Trim setting?
Thread Starter
Join Date: Dec 2010
Location: Ireland
Posts: 1,167
Likes: 0
Received 0 Likes
on
0 Posts
Trim setting?
Hi everyone! I'm just confused with another Airbus issue,
In the 737NG series trim is set manually, But yesterday I learned that the Airbus automatically sets trim for take-off. What I was precisely told was an aircraft taking off in CONF 3 sets the following;
FMGC -> PERF -> TAKE OFF -> FLAPS/THS = 3/0
Is this correct? And if not and say the aircraft needed a take off trim of 2.6DN how would it be set in the FMGC e.g. what would be put in the FLAPS/THS option?
Very much appreciated, Thanks!
In the 737NG series trim is set manually, But yesterday I learned that the Airbus automatically sets trim for take-off. What I was precisely told was an aircraft taking off in CONF 3 sets the following;
FMGC -> PERF -> TAKE OFF -> FLAPS/THS = 3/0
Is this correct? And if not and say the aircraft needed a take off trim of 2.6DN how would it be set in the FMGC e.g. what would be put in the FLAPS/THS option?
Very much appreciated, Thanks!
Join Date: Mar 2006
Location: Choroni, sometimes
Posts: 1,974
Likes: 0
Received 0 Likes
on
0 Posts
FMGC -> PERF -> TAKE OFF -> FLAPS/THS = 3/0
TO trim setting is achieved with FMGC input ZFWCG/ZFW.
Join Date: Jun 2006
Location: Sandcastle 2
Age: 39
Posts: 65
Likes: 0
Received 0 Likes
on
0 Posts
The Airbus does not set takeoff trim automatically, we have to set it. The value we enter in the Takeoff performance page is only there as a reminder.
Not exactly correct as that is the ZFW trim setting, not the TOCG.
The TOCG we have calculated by either using the Loadsheet (if you're in the dark ages) or the LPC is indeed entered like you say on the Takeoff Performance page, and in your example if you wanted 2.6DN and a Flap 3 takeoff you would put 3/2.6DN in the FMGC.
As I said though this is only a reminder, so after engine start we would set 2.6DN using the trim wheel.
TO trim setting is achieved with FMGC input ZFWCG/ZFW.
The TOCG we have calculated by either using the Loadsheet (if you're in the dark ages) or the LPC is indeed entered like you say on the Takeoff Performance page, and in your example if you wanted 2.6DN and a Flap 3 takeoff you would put 3/2.6DN in the FMGC.
As I said though this is only a reminder, so after engine start we would set 2.6DN using the trim wheel.
The newest A330's in our fleet set the stab trim automatically during start.
This from FCOM 1
The THS is automatically set at 4 UP (inside the green band). Before departure, as soon as the three hydraulic systems are available, the THS is automatically set to the takeoff value, calculated by the PRIM, according to the ZFWCG entered in the MCDU and the fuel distribution
This from FCOM 1
The THS is automatically set at 4 UP (inside the green band). Before departure, as soon as the three hydraulic systems are available, the THS is automatically set to the takeoff value, calculated by the PRIM, according to the ZFWCG entered in the MCDU and the fuel distribution
Last edited by nitpicker330; 24th Aug 2012 at 12:45.
Thread Starter
Join Date: Dec 2010
Location: Ireland
Posts: 1,167
Likes: 0
Received 0 Likes
on
0 Posts
Thanks for the replies everyone! 
Yeah that's what I originally thought, thanks!
The Airbus does not set takeoff trim automatically, we have to set it. The value we enter in the Takeoff performance page is only there as a reminder.
