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From time to time I land at Wellington Airport in an A-320.

The runway has sea at either end and is 2,081m (6,827ft) long.

There's never been a problem but I find landing there a bit nerve wracking (the frequent high winds in the area means just getting the plane over the fence is sometimes a little more exciting that most would prefer).

I imagine that getting the wheels onto the runway as soon as possible is a priority so you can start braking but I wonder in a flat out emergency how much runway does an A-320 need (full of passengers/cargo but not much fuel) to stop if nothing else matters but stopping ?

EDIT: I meant to say I do appreciate that wet/dry runway and head wind strength would influence this quite strongly but I'm just looking a ballpark figure.

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    $\begingroup$ Just to clarify, are you a pilot or a passenger in this context? $\endgroup$ – Greg Hewgill Sep 11 '15 at 0:39
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    $\begingroup$ You mean Emergency landing or stop the process when taking off like the latest BA2276 case? $\endgroup$ – Him Sep 11 '15 at 1:07
  • $\begingroup$ @GregHewgill : I'm a passenger and an admirer of the pilots who land at Wellington ;-) $\endgroup$ – glaucon Sep 11 '15 at 1:58
  • $\begingroup$ @Him I'm interested in landings. The question was sparked by a landing the other night when we seemed to be a surprisingly long way down the runway before we got the wheels on the ground and then there was a good deal of brake/reverse thrust noise. It left me wondering how far down the runway could you be and still not end up in the sea. On Sunday night there was a good strong southerly so I guess that changes the nature of thing as well. $\endgroup$ – glaucon Sep 11 '15 at 2:03
  • $\begingroup$ Every flight I have been on has used thrust reversal and it makes a huge amount of noise. How much traffic does this airport get. I live here in Denver about 15 minutes away from the airport, and I so wish I could go plane spotting here. An airplane lands like every 45 seconds. $\endgroup$ – Ethan Sep 11 '15 at 2:18
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Airbus's charts for the A320 suggest that it requires approximately 4,500ft for a sea-level landing at typical landing weight. I've extracted this from this Airbus document (the A320 landing chart is on page 49), which is admittedly more of a promotional brochure than an operating manual.

Wellington's runway is 5,955 ft between thresholds, and 6,827ft overall, so there is some room for error. However, depending on the nature of the 'flat-out emergency' a pilot may approach faster implying a longer landing roll, or choose a firm landing and significant abuse of the brakes to shorten it.

Christchurch and Auckland airports both offer much longer runways at 10,787ft and 11,925ft respectively, so I'd speculate that a pilot faced with a known problem with brakes or thrust reversers might elect to divert there if range permitted.

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    $\begingroup$ From QRH, via this document, question 73: A320 – CONFIGURATION FULL, LANDING DISTANCE WITHOUT AUTOBRAKE Actual Landing Distance, GW 130,000, Dry: 2,920 feet This is the ALR determined during flight tests, security and failures coefficients apply. Note that landing distance is usually measured from a height of 50 ft to the wheels stop. $\endgroup$ – mins Sep 11 '15 at 12:26
  • $\begingroup$ The Airubs web also has a document titled “A320 for airport planning” which is a technical document and it does have landing field length chart, which confirms 4500 ft at sea level at MLW for A320-21x (CFM56 engines) and a little less for A320-23x (IAE V2500 engines). The older edition also had approach speed graph, but the current one only has the value for MLW. $\endgroup$ – Jan Hudec Sep 11 '15 at 12:48
  • $\begingroup$ Note, that landing distance calculations don't consider thrust reversers. The difference between engine types is likely due to difference in idle thrust rather than efficiency of reversers. So problem with reversers is not an issue. Problem with brakes would probably warrant diversion. $\endgroup$ – Jan Hudec Sep 11 '15 at 12:52
  • $\begingroup$ Related details showing the complexity of distance calculation: In flight landing performance. Landing distances for A320 extracted from Airbus OLD with landing distances for different conditions, and using two definitions of landing distance: Operational Landing Distance (OLD) and Factored OLD (FOLD). $\endgroup$ – mins Sep 11 '15 at 13:27

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