see_e_oh
07-31-2010, 11:01 PM
I'm a heli newbie, so it's probably, me; but I can use some help.
I keep loosing control of the rudder gyro on my 550E. And I'm stumped ... and frustrated. Sorry for the lengthy post, but I wanted to provide enough information to be useful.
I had about 8 flights - (I've had 10 hours of flight training on an 880mm Mongoose gas heli). I'm just learning to hover this electric and experienced a small amount of "tail" wag, but otherwise showed solid gyro/rudder and other flight controls. I'm running the heli stock with a JR 9303 transmitter using the Gyro Sens (Aux2) with Gyro gain set at 62. I upgraded to v2.1 and ran through the 3G set up again. No noticeable change in wag and no change in gyro gain indicated. I had a hard time pulling out the 3G cable from the sensor and control units, and pulled the yellow lead out at one end. I've repaired many servo connectors, so this was no problem, but I bought a replacement set of cables anyway. [Subsequently I learned the trick of pushing down against the connector to release it from the white clip and then easily pull out.]
I had an expert flyer test fly the heli after the upgrade and all was well (same little tail wag). On my first flight, I drifted left a bit on lift off and ran the tail through some small weeds near the landing pad which chewed up the tail rotor blades and about 5 teeth on the forward gear. I replaced tail rotor blades, forward gear and the repaired 3G connector cable. Before putting it up myself, I brought my 550E to an expert flyer/heli mechanic at my LHS. He verified the 3G operating. As soon as it broke ground, the tail went into an uncontrollable pirouette. We rechecked all the mechanics, including pulling the main shaft and making certain the one-way clutch was working properly. Re initialized the 3G system .... test flew again .... same problem.
Took it to another buddy, actually the guy who built the kit for me, who is also an expert flyer and mechanic and verified all the mechanics were correct. Confirmed the 3G was working properly. Same pirouette problem when he lifted off. Then we removed the NEW 3G cable and replaced it with the OLD repaired cable and PROBLEM SOLVED. Rudder held nicely. We ran the GUI, and as suggested in a number of places to fix the tail wag problem, reduced the "rudder lock gain" to 50 from 70. Flew again, increased the Gyro gain to 70, Gyro held nicely, although it did a bit of hunting at the stop point/rudder change of direction.
OK, so then today, first chance to fly after the 3G cable fix, I confirmed the 3G settings were all working, then I took it out. First flight no problem other than the end of travel rudder hunting referred to earlier. Turned the AIL gain to 11 o'clock. Took another flight and didn't notice much difference, but the tail wag bothered me, so I loaded up the GUI, turned up the rudder lock gain up to 60 (from 50 but still down from the default 70). Left the Gyro gain on the transmitter at 70. At worse I expected there would be some rapid tail wag if gain too high. AIL control setting still at 11 o'clock on the 3G control unit. Lifted off and as soon as it broke ground, the tail went into an uncontrollable pirouette, had a tail strike and tipped over.
Replaced the main blades, tail rotor blades and front gear again. Loaded up the GUI, returned the Rudder Lock Hold back to the 70 default, and returned the AIL control unit setting to 12 o'clock and returned the Gyro gain to 62 (everything exactly where it was during the initial successful flights). Let my expert builder/flyer buddy confirm that the AIL/PITCH/ELE/RUDDER 3G were all working properly. He took it up slowly and, sure enough, uncontrollable pirouette problem still. He brought it down safely. Checked the 3G control over the rudder with the power on and it didn't move... tail lost again. (the tail rotor blade pitch responded to stick control, but not the 3G).
So, I've concluded this is not a mechanical or really a 3G cable problem, but rather some problem with the 3G Sensor or Control units.
BTW, I have read the threads in the Align FBL forum about the connector problem. I have verified that the white holding clip is fully engaged in the housing on both the sensor and control units, that all pins have sufficient space to plug into the female connector on the 3G cable. It appears that all pins are making contact.
Again, I'm a Heli newbie (although seasoned IMAC flyer), so this is all new territory for me.
I'll certainly call Align on Monday, but in the meantime I've ordered a replacement FL760 from Taiwan.
Anyone got any ideas?
Thanks in advance!
I keep loosing control of the rudder gyro on my 550E. And I'm stumped ... and frustrated. Sorry for the lengthy post, but I wanted to provide enough information to be useful.
I had about 8 flights - (I've had 10 hours of flight training on an 880mm Mongoose gas heli). I'm just learning to hover this electric and experienced a small amount of "tail" wag, but otherwise showed solid gyro/rudder and other flight controls. I'm running the heli stock with a JR 9303 transmitter using the Gyro Sens (Aux2) with Gyro gain set at 62. I upgraded to v2.1 and ran through the 3G set up again. No noticeable change in wag and no change in gyro gain indicated. I had a hard time pulling out the 3G cable from the sensor and control units, and pulled the yellow lead out at one end. I've repaired many servo connectors, so this was no problem, but I bought a replacement set of cables anyway. [Subsequently I learned the trick of pushing down against the connector to release it from the white clip and then easily pull out.]
I had an expert flyer test fly the heli after the upgrade and all was well (same little tail wag). On my first flight, I drifted left a bit on lift off and ran the tail through some small weeds near the landing pad which chewed up the tail rotor blades and about 5 teeth on the forward gear. I replaced tail rotor blades, forward gear and the repaired 3G connector cable. Before putting it up myself, I brought my 550E to an expert flyer/heli mechanic at my LHS. He verified the 3G operating. As soon as it broke ground, the tail went into an uncontrollable pirouette. We rechecked all the mechanics, including pulling the main shaft and making certain the one-way clutch was working properly. Re initialized the 3G system .... test flew again .... same problem.
Took it to another buddy, actually the guy who built the kit for me, who is also an expert flyer and mechanic and verified all the mechanics were correct. Confirmed the 3G was working properly. Same pirouette problem when he lifted off. Then we removed the NEW 3G cable and replaced it with the OLD repaired cable and PROBLEM SOLVED. Rudder held nicely. We ran the GUI, and as suggested in a number of places to fix the tail wag problem, reduced the "rudder lock gain" to 50 from 70. Flew again, increased the Gyro gain to 70, Gyro held nicely, although it did a bit of hunting at the stop point/rudder change of direction.
OK, so then today, first chance to fly after the 3G cable fix, I confirmed the 3G settings were all working, then I took it out. First flight no problem other than the end of travel rudder hunting referred to earlier. Turned the AIL gain to 11 o'clock. Took another flight and didn't notice much difference, but the tail wag bothered me, so I loaded up the GUI, turned up the rudder lock gain up to 60 (from 50 but still down from the default 70). Left the Gyro gain on the transmitter at 70. At worse I expected there would be some rapid tail wag if gain too high. AIL control setting still at 11 o'clock on the 3G control unit. Lifted off and as soon as it broke ground, the tail went into an uncontrollable pirouette, had a tail strike and tipped over.
Replaced the main blades, tail rotor blades and front gear again. Loaded up the GUI, returned the Rudder Lock Hold back to the 70 default, and returned the AIL control unit setting to 12 o'clock and returned the Gyro gain to 62 (everything exactly where it was during the initial successful flights). Let my expert builder/flyer buddy confirm that the AIL/PITCH/ELE/RUDDER 3G were all working properly. He took it up slowly and, sure enough, uncontrollable pirouette problem still. He brought it down safely. Checked the 3G control over the rudder with the power on and it didn't move... tail lost again. (the tail rotor blade pitch responded to stick control, but not the 3G).
So, I've concluded this is not a mechanical or really a 3G cable problem, but rather some problem with the 3G Sensor or Control units.
BTW, I have read the threads in the Align FBL forum about the connector problem. I have verified that the white holding clip is fully engaged in the housing on both the sensor and control units, that all pins have sufficient space to plug into the female connector on the 3G cable. It appears that all pins are making contact.
Again, I'm a Heli newbie (although seasoned IMAC flyer), so this is all new territory for me.
I'll certainly call Align on Monday, but in the meantime I've ordered a replacement FL760 from Taiwan.
Anyone got any ideas?
Thanks in advance!