A/C Braking System Redesign
Hi Guys.
You may or may not be aware of the accident in Manchester last Tuesday, when an Aer Arann ATR was approaching stand and failed to stop at its stop bar. It continued for several feet beyond it resulting in a collision with ground equipment. It would appear that the driver had lost all hydraulic pressure and was unable to apply any pressure to the brakes. Photos on the R & N forum would suggest that the a/c suffered a total and catastrophic loss of hydraulic pressure.
If that proves to be the cause of the accident, is there not a case for aircraft brakes to be redesigned so that hydraulic pressure keeps the brakes in the off position so that in the event that total hydraulic pressure is lost, the brakes would automatically engage?.
The ATR braking system would appear to have quite a lot of redundancy built in and has tried to cover all eventualities – two systems Blue and Green, DC elec pump in the event of failure of the AC system, cross feed from one to the other, accumulators in the event of the loss of pressure and an emergency brake.
None of the above will work if the hydraulic line fractures at or close to the calipers.
Cheers