Su-27 Question : Roll amplitude on α, Пу КРИТИЧ

[Scoll]

Is it normal to have stick Roll (but not pitch) amplitude reduced by half(or more) when "α, Пу КРИТИЧ" is on ?

[ShuRugal]

sounds like you have engaged bank-hold AP.

[Scoll]

ok, i should be more precise, start motors, thrust, take off, moving gears and flaps, trim. nothing else. Apply full left or right move on stick and look at his amplitude(clearance). Then, engage plane until "α, Пу КРИТИЧ" lights on, apply same move full left or right on the stick and look at his amplitude. About 1/3 of full, in standard flight, amplitude for me. Same behavior in "s" mode.

[combatace]

I think rather then angle of attack it is showing angle of incidence.

[Scoll]

Edited December 1, 2014 by Scoll

[Esac_mirmidon]

"α, Пу КРИТИЧ" light on indicates Maximum AoA, G reached so if you have this limiter ON the SAU system limits your stick movement like in real life to avoid movements beyond limits.

 

First making harder to move the stick, (more force needed to move it) and if you still pushing it beyond limits, forcing a hard shake on the stick to return it to the center.

 

So it´s normal behaviour.

[Scoll]

i agree, but then, why this apply only on left/right stick move and not on push/pull stick move ?

BTW i use the "s" mode, ACS disengage(pushed forward)

Edited December 1, 2014 by Scoll
precision on "s" mode

[Esac_mirmidon]

Maybe because the pitch channel is the only one working through FBY and maybe this channel works with a different logic. Roll and bank are not linked to FBY. But i´m not sure this will be the cause.