limitation on taxi speed
Thread Starter
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From: Rome
limitation on taxi speed
Hi guys
regarding the limitation on taxi speed, the manual says ... when taxi weight is higher than 76 000 kg do not exceed a taxi speed of 20kt during a turn, the limitation is only applicable for the A320CEO and not for the NEO, I wonder why, why is there a limitation on taxi speed at all, it there a tyre issue, nose wheel skidding?
regarding the limitation on taxi speed, the manual says ... when taxi weight is higher than 76 000 kg do not exceed a taxi speed of 20kt during a turn, the limitation is only applicable for the A320CEO and not for the NEO, I wonder why, why is there a limitation on taxi speed at all, it there a tyre issue, nose wheel skidding?
Joined: Apr 2008
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From: Nearer home than before!
Turning an aircraft at speed is not particularly clever at the best of times..... you get significant wear and tear to nose wheels as well as some seriously pissed of crew down the back......
Joined: Jul 2007
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From: Germany
Hi guys
regarding the limitation on taxi speed, the manual says ... when taxi weight is higher than 76 000 kg do not exceed a taxi speed of 20kt during a turn, the limitation is only applicable for the A320CEO and not for the NEO, I wonder why, why is there a limitation on taxi speed at all, it there a tyre issue, nose wheel skidding?
regarding the limitation on taxi speed, the manual says ... when taxi weight is higher than 76 000 kg do not exceed a taxi speed of 20kt during a turn, the limitation is only applicable for the A320CEO and not for the NEO, I wonder why, why is there a limitation on taxi speed at all, it there a tyre issue, nose wheel skidding?
My type has specific fuel limits also as the rush of fuel to one end of the wing tank can seriously damage the internal fuel baffles if you give it some welly in the turn above 20 Kt.
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From: Rapunzel's tower
It mightn’t be helpful to efficiency targets but it’s something to deal with, and understand. From an ATC point-of-view I will (almost always) ask crew if they are able “expeditious backtrack” etc if the gap is tight. If not, I’ll alter my plan. It’s not rocket science, nor is it ununderstandable...
In ATC terms we need to know if you can accept a rocket-propelled backtrack, or not. It affects what we do. It affects how (certainly) “my” airport operates.
So yes, this is where aviation has gone, and where it will be centred on....customer experience, positive (hopefully) reviews and recommendations. Not rocket science...
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From: Earth
In a bid to satisfy the customer? The customer is (nearly) always right, come the bottom line. In these days of social media the views of the end-line customer prove to be very effective. Do your customers want to be thrown about? (Depends on customs, I suppose.) AFAIK many airlines have SOPs which generally prevent their customers from being unnecessarily thrown about in the cabin. Seems reasonable, given the flack?
It mightn’t be helpful to efficiency targets but it’s something to deal with, and understand. From an ATC point-of-view I will (almost always) ask crew if they are able “expeditious backtrack” etc if the gap is tight. If not, I’ll alter my plan. It’s not rocket science, nor is it ununderstandable...
In ATC terms we need to know if you can accept a rocket-propelled backtrack, or not. It affects what we do. It affects how (certainly) “my” airport operates.
So yes, this is where aviation has gone, and where it will be centred on....customer experience, positive (hopefully) reviews and recommendations. Not rocket science...
Joined: Jul 2000
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From: somewhere hot and sticky
You started your post by highlighting the reason why an aircraft taxis is nice and slow; passenger comfort. Then as a controller you ask a pilot to expedite his taxi so your airport can run efficiently, disregarding passenger comfort. What’s your point really? Anyway, I didn’t think someone had to ask why one can’t taxi around a corner at 20+ kts.
Also, as I am not involved in type certification/testing, I don't know what the limitation is the designers had in mind when they designed that 76t,/20kt limit, nor why this reason magically disappeared on the NEO. If this is so obvious, maybe you could enlighten us?
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From: United Kingdom
Joined: Feb 2006
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From: Rapunzel's tower
You started your post by highlighting the reason why an aircraft taxis is nice and slow; passenger comfort. Then as a controller you ask a pilot to expedite his taxi so your airport can run efficiently, disregarding passenger comfort. What’s your point really? Anyway, I didn’t think someone had to ask why one can’t taxi around a corner at 20+ kts.
Before this drifts too much, it’s good for ATC to know operator limitations. It’s also good to know these limitations when modelling airport capacity.
I’m guessing the 20kt limitation above doesn’t include initial turn onto RET (shallow turn radius) after landing but is a limit for standard turn radius on taxiways and taxiway intersections?
Last edited by good egg; 10th August 2018 at 03:47. Reason: More explanation
Joined: Jan 2014
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From: N5109.2W10.5
why is there a limitation on taxi speed at all, it there a tyre issue, nose wheel skidding?
It is more likely to be a sideways nose gear loading limit. Maybe the NEO has a stronger nose gear.
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From: SEQ
In any event, considering the max Landing weight of an A320 CEO is 66t, so clearly it is not an issue.
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From: Rapunzel's tower
What makes you say that? That's as logical as the pilot that turns the brake fans off 5sec before departure and says, "fans are off so the temp limit is now 300 degrees". A limitation is a limitation. There is no note or exception for RET.
In any event, considering the max Landing weight of an A320 CEO is 66t, so clearly it is not an issue.
In any event, considering the max Landing weight of an A320 CEO is 66t, so clearly it is not an issue.
Joined: Feb 1999
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From: MAN
Hi guys
regarding the limitation on taxi speed, the manual says ... when taxi weight is higher than 76 000 kg do not exceed a taxi speed of 20kt during a turn, the limitation is only applicable for the A320CEO and not for the NEO, I wonder why, why is there a limitation on taxi speed at all, it there a tyre issue, nose wheel skidding?
regarding the limitation on taxi speed, the manual says ... when taxi weight is higher than 76 000 kg do not exceed a taxi speed of 20kt during a turn, the limitation is only applicable for the A320CEO and not for the NEO, I wonder why, why is there a limitation on taxi speed at all, it there a tyre issue, nose wheel skidding?
Joined: Feb 2006
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From: Rapunzel's tower
Its is funny the forth right opinion on here, wrong as most of it is. Its got nothing to do with the nose gear. The issue affects all 'heavy' jets, the higher the weight the higher the tyre stress and resultant temperatures. Ideally, in high ambient temps, high gross weight, particularly on less than 1 hour turns; you should taxi at 15kts maximum and 10kts for turns. Save your tyres as you never know when they might let you down
Joined: Jul 2006
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From: Somewhere over the rainbow
Its is funny the forth right opinion on here, wrong as most of it is. Its got nothing to do with the nose gear. The issue affects all 'heavy' jets, the higher the weight the higher the tyre stress and resultant temperatures. Ideally, in high ambient temps, high gross weight, particularly on less than 1 hour turns; you should taxi at 15kts maximum and 10kts for turns. Save your tyres as you never know when they might let you down
Joined: Apr 2011
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From: SEQ
Its is funny the forth right opinion on here, wrong as most of it is. Its got nothing to do with the nose gear. The issue affects all 'heavy' jets, the higher the weight the higher the tyre stress and resultant temperatures. Ideally, in high ambient temps, high gross weight, particularly on less than 1 hour turns; you should taxi at 15kts maximum and 10kts for turns. Save your tyres as you never know when they might let you down
Once again, the logic leaves a bit to be desired.
Firstly, to taxi at such speeds would require multiple brake applications or you to ride the brakes to limit the speed to 15kts. Now we ALL know that brake wear in modern jets is based on number of applications and not whether the application is heavy or light braking. All of which would cause a large increase in brake temperature, more of an issue on a short turn around, and have little effect on tyre wear.
Do you realise that even at Max LDG Weight, and A320 will accelerate from 0-30kts without the application of any power above idle?
Secondly and probably more important and techincally correct is the Manufacturer's recommendation to allow the aircraft to accelerate to 30kts in a straight line..... as already stated above.
That being said, you are perfectly correct if your aim during taxi is to milk loggable flight hour, piss off any other operator taxiing behind you being forced to ride his brakes.
Joined: Jan 2014
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From: N5109.2W10.5
Originally Posted by Dogma 
See OP #1. If the restriction does not apply to a heavy NEO, why do you think it is a tyre problem?
Its is funny the forth right opinion on here, wrong as most of it is. Its got nothing to do with the nose gear. The issue affects all 'heavy' jets, the higher the weight the higher the tyre stress and resultant temperatures.
