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jeddmc
07-21-2015, 10:00 AM
I'm using jeehell v.40 why my pitch trim not function ?

try to calibrate using fsuipc but on ECAM not showing any changes when i roll the wheel



Thanks

jeehell
07-21-2015, 04:32 PM
Hello,

Only some hardware support the pitch trim, for now cockpitsonic and skalarki.
It's not possible to set the trim using other means.

JL

jeddmc
07-21-2015, 10:28 PM
Hi JL

i use flightdecksolutions hardware
maybe next develop you could make it possible



Thanks

OmniAtlas
07-22-2015, 03:49 AM
Hello,

Only some hardware support the pitch trim, for now cockpitsonic and skalarki.
It's not possible to set the trim using other means.

JL

It seems VAS has also created software for FMGS? http://www.virtualaviationsystems.com/#!software/c1u7p
I am not too sure if this would also allow compatibility with their motorize throttle.

jeehell
07-22-2015, 05:45 AM
@jeddmc: without a motorized wheel this is not possible. AFAIK, FDS do not sell motorized trim wheels...

OmniAtlas
07-22-2015, 06:00 AM
@jeddmc: without a motorized wheel this is not possible. AFAIK, FDS do not sell motorized trim wheels...

Hi JL -- FDS does sell a motorize throttle. They recently implemented it on one of their dual trainer setups for one of their customers here -- https://www.facebook.com/FlightSimKLMalaysia

jeddmc
07-23-2015, 01:20 PM
@jeddmc: without a motorized wheel this is not possible. AFAIK, FDS do not sell motorized trim wheels...

is pitch trim only run only using motorized wheel ?

jeehell
07-23-2015, 01:30 PM
no but only compatible hardware will support the trim input. The trim system is very complex, so it has to be handled correctly to avoid issues.

jeddmc
07-23-2015, 01:38 PM
no but only compatible hardware will support the trim input. The trim system is very complex, so it has to be handled correctly to avoid issues.

any suggestion non motorized wheel that compatible ?

jeehell
07-24-2015, 03:59 PM
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.

jeddmc
07-24-2015, 04:07 PM
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
07-24-2015, 08:02 PM
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
07-25-2015, 05:20 AM
You say that the Airbus has only autotrim. What does this message mean then?

OmniAtlas
07-25-2015, 06:05 AM
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
07-25-2015, 07:58 AM
You say that the Airbus has only autotrim. What does this message mean then?

how can iget that message appear ?

Fritz
07-26-2015, 06:23 AM
That's correct. I had not made any entries in the MCDU. Therefore this message appear. Thanks for the clarification.

dodiano
07-27-2015, 01:37 AM
Trim is handled on ground before taxi you set the takeoff pitch trim. After that you dont touch that wheel.

Regards

OmniAtlas
07-27-2015, 04:19 AM
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
07-27-2015, 07:51 AM
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
07-27-2015, 08:31 AM
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.

dodiano
07-27-2015, 09:46 PM
Sorry but when you land the Trim is set to 0 not 4 degrees up... And yes you trim the plane for take off after you take off and you go to Flight mode the Autotrim takes over without the Autopilot. Autotrim works with or without autopilot.

Regards

Roberto

ToTom
07-28-2015, 01:03 AM
Yes, you have a right, of course. After landing trim is reset to 0 degrees. I copied the content from website. I didn't notice mistakes.

OmniAtlas
07-31-2015, 06:24 AM
Interesting video here --


https://www.youtube.com/watch?v=8RB3GmiBmtY

andrewarles
07-31-2015, 09:02 AM
Hi all,

While we're on trim, hope you don't mind me asking some very basic questions!

I’m not clear on how the trim functions on a B737.

Firstly, am I correct in saying that the trim can be changed in 3 ways?



Trim on control yoke.
Trim wheel on TQ.
Autopilot.


Thanks

Andrew

dodiano
07-31-2015, 07:31 PM
Nice video!! Yeah steppers tend to do that! Very cool!! But that many Leds for backlighting not necessary and makes it way brighter and does not look good!