-and-down) axis in either upright or inverted flight; yours will rotate to the right.

If the wires from the sensor are in the front, an X-axis sensor will point in the correct direction for either a clockwise or counterclockwise airplane.  

(written before Igor's and Tim's posts, but posted anyhow)

well I needed 4 years of development just to find out WHAT TO CONTROL at all ... the rest was easy, little mathmat, little physics, little programming etc ... so answer is yes, it can control quadcopter with some change in sofware ... if someone is able to say WHAT it really has to do :- ))))))))))))))))

Tim, I think you need to follow the example of the Jive Combat Team.  We use our Powers only to do good.

Tim,,, Tim ,, Tim,,
that will NOT get you another write up in Stunt news,,