I can not be 100% sure of that, for the ones that failed actually in my aircraft. I switched on and went through my normal pre-flight - checked the voltage on the built-in DVM, etc then went to check all control surface movements before start-up. When I got to the rudder check, I looked over at the rudders at the same time as I gave left rudder input.... and noticed then that they were stuck hard-over. So, I have no way of knowing whether the rudder went hard over as I switched on, or only when I fed it some input.

One of my buddies who was helping me suggested that the gyro could have been confused about its neutral if I had perhaps inadvertantly bumped the aircraft during power-on. I tried cycling the RX battery switch, but the servos did not move.

Then I switched off, manually moved the servos back to neutral, and switched the RX on again. Both servos stayed in the neutral position, rather than going back to the hard-over position they had been in previously, but they stayed neutral regardless of the input from the TX. They also did not attempt to stay neutral when some manual pressure was applied to deflect the servos - in other words after the initial hard-over kick, the servos did not move at all under their own power. However, a later test showed one servo once again moving some of the time, and then it stopped altogether again.

I think that this is a serious enough issue that JR would need to find the cause for failure and report it immediately if it is a production problem!

While it certainly was disconcerting for me (and probably David too), I would caution against over-reaction. So far, *two* JR customers have reported experiencing a similar symptom (not necessarily identical cause). That's two out of who knows how many customers.

Before I got into the software business, I used to work as an electronics test & repair technician for a British defence company. I can tell you that sometimes a series of unconnected failures can look like a pattern, without actually being one, especially when the sample space is small enough.

What I'm trying to say is that while I would hope that JR will take the time to look at the returned servos in a little more detail than they would do if the servos were sent in for e.g. crash damage, I don't think we should necessarily assume the worst... let's wait & see what Horizon has to say, and wait to see if any more people report having the same kind of problems. In the meantime, lets not panic. ;-)

Regards,
Gordon


P.S. Regarding the simultaneous failure - yes, that does suggest the possibility that the trigger, if not the actual problem, could in some way be external - anything from the battery to the gyro could have a hand in this.... but there again, the ones that failed on the bench (as I tested them before installing them as replacements for the ones that failed in the aircraft) were not connected to the same battery, had no gyro attached etc. So, speculation is probably pointless, and I'll await Horizon's response.