NZ 831 grounded (A320)

[On Track]

Don't know if any A320 gurus can enlighten me without getting too complicated...

At this moment I was to be pax on NZ 831 from Queenstown to Sydney but the flight has been cancelled because of a technical issue.

The captain kindly came into the departure lounge to tell us in person that there was an issue in the preflighting. Apparently a computer which interrogates all the systems showed a fault in a back-up braking system, which couldn't be rectified on the spot.

Would someone mind explaining to me in general terms how the brakes on these aircraft work??

Incidentally Air NZ, the NZ Customs Service and the duty free shop handled everything very smoothly once the no-go decision was made.

[Fragnasty]

The brakes, when applied, slow the rotation of the wheels on the main landing gear. This stops the aircraft. It's not unlike the brakes on a car.

[qtn]

Bwahahahahahahahahahahahahah

[Metro man]

There is a back up braking system which will give seven brake applications from a reserve of hydraulic pressure should the main system fail. The pressure is stored in what is called an accumulator and released on demand.

The accumulator is kept pressurised when the engine driven pump is operating, or can be pressurised via an electric pump when the engines are shut down.

From memory the back up system is a no go item as, should the main system fail you would have no brakes.

[AerocatS2A]

Yes, and if the main brakes were to fail while they had an abort at Queenstown you'd have another "shotover jet" incident reminiscent of the Ansett NZ days .

[On Track]

Thanks Metro man and Aerocat.