Well guys, at the risk of being beat up, I'll offer my FACTUAL experiences with my ex-BobCat and my OPINION of what I think happened in my particular instance. I built a BC XL exactly per instructions except for adding flaps/ailerons per John Redman's recommendations, and powered it with a P120. I was very careful to follow BVM's instructions EXACTLY for all the building and control set ups. I had around 40 or so flights (great flying machine, BTW), but I experienced elevator mushiness on occasion, (not on loops as I always reduced the power on the backside of the loop) but on normal 90 degree bank fast pitchouts which acted like I had 1/2 or less normal throw (pitch only). It ONLY happened after a fast pass with a level 90 degree bank pull out. Reducing throttle (and speed) during the sluggish pull out allowed the BC to come on around with restored elevator authority as the speed bled off. This was a random happening, however, and always scared the p*** out of me when it happened, because it wasn't consistent, and I wasn't prepared for the lowering of the elevator authority when it did happen every time. I checked everything over many times, but couldn't duplicate the condition consistently. It was a random happening, so as a last resort, I changed the 3301's out for 9411's on the elevator and made new servo covers (which protruded into the slip stream with NO adverse effect). On the very next flight with the new servos, about 5 minutes into a normal 8 minute flight, as I was doing a 1/2 throttle low pass, the radio went into failsafe as I asked for elevator to stop the descent. The BC impacted the runway directly in front of me at about a 15 degree descent angle, wings level. The engine got it, the gear was retracted and survived, the radio and tanks were OK, but the airframe was destroyed.

I sent the 955 receiver, 10X transmitter, receiver battery pack (1800 mah, 4 cell 4.8v) and the 9411 servos to JR for a complete analysis. The only thing JR found was a kink (break of most wires) in the RX antenna about 3" from the case and had to replace the gears in both 9411's. It is unknown if the kink/break happened prior to, or during the crash. Not all the wires were cut, so JR felt that the radio probably hadn't gone into failsafe from the kink since it happened at a very short distance from the transmitter (but it WAS possible). I (and my other jet buddies here) suspect that since I had used standard servo extension wires (not heavy duty), that the 9411's may have lowered the voltage which caused the RX to go into failsafe. As everyone knows, the elevator servos are a LONG way from the RX and battery pack. The 3301's may have not had enough voltage to work against the speed either, but since it wasn't consistent, there's no way to really know for sure. If heavy duty wires were required in the 3301 set up, I would expect that fact to be in the instructions issued by BVM. Maybe it's just good practice to always do that, but I didn't know at the time and my other modeling activities didn't require heavy duty leads. In any event, I'll sure use heavy duty in all my new installations, just to be sure. In my opinion, the best way to determine if the recommended 3301's are adequate for the task, is to do a wind tunnel analysis as suggested by David G. In the meantime, as also suggested by David G. (and others), just change the servos to larger ones, and make sure to use heavy duty wiring if there is doubt. After I made the change to larger servos, my BC had been flying with no problems during the ill-fated flight until the lockout (cause unknown). Unfortunately, at this point, everything is pure speculation as to the exact cause of the crash and RX entry into failsafe. I DO know that during the flight I had NO elevator mushiness occur with the 9411's, and I SPECIFICALLY, DELIBERATELY tried to induce the condition with no luck, so I suspect the 3301's were not up to the task demanded of them - it may be the small gauge servo extensions I used, but the 9411's worked fine until the RX went into failsafe. Everything was checked out, and there was no smoking gun that we could find. In any event I have since changed to large gauge extensions (heavy duty gold connectors), and am using a 5 cell AT LEAST 1800 mah RX battery pack.

I am currently flying a EuroSport hard with 8411's on the rudder/canards, and on the elevons with NO problems - and am very happy with my new bird. So far, I haven't experienced any control problems with my new set up in the EuroSport.

Regards, Les