Pitch Trim

[jeddmc]

none
There probably was a misunderstanding:
- Pitch works in the software without any hardware (the auto trim will set the trim to stabilize the aircraft, this can be seen in FLT CTL page).
- Only hardware with motorized trim can work in theory. For now, only compatible modules are skalarki and cockpitsonic.

i see....

even i roll manual the pitch it want change trim value on FLT CTL page because its auto by software

[OmniAtlas]

The airbus has autotrim. I am not too sure if this can be disabled like the 737. Perhaps on the OVH? Rudder trim can be manipulated on the pedestal.

What happens on the even of an elevator surface failure? How would you control the aircraft?

I am sure there has been some real world example some where....

[Fritz]

You say that the Airbus has only autotrim. What does this message mean then?

[OmniAtlas]

The airbus has autotrim in ADDITION to manual trim
If you are in direct law it looks like you can manual trim. Otherwise I don't believe you trim the aircraft because it auto trims when you enter the zero weight fuel in the MCDU, and start the engines.

On the Boeing 737 you have to trim the aircraft prior to the T/O procedure.

[jeddmc]

You say that the Airbus has only autotrim. What does this message mean then?

how can iget that message appear ?

[Fritz]

That's correct. I had not made any entries in the MCDU. Therefore this message appear. Thanks for the clarification.

[dodiano]

Trim is handled on ground before taxi you set the takeoff pitch trim. After that you dont touch that wheel.

Regards

[OmniAtlas]

Yes, my mistake!

I haven't been trimming the aircraft prior to T/O because I haven't assigned trim to joystick buttons!

If you are out of trim, is autotrim inhibited in the TO stage? Or does it only take into effect when you turn on the autopilot?

Regards.

[ToTom]

See this:
http://www.airbusdriver.net/airbus_fltlaws.htm
Before TO => ground mode.

Ground mode is active whilst the aircraft is on the ground. The autotrim feature is turned off and there is a direct relationship between sidestick deflection and elevator response. The horizontal stabilizer is automatically set to 4° up but manual settings (e.g. for center of gravity) override this setting. Immediately after the wheels leave the ground, flight mode progressively takes over from ground mode. The reverse occurs after touch down during the landing phanse.

http://www.skybrary.aero/index.php/Flight_Control_Laws

[OmniAtlas]

Thank you for the links ToTom, it is always good to revisit and remind myself of these laws

Perhaps someday JL can also implement software base trim (joystick button assignment trim+/-)

Thank you.