Wrong trim on V1 cut on Airbus 3XX
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Wrong trim on V1 cut on Airbus 3XX
I recently did a PC where the (newly converted) high time middle aged F/O dialed in trim the wrong way on his V1 cut.
Anybody can screw up, right?
But - a different high time middle aged F/O (newly converted) did the very same thing to me on a previous Sim ride!
Only the trainer in the back seat caught it. Both times.
These two guys had strong legs and lots of determination.
Is there a pattern?
I've flown the bus for a dozen years (in another company) and I've never seen this phenomenon before. Ever. On any type I've flown.
I'm becoming sceptical in ways I never had to be before.
Two questions arise;
1: How the heck can anyone with significant previous flying experience dial in the rudder trim in the wrong direction? Even on the scare bus!
2. Besides looking at the actual input they are making on the trim switch, how the hell do I know what they are doing? I'd rather not drag my eyes away from the PFD during a V1 cut! Anybody got a dead cert tell tale, cos I'm afraid one of these guys could kill a lot of people for real.
Anybody can screw up, right?
But - a different high time middle aged F/O (newly converted) did the very same thing to me on a previous Sim ride!
Only the trainer in the back seat caught it. Both times.
These two guys had strong legs and lots of determination.
Is there a pattern?
I've flown the bus for a dozen years (in another company) and I've never seen this phenomenon before. Ever. On any type I've flown.
I'm becoming sceptical in ways I never had to be before.
Two questions arise;
1: How the heck can anyone with significant previous flying experience dial in the rudder trim in the wrong direction? Even on the scare bus!
2. Besides looking at the actual input they are making on the trim switch, how the hell do I know what they are doing? I'd rather not drag my eyes away from the PFD during a V1 cut! Anybody got a dead cert tell tale, cos I'm afraid one of these guys could kill a lot of people for real.
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dialed in trim the wrong way on his V1 cut.
E.g. if the PF made an incorrect rudder trim input, he/she should be able to recognize pretty soon.
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Hi Meccano,
I've seen it several times in the sim - but only on the Airbus.
I believe it's because even with excess full rudder held to the stops, there is no roll input required to level the wings. The only visible effect is the Beta target will be slightly off centre.
With the extra leg force applied to the rudder stops, there is no change felt initially if the wrong trim is applied. The manual trim is slow, so the pilot waits patiently for the load to be reduced as he continues to apply the wrong trim.
Eventually the penny drops, and the correct trim is applied.
The only effect is to delay the engagement of the autopilot.
No one has come anywhere near to crashing the sim.
I'm afraid one of these guys could kill a lot of people for real.
I believe it's because even with excess full rudder held to the stops, there is no roll input required to level the wings. The only visible effect is the Beta target will be slightly off centre.
With the extra leg force applied to the rudder stops, there is no change felt initially if the wrong trim is applied. The manual trim is slow, so the pilot waits patiently for the load to be reduced as he continues to apply the wrong trim.
Eventually the penny drops, and the correct trim is applied.
The only effect is to delay the engagement of the autopilot.
No one has come anywhere near to crashing the sim.
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At takeoff thrust it takes up to a slow count of ten to get the rudder trim right. I think pilots should simply remember the trim should be steered towards the direction of the live foot as they fly the SRS. They can subsequently slowly release their foot pressure to confirm the beta target has been centred before putting on the AP. If the beta target is not yet centred, further adjustment of the trim will be required. Personally I would not look at the trim index while I am trimming out.
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At least they tried to trim it. Many others just push the AP without even bothering...
I bet that the reason for a wrong trimming is that they are not using the rudder at all. I have seen many pilots center the beta target without pressing the rudder. And many, also, use the trim control incorrectly, in short "bursts", when you have to keep it for quite a few seconds before you feel your leg unloaded.
If they don't use the rudder at all is easy to get confused to which side the A/C must be trimmed, specially if the yaw damper is doing most of the job for you.
I bet that the reason for a wrong trimming is that they are not using the rudder at all. I have seen many pilots center the beta target without pressing the rudder. And many, also, use the trim control incorrectly, in short "bursts", when you have to keep it for quite a few seconds before you feel your leg unloaded.
If they don't use the rudder at all is easy to get confused to which side the A/C must be trimmed, specially if the yaw damper is doing most of the job for you.
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This happened to my sim partner during initial type rating. Since he is ex turboprop, i guess rudder usage wasn't the issue.
After the session, a private debrief, revealed that he was in fact targeting the FD bars (which was in the opposite direction), instead of beta target. Surprising this happened... since he had already flown similar FD bars on turboprops.
Anyway, he got it right from the next session..
Our sim instructor would always repeat the phrase-
Pitch-Beta-Toga, then fly, trim comes only after these actions.
My guess is... probably the sequence of events is made so rigid by Airbus, that a new guy is too busy trying to get the sequence right rather than flying.
Of course, in due time everything becomes second nature.
After the session, a private debrief, revealed that he was in fact targeting the FD bars (which was in the opposite direction), instead of beta target. Surprising this happened... since he had already flown similar FD bars on turboprops.
Anyway, he got it right from the next session..
Our sim instructor would always repeat the phrase-
Pitch-Beta-Toga, then fly, trim comes only after these actions.
My guess is... probably the sequence of events is made so rigid by Airbus, that a new guy is too busy trying to get the sequence right rather than flying.
Of course, in due time everything becomes second nature.
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Some useful comments and theories there guys, thanks. But I still feel that only the instructor in the Sim can really see whats being done.
On the line, if it happened for real - confusion (or worse) will ensue.
Somebody made a crack about the age thing then withdrew it (or it was deleted by a Mod). I'm no spring chicken myself, and 'getting rid of dinosaurs' is not my point. I just found it strange that these quite experienced guys were doing this. Its just so basic, it seemed bizarre.
On the line, if it happened for real - confusion (or worse) will ensue.
Somebody made a crack about the age thing then withdrew it (or it was deleted by a Mod). I'm no spring chicken myself, and 'getting rid of dinosaurs' is not my point. I just found it strange that these quite experienced guys were doing this. Its just so basic, it seemed bizarre.
