bob00
08-17-2005, 11:02 PM
I think I'm seeing what Chuckie described in this earlier post...
http://www.helifreak.com/about7094.html
I've seen this now 3 times on two different helis. The elevator seems to twitch - as if responding to a quick stab of back cyclic - just enough to make the tail bounce. The weird thing is the Rx does NOT go into failsafe - the elevator simply kicks - once it starts it's pretty persistent.
Saw this on my Hacker Ion about 2 weeks before Ircha - last flight of the day on the second visit to the field that day. Tail started bouncing in a steady hover - didn't go into FS, just sat there with the tail kicking up and down. Thought it was the heli so I set it aside for a while.
The exact same thing started happening with my R90 last night. Tail started bouncing around in a low piro-hover - very noticable. The engine did NOT drop to idle so it definately wasn't going into FS. The Tx battery was a bit low (47%) so I poped in a fresh pack, we took the blades off and tried to reproduce the problem - couldn't. The heli flew fine for the rest of the evening.
This evening - same thing, I saw a bogus back elevator input on spool-up. This continued in a hover. Took it up high and switched to IDLEUP - no change - elev. kept twitching while the motor held a nice consistent note. Hit HOLD and auto'd it in with the tail bobbing all the way down.
Checked the usual things, poked around the wiring looking for loose servo leads - nothing out of the ordinary. I was pretty conviced that the Tx was the problem 'cause it would be extremely unlikely that 2 different make / model helis could experience ELEV servo failure at the same time - esp. given that both are low time machines.
Noticed the Tx pack was reading 56% so I popped in a fresh battery, refueled and tried to repoduce the problem for half a tank - nothing - problem gone. Strange, cause the heli was less than 15ft away when this started happening this evening so range could not have been an issue, plus all ather controls worked just fine.
- problem seen on 2 make / model helis, always the same brief, false back elev. cyclic input - pretty much rules out a failing elev. servo
- problem seems to occur when Tx battery discharged < 60%
- all helis have G3 Rx's
- Rx never goes to FS (failsafe), all other controls function normally
- both helis run 7.4v lipo w/ duralite 5.1v and 5.3v regulators
- problem observed this evening with genuine Futaba Tx battery
Never had any other glithing problems with this radio. Will try to reproduce the problem tomorrow evening then copy the model to another 14mz and try it with the same battery.
Has anybody else seen anthing like this?
Any/all input appreciated
- Rob
http://www.helifreak.com/about7094.html
I've seen this now 3 times on two different helis. The elevator seems to twitch - as if responding to a quick stab of back cyclic - just enough to make the tail bounce. The weird thing is the Rx does NOT go into failsafe - the elevator simply kicks - once it starts it's pretty persistent.
Saw this on my Hacker Ion about 2 weeks before Ircha - last flight of the day on the second visit to the field that day. Tail started bouncing in a steady hover - didn't go into FS, just sat there with the tail kicking up and down. Thought it was the heli so I set it aside for a while.
The exact same thing started happening with my R90 last night. Tail started bouncing around in a low piro-hover - very noticable. The engine did NOT drop to idle so it definately wasn't going into FS. The Tx battery was a bit low (47%) so I poped in a fresh pack, we took the blades off and tried to reproduce the problem - couldn't. The heli flew fine for the rest of the evening.
This evening - same thing, I saw a bogus back elevator input on spool-up. This continued in a hover. Took it up high and switched to IDLEUP - no change - elev. kept twitching while the motor held a nice consistent note. Hit HOLD and auto'd it in with the tail bobbing all the way down.
Checked the usual things, poked around the wiring looking for loose servo leads - nothing out of the ordinary. I was pretty conviced that the Tx was the problem 'cause it would be extremely unlikely that 2 different make / model helis could experience ELEV servo failure at the same time - esp. given that both are low time machines.
Noticed the Tx pack was reading 56% so I popped in a fresh battery, refueled and tried to repoduce the problem for half a tank - nothing - problem gone. Strange, cause the heli was less than 15ft away when this started happening this evening so range could not have been an issue, plus all ather controls worked just fine.
- problem seen on 2 make / model helis, always the same brief, false back elev. cyclic input - pretty much rules out a failing elev. servo
- problem seems to occur when Tx battery discharged < 60%
- all helis have G3 Rx's
- Rx never goes to FS (failsafe), all other controls function normally
- both helis run 7.4v lipo w/ duralite 5.1v and 5.3v regulators
- problem observed this evening with genuine Futaba Tx battery
Never had any other glithing problems with this radio. Will try to reproduce the problem tomorrow evening then copy the model to another 14mz and try it with the same battery.
Has anybody else seen anthing like this?
Any/all input appreciated
- Rob