A320 nose wheel tiller
Thread Starter
Joined: Sep 2021
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From: Area51
A320 nose wheel tiller
During taxying, if you observe that one of the tiller is unserviceable, would you continue or not? The MEL is silent on the tiller part. It only makes a note of the Nose wheel steering. I am assuming that since it's not mentioned in the MEL it has to be a "NO GO". Any thoughts?

Joined: Mar 1999
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From: big green wheely bin
If you are taxiing the MEL is not relevant. It would be a discussion with maintenance and a command decision, taking into account the MEL, but not ruled by it. As far as actual controllability, you still have rudder pedal steering and differential braking, in addition to the serviceable tiller.
Thread Starter
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From: Area51
If you are taxiing the MEL is not relevant. It would be a discussion with maintenance and a command decision, taking into account the MEL, but not ruled by it. As far as actual controllability, you still have rudder pedal steering and differential braking, in addition to the serviceable tiller.
Thread Starter
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From: Area51

The MEL only mentions about the NWS control system. The number installed is 1 as you can see. Meanwhile, there are 2 tillers available.

Joined: Mar 1999
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From: big green wheely bin
Looks like if the tiller is U/S the aircraft is AOG. I would imagine this is because the failure mode of the tiller cannot be determined and therefore it must be fixed before dispatch.
If an item cannot be deferred in accordance with the MEL, either because it says not, or because it’s not mentioned, then the aircraft is AOG. The only get out is if it’s clearly a non airworthiness item.
If an item cannot be deferred in accordance with the MEL, either because it says not, or because it’s not mentioned, then the aircraft is AOG. The only get out is if it’s clearly a non airworthiness item.

Joined: Mar 2006
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From: USA
I’d be going back to the gate. There must be some way to deactivate the affected tiller. I wouldn’t want it to send an erroneous signal while I’m on the runway.
I’ll have to see what our MEL says about it.
I’ll have to see what our MEL says about it.
Joined: Mar 2007
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From: Here and there
I was always taught that if a component is not in the MEL then you are AOG if it is broken. The company maintenance will have access to the MMEL which will be more comprehensive but why would what is effectively an electric switch fail on one side? Liquid in that area ? Where else has it gone? Into the sidestick? Back to the gate and look at the empty coffee cup you put in that area when you know that it shouldn’t have been there.
Only half a speed-brake

Joined: Apr 2003
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From: Commuting not home
As you remember for long years until recently, on the SA bus NWS INOP dispatch was permissible. The OP is asking about 1 tiller u/s ...
Additional thoughts
+ CAT III single with manual roll-out is permissible with NWS u/s
+ the post-maintenance check flight schedule prescribes separate verification of tillers Left and Right actually on 2 separate occasions (Airbus reference IS-ATFM E8 & F4).
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From: Utopia
Don’t forget that you may not be able to make a 180 degree turn without a tiller. Let’s suppose that the Captain side tiller became inoperative during taxiing, and the pilot sitting on the right side is still wet behind the ears. Handing over the controls to the this pilot to make a 180 degree isn’t exactly what I would be looking forward to.


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From: USA
Don’t forget that you may not be able to make a 180 degree turn without a tiller. Let’s suppose that the Captain side tiller became inoperative during taxiing, and the pilot sitting on the right side is still wet behind the ears. Handing over the controls to the this pilot to make a 180 degree isn’t exactly what I would be looking forward to.
Only half a speed-brake

Joined: Apr 2003
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From: Commuting not home
Would you trust a captain to make a 180 he's never done before? WTF.
Nope. Because he has been through the excerise during the TR course and base training. Same as the F/Os.
Better focus on the fact that A319 cannot go over the edge line, buddy.
Nope. Because he has been through the excerise during the TR course and base training. Same as the F/Os.
Better focus on the fact that A319 cannot go over the edge line, buddy.
Last edited by FlightDetent; 19th September 2022 at 00:30.

Joined: Jul 2005
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From: Here and there....currently here.
From an Engineering point of view, the answer is as the MEL quoted above. It comes down to it being one system, which includes both tillers. If any part of the control system is not functioning correctly, the whole system is classed as inop, so a no-go. If it was allowable to have one tiller inop, it would be in the MEL as a separate item.
Thread Starter
Joined: Sep 2021
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From: Area51
From an Engineering point of view, the answer is as the MEL quoted above. It comes down to it being one system, which includes both tillers. If any part of the control system is not functioning correctly, the whole system is classed as inop, so a no-go. If it was allowable to have one tiller inop, it would be in the MEL as a separate item.

Joined: Jun 2006
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From: B.F.E.
May not be helpful to you, but for perspective on use of the MEL after pushback, in US / FAA regulations there is a process we are bound to between pushback and takeoff called “crew placarding”. Essentially the MEL still applies during taxi, until airborne. If an issue arises during taxi-out, once completing the ECAM or other procedure we have to reference the MEL (generally while on the phone with maintenance) and see if an item is crew placard-able. If yes and everyone agrees, we complete the required operational items from the MEL (has to be very simple, like pulling a breaker), get the required paperwork from our maintenance and dispatch offices (over ACARS), and then press on. The tech log is filled out enroute in accordance with the instructions and authorization on that ACARS printout.
If an item is not placardable (which is true in this case since it is not on the MEL at all!), back to the gate we go.
If an item is not placardable (which is true in this case since it is not on the MEL at all!), back to the gate we go.





