Michael211

My Feedback: (1)

Hey ya'll! I already read what's been posted on this subject and I didn't find anything that seems to match what I'm seeing here.

Another club member and myself are flying X-Cell ST .60 sized heli's at our club field and we're both using Futaba radio equipment (he's on channel 32 and I'm on 60; both late model FM radio's and receivers).

I've been flying mine for over a year now and solved, I thought, all my glitches when I took the antennae wire off the side frames of my X-Cell and installed a base loaded whip antennae last Fall.

My flying buddy just started learning to hover his X-Cell this past month and for the most part it's been working well for the 1st 5 or 6 flights but...

This past Sunday we were out at the flying field and while hovering about 30 feet away 5 feet up my buddy's X-Cell just started flipping out, jumping up and down and the tail swinging wildly left and right... but it only lasted for a few seconds then seemed to settle down and fly right again. Needless to say he was spooked!

He put his X-Cell up to rest for awhile after flying out that tank of fuel, so I took mine out to the starting line and lit it up and took off to do some figure 8's... but mine started jumping spontaneously in the air every few minutes. During my tank of fuel that flight I must have gotten between 4 and 5 hard glitches!

What the heck is going on here? My machine has been very well behaved for the past 10 months or more with no problems, and suddenly mine and my friend's heli's are both acting possessed and we're not even on the same channel! He's using a Futaba 7C with a 127DF receiver on channel 32 and I'm using a Futaba 9C with a 148DF receiver on channel 60 and we both have base loaded whip antennaes that are nowhere near any of the servo wires or anything metal.

I went ahead and did another full-tank flight with mine and was continuing to get constant glitching.... more glitches in those 2 flights than I've had in the past 10 months since I changed my antennae to the base loaded one.

There were some storms in the area earlier that day, but they had mostly cleared out by the time we started flying obviously. Could atmospheric conditions be affecting the radios? I changed model memory to my Mustang and flew it and had no problems.

Oh and 1 other thing I noticed with my heli was that when I hooked up the glow driver and then went to insert the starting wand into the hex starter on the heli, all my servos JUMPED something fierce. It normally doesn't do that. This time it did it both times I started it, the servos were going nuts until I removed the starting wand.

Please comment or give me your thoughts on this. I've no idea what was going on or why. Before I packed up for the day I tried to reproduce the servo jumping problem with the starter wand and nothing happened.... the servos just sat there with everything hooked up ready to start. Previously during that day it'd go nuts though and I can't imagine what the difference was.

Thanks!

- Michael

BarracudaHockey

My Feedback: (11)

You either have metal to metal rubbing somewhere like a loose fastener or a bad bearing.

soop7667

You know I've got servo leads going across my Spektrum AR7000 Receiver, and it NEVER glitches at all. NO GLITCHES WHATSOEVER! You know Michael - You may have a legitimate reason to change over to Spread Spectrum.

Michael211

My Feedback: (1)

"metal to metal rubbing "

That doesn't explain why the servos all jumped and went crazy when I went to start the heli (before actually turning the engine over with the starter).

I'm inclined to doubt there's a mechanical metal to metal reason as a result.

I'm all for switching to 2.4gig, however I'm waiting for Futaba to get with the program and release a 2.4gig FASST 9CH transmitter. Right now they've only release a 7C and a 12C transmitter, and I'm not satisfied with the rf module replacements offered by Futaba or Spektrum for my current 9C.

I've got issues with some of the other club members who also fly on 72mhz (leaving transmitters lying around all over the place, hogging the frequency pin for hours at a time even going off to eat lunch, with the blasted pin still on their transmitter, etc.). It just isn't worth flying 72 mhz in a club environment anymore IMHO.

The weather here in Houston is clear sunny and not so humid today so I'm going to slip out to the club field with my heli and give it a spin this afternoon and see if she glitches any or not.

- Michael

Rafael23cc

My Feedback: (6)

You are new to the heli section of RCU, aren't you? BH will not lie to you, look hard and you will find it. How old are the helis? How many flights?

What material is your starter wand made of? What material is your starter coupler made of? They are both made of metal, as in metal to metal contact, when you just touch the wand to the starter coupler, that part is somewhat normal. The glitching while flying is not normal.

Rafael

tippy

A 127DF and a 148DF.

Two PPM RX's ... hmmm?

I have one those little Radio South glow starters. I had no problems whatsoever using PPM until the day I started using this starter (the new smaller yellow one). When I would attached it to the remote plug ... the servos would go crazy. I emailed Radio South and they said to switch to PCM.
I did and no problems since.

What starting equipment are you using??

badazzbusa

My Feedback: (1)

I agree with Rafael, The glitches while starting are not a concern. It's just the metal to metal from the starter, sometimes it will do it and sometimes it won't. Your friends heli sounds like it was getting hit really bad. I know you probably already did but check all his metal to metal faseners for end play, sometimes you will get a little play on the sleeves they ride on. Good luck and let us know what you find out.

Michael211

My Feedback: (1)

Ok now, I never said anybody was lying here guys.... I asked for opinions/comments and I appreciate them all!

My heli is all of 15 months old now. I bought it used, but it had only been partially assembled and had never seen fuel or airtime. My friend's heli is a bit older and has the nicer XL-Pro all metal head (damned smooth flying head too I want one!). Both are pretty quite mechanically speaking once you kill the motor after a flight, while the blades and all are spooling down without the engine running. In flight about all I hear is the sounds of the blades cutting thru the air.

I did 3 full flights this afternoon from 5:30 till 7:30pm, each about 15 minutes long, without a single noticeable glitch occurring. Even when inserting the starter wand the heli servos just sat there quite and still every time. It was totally opposite of what was going on this weekend and confounds me! [&:]

Can the servo leads pick up stray signals off of the heli frame? My friend's is all carbon fiber and mine has the carbon fiber tail tube with aluminum side frames.... we both have the whip antennae's which are mounted up front and go nowhere near the frames, so the only way I can think of for the radio electronics to pick up interference is thru the signal wires of the servos (the elevator servo in particular sits behund the main shaft and has it's wire run along the side of the frame). If so, what can be done about that?

Thanks!

- Michael

Michael211

My Feedback: (1)

I'm using a Royal starter motor (pretty ancient, maybe 25 years old now) with a deep starter cone and a Maverick push-in starter wand (w/one way bearing), and a standard wired glow driver that connects to my power panel.

Usually I connect the glow driver to my engine (directly to the glow plug, I don't have a remote yet but plan to get one eventually), then turn on my radio equipment and let the gyro initialize, then activate the glow driver via a rocker switch on my panel, and finally insert the starter wand into the hex adapter on the engine shaft and spin the engine up to start it. When the servos jumped and went nuts was when I was inserting the starter wand into that hex adapter, and the servos continued to go nuts until I removed the starter wand after the engine had started running.

Is that the information you wanted to know? On my 3 starts this afternoon the servos never so much as quivered during the starting procedure. I can't imagine what was so different this weekend that it was causing so much havoc! [:@]

Thanks!

- Michael

Michael211

My Feedback: (1)

"check all his metal to metal faseners for end play, sometimes you will get a little play on the sleeves they ride on"

I'm not understanding what you're talking about here. I've checked everything on his heli for correct fit (in other words, everything is snug that's supposed to be snug and nothing is loose or wrong that I can find.... his heli is almost exactly the same as mine if a bit older and with a few more upgraded parts like the XL-Pro head).

Faseners, sleeves... I don't think these heli's have any such things. It's all ball bearings everwhere I can think of. Uhmmm... can you give me a specific example of what you're referring to perhaps? Maybe I just don't recognize what you're talking about here.

I think that since my friend is just starting to learn to hover that when his heli glitched he was slamming the throttle/collective down and possibly giving it some rudder as well in a panic. Hey, it'll make you need a change of shorts when one of these birds suddenly jumps up or down all by itself!!! LOL!

I'm just experienced enough that when mine was glitching in flight this weekend I kept flying it thru the glitch without letting it affect me... and I was alot higher up anyhows so trying to sit it down in a panic was pretty much not an option up there.

Thanks!

- Michael

tippy

You'd be concerned if the glitch was on the throttle servo .... [X(][X(]

FLYBOY

My Feedback: (11)

What batteries are you using? If they are NiMh and fully topped, that will cause some glitching, but not all the time. It is a pain. A friend just crashed a huge 42% bird due to it. I have seen it before and it is tough. Might not be the problem, but is something to look at. Otherwise, check that all your bearings are clean. A rusty one will cause this problem.

Michael211

My Feedback: (1)

Actually, it did include the throttle servo when starting... but as soon as the engine fired up I pulled the wand out so it didn't have time to cause any harm. That glitching at least ceased once I removed the starter wand.

But then flying figure 8's at about 65 feet up the heli would glitch (almost like convulsing if it were a living thing) for a second every minute or two during the flight. It was spooky! And none of that happened on today's 3 flights even though I haven't changed a thing!

- Michael

Michael211

My Feedback: (1)

Actually they are NiMh battery packs on both heli's. These packs are heavy duty and are supposed to be rated for 60-90 sized heli's with coreless servos. However I didn't recharge between my flights last Saturday (ergo voltage would have dropped some each flight) and the glitches occurred during every flight, on both machines.

My heli isn't that old (IMHO) and is kept inside the house in the back of my computer room... seems unlikely it would have a rusty bearing. The tail unit clicks as it turns over but I've pulled it apart and checked the bearings and they all felt smooth... it has metal gears and I'm guessing that's what the clicking must be about. Otherwise I have not noticed anything wrong with any of the bearings in mine when I've pulled the main shaft or clutch out, and I check everything every time I pull it apart for any reason. I had to replace the clutch liner recently and everything felt very smooth. And finally of course it flew fine today for 3 more full flights and I haven't changed a thing I swear!!!! [:@]

LOL!

When Futaba comes out with a FASST 9C radio I'll probably upgrade to it and see what if any effect that has. Can't 2.4 gig still be interferred with though by most of the same things that effect 72 mHz?

I have a Gem 2000 rx monitor unit that I've never installed, would it possibly help diagnose the problem if this re-occurrs in the future? I was saving it for 1 of the navigation lights for the Airwolf model I'm working on though.... didn't intend to put a Gem 2000 on my pod-n-boom X-cell but now thinking maybe I aught to.

Thanks.

- Michael

Michael211

My Feedback: (1)

Oh here's one more oddity that seems related to the problem... almost every time we tried hovering my friend's X-Cell over this concrete heli pad at our club field Saturday, his would glitch horrifically!

I even flew it over the pad at about 4 feet up and the heli jumped a good foot or so uncontrollably without me touching the sticks, and it was far faster than I could replicate using the left-hand stick on the TX when I tried it out over the grass field. I don't know if there's some metal reinforcement in that heli pad or what but it seemed damned consistant that flying his heli over that 8 foot diameter concrete pad would cause it to jump... and violently. When he was trying to hover it out over the grass it also jumped slightly ever few minutes but not nearly as severly as when over that pad.

We were standing about 20-25 feet or so from the concrete heli pad when his heli would go nuts hovering over it.

When I was learning to hover with my own X-Cell I did most of my flying from that same heli pad for months and mine never jumped over the pad like his was doing Saturday. I didn't think to try holding mine over the pad that day to test if it would do the same thing or not... in hindsight it would have been interesting to see if mine would have glitched over the heli pad Saturday as well. I don't like playing russian-roulette with these glitches however....

- Michael

BarracudaHockey

My Feedback: (11)

The frequency created by metal to metal rubbing won't approach anything close to 2.4G

If you were at the field a day that nobody was there and didnt have a problem vice a busy day then I would suggest one of two things.

1. Send your reciever to Radio South or Hobby Services and have it checked/tuned

2. Get a PCM reciever and be done with it.

I dont advocate not finding what is causing the glitch but if its just happening from a noisy RF enviroment or a cracked crystal filter in your reciever then 1 or 2 should fix it.

Other wise you need to strip down the helicopter and put turn every high speed bearing by hand to find out which one is notchy. Its one or the other.