Afraid to fly!!!!!

[schluterdude]

ok guys, just had the living crap scared out of me and i hope someone has an answer....

i went out with my 'rex 500 and vision 50 to go flying today with my wife. i took the 500 up first.

the other day i had lowered the gain to get rid of some tail wag coming out of a high-speed turn, and she was flying great! today, it's a little breezy, but managable. i went to do a loop, and as i went through it, she did a piro. i did NOT tell her to do that... same thing as i rolled. i landed, and shut her down, then turned up the gain figuring that was the problem.

then i went to the vision. i finally got her fixed after a pretty bad wreck because of a failed tail linkage. i fired her up, and as she was spooling, i was double checking tail direction, and it was fine. got her about an inch off the ground and drifted to the side. set her down, adjusted the trim, went to lift her up again, and just started piro VIOLENTLY!!!! almost like the direction was wrong, but, i know it's set up right. i go up to the bird thinking a link popped off again, but it's all there. i pick up the tail and wag her side to side, ZERO servo movement. i move the stick myself, and i have control. try shutting it down and turning it back on, same thing, no gyro. wtf!?!??!?! worked last time i flew, and worked on the bench before i went to the field.....

so i call Dan, and he tells me to go through the set-up process again, maybe i messed something up. fair enough, so i try again. the gyro sees me, as i have full control over the set-up process (it's an align 750 gyro). finish the set-up, same damn thing!!!! i tried a couple more times, and nothing, same freakin' thing, even if i try to do things intentionally wrong!!!! i do still have manual tail control though! grrrrr....

then i said screw it, put it in the car, and went back to the 500. things got REAL scary. took off, headed down the field, turned i went into a flip, same thing. crazy piro's. ok, somethings wrong here i tell myself, so i try to bring her back, and she'e going nuts. holds for a second, turns 90 degrees one way. i get her back, 180 the other. she's just going freaking nuts. if i didn't know better, i would say they were radio hits! end result with the 500 was a crash because i just had to kill the power and let her fall. i'm not kidding when i say i was afraid for my life. seriously.

i got home, and check the birds again. the gyro is working in the 500, and still not in the vision. i tried plugging different servos into each one, same results.

it would seem quite coincidental that both heli's would have tail problems. i think it's something in the Tx messing me up for some reason. i have no idea what it could be though. as i said, the 500 flew fine a couple days ago, i havn't changed a damn thing in it, other than the gain. the vision also flew fine last time, and the gyro was well away from any potential crash damage.

what do you guys think??? i am seriously afraid to fly here guys...

[ErichF]

Is there any chance that your radio has some Program mix in it related to the rudder channel? I know it sounds odd, but I have seen a radio program change at random. Did this odd behavior happen as you flipped a switch or had the collective at a particular position?


Erich

[heli-cuzz]

Sorry to hear about the crash.

I'd buy a new higher end radio. A Futaba or JR 9 channel and up will suffice.
Being afraid while flying is a bad mix. Your thumbs will do unwanted things.
I know easier said than done, but try and relax while you're flying even when things go wrong.

[schluterdude]

i was already planning on a radio upgrade, just wasn't sure when/what...

cuzz, thank's for the advice. i was fine until after the 500 dumped and that was the end of my day... i meant it to mean i am afraid to fly with this current situation. until it gets resolved, there is no way they are going back up. that's why i put this under the safety thread. i thought this could be a considered a safety issue...

[ErichF]

i was already planning on a radio upgrade, just wasn't sure when/what...

cuzz, thank's for the advice. i was fine until after the 500 dumped and that was the end of my day... i meant it to mean i am afraid to fly with this current situation. until it gets resolved, there is no way they are going back up. that's why i put this under the safety thread. i thought this could be a considered a safety issue...


Having re-read you first post, I'm inclined to say you might have fudged something as you changed the gains on the gyros. That would be hard to do on both models, though.

Another thing you can do is play with the rudder stick and see if you can induce a failure on the ground. It could be a dirty or failing rudder potentiometer in the transmitter. When testing it, just move the stick as you would in flight...light, gentle movements in realistic ranges. Grabbing the stick and yanking side to side might be moving the pot outside it's bad range, giving you a false sense that all is OK.

If you happen to have a servo/RX tester that can display the PWM output of your RX or gyro, plug that in and check the outputs while doing this test. The output should be smooth and consistent with stick input. Jumping numbers indicate a bad pot.

Erich

[schluterdude]

dan and i considered the pots, especially considering the dx6i, and the recall they had on them. i checked my date code, and it wasn't one of the affected models. i also checked out the "monitor" screen in the set-up menu, and all was well. slow movements or fast movements, goes right back where it's supposed to, and no dead spots.

i don't remember if i mentioned which gyros were in which bird, the 500 has a 401, and the vision has a 750. i checked the gains on both, and they were both o.k.

here's another question on the 750, because i never paid that much attention to the start-up. the lights on it would set off an epileptic seisure if you looked at it, and it lasts about 2-3 seconds. do they all do that, or is that one of those deals where that's a factory set-up mode telling you it's ready for software or something like that???

tonight i'm going to take both gyro's out and switch them between birds to see if that makes any difference. although, i know my TX is talking to both of them...

[mkoutnik]

Are you sure the tail rotor is spinning counter-clock-wise when the main rotor spins clock-wise...My 401 was doing to same thing you described, and I discovered the tail rotor was spinning in the wrong direction (twisted tail belt)...

[schluterdude]

on my 500, there's a torque tube, so it has to (and is) spinning the right direction...

i thought that may have been the problem on my vision, but, rotation is fine, and there's no output from the gyro...

[vermonster]

my 2 cents, I would say you have a problem with the transmitter. Being two different gyros from two different manufactures. I highly doubt both gyros are screwed up. The transmitter is the common denominator here.

[schluterdude]

i'm leaning towards the Tx as well....

but, an update. i took the 750 gyro out of the vision and plugged it into the 500. still no response from it...

is it possible that the Tx for some reason is just sending out an intermittant 50% resulting in zero gain on both of them? could the 750 just be more suseptable to this than the 401?

[vermonster]

Set the percentage above 50%, like 60. Make sure your switch is in the correct position (heading hold). Then re bind the receiver to the transmitter. The resolution is not exactly at 50% on all radios (ie it could be 51 on yours). See if this helps. :confused:

[kcgraves]

Set the percentage above 50%, like 60. Make sure your switch is in the correct position (heading hold). Then re bind the receiver to the transmitter. The resolution is not exactly at 50% on all radios (ie it could be 51 on yours). See if this helps. :confused:

Aren't you suppose to be at your Daughter's Wedding?

[vermonster]

Aren't you suppose to be at your Daughter's Wedding?

I'm here, do realize how long it takes for the girls to get ready. :D Pictures in an hour, then the big event. :D I brought the laptop

[kcgraves]

I'm here, do realize how long it takes for the girls to get ready.

That is a rhetorical question if I ever heard one.

Good luck and have a great time. Congratulations.

[schluterdude]

whoa, forgot your daughter was getting married! congrats man! tell her that all of us here wish her and her new hubby the best, and have a few drinks for all of us here, you earned them!

i have my gain set at about 75% for hover, and around 68% for idle up. what i meant about my previous post was perhaps my Tx was sending out the intermittent 50, not that i was sending it....

tmw i'm going to head to the hobby shop gyros in hand and see if they can plug them into one of the birds they're repairing and see what happens....

[schluterdude]

ok, so i think that the gyro (750) in the vision is just bad, plain and simple. so, need a gyro for her.

the 500 is still freaking me out though. i was just trying to get her to repeat what she did (on the bench since she needs repairs), as far as loosing the tail. i was moving the sticks like was trying to do a roll/flip/loop, and nothing, the tail servo just stayed there. then i tried "flipping" her in the air, and again, the servo just stays there, except for me twisting the bird around. the tail does what it's supposed to when i twist it side to side, along with slowly bring it out and then snap it back in. nothing weird at all. this is really freaking me out!!!

so do you guys think the odds were just against me and i had BOTH a gyro and some sort of Tx/signal failure at the same time????

[schluterdude]

issue resolved!!!!!!

this morning i took the 401 out of the 'rex, and put it in the vision, and she's alive!!!!

so, here's what dan and i came up with... the 500 must have had some sort of high frequency noise coming from something inside (when i rebuild her, i'll look for it), and it just ticked the gyro off causing the weird reactions. the 750 just crapped out, plain and simple. i also think that may have been what caused the wreck i had, rather than the linkage falling apart. i assumed it was the linkage, because it was busted when i walked up to her, and it had piro'ed uncontrollably in the air. i'm betting it was the gyro at this point.

also, a tip if anyone wants to use an align 620 servo with a 401 gyro. run the gyro in "regular" servo mode, not digital. if you do, every time you fire it up, the servo will bang lock to lock. it has something to do with framerates, and even though the 620 is capable, it or the gyro doesn't like something, and bangs around in a sort of referance mode. this will cause the servo to burn out! run in normal, and you're good to go.

[vermonster]

Thanx for all the congatulations! Just got back to Vermont. Glad to here Schluterdude you got the mess straightened out. I've read somwhere about the switch on the gyro changing the frame rate. Maybe Chuck could chime in.;)

[gouki74]

the gp750 doesn't seem to be of good quality :( a fellow flier has had his 450pro for about a month and his 450sport for two weeks and both the gp750s needs replacing already :(

[blax1]

Well if they are both fixed..................GOOD

Remember this, I haven't read it all, it may or may not be relevant.

http://www.spektrumrc.com/Articles/Article.aspx?ArticleID=1901

[schluterdude]

yup, that was the first thing i checked (the recall). mine wasn't one of the affected units, but i peeled her open anyway to make sure that wasn't the problem...

the switch on the gyro does affect the frame rates the gyro sends out. the "DS" mode on it, of course has a higher frame rate. and the 610 is supposed to be able to support it, but, for some reason they don't talk right during the start up, causing it to bang around like that. i saw posts on other forums with people having the same problem.