Surface position indication

[Dispatcher]

Hello, I got a question about the surface position indication on the sec. EICAS:
when I move the cloche (joystick), my impression is that this indication shows just the actual displacement of the cloche instead to "wait" for the full deplacement of the surfaces.
If I move for example the cloche (joystick) full left very fast, i expect to have to wait to see the arrows going to the full left position (corresponding to the time that the surface needs to move), but on the PSX the arrows go to the full position right away (together with the cloche movement). The same happens for the rudder.
Is that the right behavior on the B747?
Shouldn't the arrows indicate the actual position of the surfaces as reported on the FCOM?

Thanks!
Marco

[Hardy Heinlin]

Hi Marco,

I disagree with your observations. The EICAS indications don't go instantly to the max; they travel smoothly to the max which takes ca. 300 ms. You may consider 300 ms a very fast rate. But the hydraulic mechanism is very fast indeed. You may watch videos of landings in stormy weather and observe the aileron, rudder and elevator surfaces.


Cheers,

|-|ardy

[Dispatcher]

Hello Hardy,
that's clear, the displacement of the surfaces is that fast itself.
Thanks
Marco