pitching up

[v2flier]

While flying in moderately fast foward flight with an Align 450 flybarless 3G system it pitchs upward suddenly I mean strait up before I can correct it.I've tryed adjusting pitch gyro up to the point where it ossilates rapidly in hover and adjusted gyro down to where forward flight it pitchs down violently, their's only a small adjustment range that suits my low skill level.Increasing rotor speed helps reduce pitch up tendency.I believe Ray Hosteter called this "disc blowback".I'm unable to access information on the computer disc that came with the system my computer simply refuses to read the disc.Until I find a solution I'm restricted to slow 12mph or so forward flight.Any helpful imput would be appreciated.

[zeta30]

That is a common issue with the Align 3G and also 3GX FBL controllers. Some people are able to fix the issue by reducing the elevator gain, others say it's a COG issue with the heli being tail heavy. Most of the threads I've read say that the only way they were able to solve the issue is to ditch the 3G and go with a better controller like BeastX or V-Bar.

Here is a link you can try to see if these settings will help...

http://www.helifreak.com/showthread.php?t=338904

[v2flier]

OK I went to that link and found he is haveing success with a higher head speed, so when my repairs are complete I'll try increasing head speed to the limit of stock Align 3g rotor blades,which is lower than RPM maximums listed in the Align manuel and see if that helps enough.

[zeta30]

What head speed have you been running?

[v2flier]

It's been so long since flying my trex due to repeated crashs and repairs and discouragement due to this issue, my best recolection is near 2800 rpm maybe less. The replacement package of 3g rotor blades gives a max RPM of ? I don't recall, but it's well lower than the 3400 max RPM stated in the Align owners manuel, so I've kept the head speeds below the max allowed on the replacement package.My very next step is to visit a hobby shop and examine a package of 3g blades to establish the max recomended RPM.
Update;Checked online and 2800 RPM max is whats stated for Align replacement 3g blades.