Tail 'kick', hiccup..... [Archive]

View Full Version : Tail 'kick', hiccup.....

skydude

03-16-2008, 03:49 PM

Whilst I am spooling up everything is fine. I always lift off slowly to about 3-4 feet.

Within 30 seconds of holding this checkout hover it will 'kick' in yaw - tail to the left - a few inches and make a hiccup in the power noise. I have held the hover for a minute or two to see what happens, get bored and start flying. It will never do it again until the next new packs are in and then repeats exact same thing. And then flies fine. Every time.

The first time it did it I tightened the belt. It seems plenty tight now. And it is the strangest thing that it flies sweet for must be at least 8 minutes.

Equip: Tonic z30, Hobby Wing 60 opto esc, Hobby Wing 7.5 bec, Futaba r607fs rx commanded by the 6 channel tx, Flightpower 3200 evo 30c's, futaba s3151's on main shaft, 9254 on tail, g401.

Anybody ever experience this. Seems different than the 'tail wag'.

Call me - Hates glitches and *****es.

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mysticmead

03-16-2008, 06:54 PM

my little 450 was doing something similar.. the motor would glitch.. but only on the second pack.. I re-routed my antenna wire so it was no longer coiled and it hasn't done it since.. but when it happened, the motor would drop rpm and back to where it was in a few mili seconds. if something like that is happening to you and your belt is real tight it'll kick the tail. just like if you hit throttle hold the tail will kick.

skydude

03-16-2008, 07:45 PM

I have never had anything close to this with over 800 flignhts on the 450 rex's with the faast system. Doesn't seem like radio glitch because it only happens the one time. Seems a radio glitch would pop up sometime during flying.

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mysticmead

03-16-2008, 08:36 PM

could it be a ESC problem?? maybe a solder joint that expands once it gets warmed and make a good connection.. intermittent problems like this are the hardest to troubleshoot.. I get to do it daily with servers....

skydude

03-17-2008, 12:02 AM

Wazzer

03-17-2008, 02:27 AM

Are you running the Thrusted tail blade grips?

Finless described the same problem being caused by the tail blades grips binding all be it at high head speeds.

Might be worth a look.

I have installed raptor tail hub bearings and grips on JB's Hurry. No thrust races but they they fit a treat and give much better suport to the twin radial bearinsg than the standard hurry hub does.

Ben

skydude

03-17-2008, 08:11 PM

Seems like blade gripping issues would pop up randomly during flight? If it is not too much trouble which post is it you are referring to. Still have to get the wife out to tach my head. (What did I just say?)

This is starting to really bug me. Did it on the first pack today. Right after hitting nominal hs. Not again for the whole flight -- maybe 8 minutes. And did NOT do if for the second pack, which it usually does.

I hate glitches and *****es.

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Wazzer

03-17-2008, 10:02 PM

I think Finless coverd it in one of his later videos about the Hurricane

Take a look here for the Tail Fix video it is at the top of the list of videos
http://www.helifreak.com/showthread.php?t=31211

But like you pointed out your problem is intermitent so not sure how useful it will be.

but worth a look!

Ben

skydude

03-17-2008, 11:44 PM

That does SOUND just like my problem. The way he says tail 'kicks' and the way he describes it. He does not state what the frequency of the kicking is when this problem manifests itself.

Will try to get the wife to tach my head (???) and see what it is anyway. That would be strange if I had 2300 and it was what was causing the 'kick'.

Thanks for pointing that out to me Mr. Wazzer. I will leave no nut unturned.

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bpd964

03-18-2008, 08:33 AM

Re-bind your RX / TX..

Jungle Bob

03-18-2008, 09:25 AM

Is it possible that the one way bearing problem we have just experienced may be the cause? The symptoms sound similar. I was getting a kick which was definately not electrical and it was too intermittant to be cause by over heating electrical connections. Check it out mate.
PS. You didn't let Wazzer anywhere near it did you?

vicrc

03-18-2008, 11:16 AM

skydude

03-18-2008, 02:44 PM

Lot's of finicky stuff on these machines. One way bearing seems ok. I thought of that as I was reading your stuff JB. It spins loose and locks up the way it should.

It is getting worse. Whereas the last two weeks it only burped once, maybe twice when I got to mid-stick this a.m. it kept it up for awhile 5 - 6 burps. Now that I am paying attention it sounds like the power is cutting out for just an instant. Not enough to drop out of the air. After a minute of this I started flying and it went fine. Second packs - no burps - flew fine??????

I called Heli direct as this has happened from day one and would certainly like to take care of it under warranty if it is a bad part. Hobby Wing esc. They said that the high voltage on the fresh pack is maybe too much. To increase the head speed???? I will see. Was at 50% (0 pitch) at mid stick with throttle at 75%. Boosted it to 80% throttle at mid stick. Seems kinda chicken $h!t but maybe it will run a little cooler also. I have maybe been running it a little slow but I am too.

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skydude

03-18-2008, 02:47 PM

Sounds like good head speed at first (fresh pack) which can cause tail kicks and then after a few minutes on the pack the HS slows enough not to kick around? After I changed out to the thrusted tail grips all is gooooooood! even at 2400-2600 rpm

I want to follow up on this thrusted tail no matter what turns out to be causing this latest. Thrusted tail. Not only does it make engineering sense it sounds good!

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istandalone

03-18-2008, 05:12 PM

Now that I am paying attention it sounds like the power is cutting out for just an instant

is it maybe a tx/rx glitch? what radio system are you using? i had an issue similar to that with my 450, and somehow my channel 3 lead was working it's way out of the rx. now that could have been disatrous!

skydude

03-18-2008, 07:54 PM

Well that was that. Set the throttle to 80% at 0 pitch as recommended by heli direct tech support. Spooled up fine. Held it for a minute on the ground to make sure. Started hovering around the front yard to test it out. Cool. Didn't stutter once in the first minute and a half like it always has. Had to be it.

No............. Stutter................. Zap.............. Hmmm. It has never made that noise before. Set it right down. Another noise? Apply power. Nothing. Flick all the switches. Nothing. Servos are moving. Blades are changing pitch but not going round and round.

Damn........

The good news is they are going to take back the esc. I decided to go for the castle creations. Twice the price. The good news to offset the extra $$$ is that I was never happy with the start up of that other one. Always kicked no matter how slowly I powered up. Got to where I wouldn't apply HH untill it was spooled up. Castle creations should be a nice set-up.

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istandalone

03-19-2008, 05:09 PM

which cc esc did you order? i run the phoenix 60 and besides the lipo cell limit being 6, it's a great esc. it's got all the features i'll ever use. although i've run 8 cell a123 with no issues.

skydude

03-19-2008, 07:27 PM

which cc esc did you order? i run the phoenix 60 and besides the lipo cell limit being 6, it's a great esc. it's got all the features i'll ever use. although i've run 8 cell a123 with no issues.

I guess it is the phoenix. I know it is a 60 amp. Almost went for the 80 as it is only another $15 but I am probably the world's sundiest flyer and will probably be for a while. I am looking forward to a smooth start-up. Is this wishful thinking? I had to think hard to not just get the same esc as a replacement. This new one was not cheap.....$118??...and some change?

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