Jetblue Airbus blows tires/ EVAC at Sacramento
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No doubt there will be the usual deluge of -ve A posts shortly, however the clue to
"And should the anti-skid prevent a landing with locked brakes?"
is in the terminology "PARKING BRAKE ON"
does your cars handbrake engage the ABS??
"And should the anti-skid prevent a landing with locked brakes?"
is in the terminology "PARKING BRAKE ON"
does your cars handbrake engage the ABS??
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"does your cars handbrake engage the ABS"
I don't think that this is a good analogy - in a car the normal brakes are hydraulic whereas the handbrake is usually independant and mechanical.
In aircraft I have worked on in the past, the handbrake puts inputs into the same servo valves as the foot brakes - which is also controlled by the anti-skid computer.
If I recall - although this is not directly connected - on the BAC1-11 you could (if you really were so inclined) land with the foot brakes already depressed prior to touch down as the brakes would be held off until spin-up. I have not heard of anyone trying it though
So, I had assumed that modern technology would have provided some similar protection - but clearly not.
In aircraft I have worked on in the past, the handbrake puts inputs into the same servo valves as the foot brakes - which is also controlled by the anti-skid computer.
If I recall - although this is not directly connected - on the BAC1-11 you could (if you really were so inclined) land with the foot brakes already depressed prior to touch down as the brakes would be held off until spin-up. I have not heard of anyone trying it though
So, I had assumed that modern technology would have provided some similar protection - but clearly not.
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I don't think that this is a good analogy
So just when would you "knowingly" apply the parking brake then?
OR,
If you were to be an an operator, when do think it would say, on your pre landing checks, brakes check, ...... , parking brake, OFF?
WELL?
PS sorry DILIGAF.
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So just when would you "knowingly" apply the parking brake then?
I do not understand your sarcasm. The NTSB have reported that the parking brake was set prior to landing. Now this was either set by mistake or there was a technical fault of some sort. So my question was related to whether there was some sort of protection on the Airbus - it seems from another poster that there is protection on Boeings 
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"And should the anti-skid prevent a landing with locked brakes?"
is in the terminology "PARKING BRAKE ON"
is in the terminology "PARKING BRAKE ON"
Adding a line of code simple as: an engine turning + no weight on wheels + park brake = output of what ever alarm, bell, banger, clanger, or whatever bitch'n betty statement you would prefer.
VFD
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I can't add much to the NTSB preliminary report, but I here is my theory from what I've heard.
Does this sound plausible?
PM (Capt) doing multiple tasks in a high workload environment.
PF (FO) calls for Flaps - does not get them as expected (PM had unintentionally selected parking brake instead of flaps.)
PF calls for Flaps a second time.
PF because of delay getting flaps in - now needs to go down and slow down in a hurry - wants to use full speedbrakes, so...
PF disconnects autopilot - while holding the Emergency Cancel button to keep the A/P disconnect from sounding. (Not SOP.)
Emergency Cancel for routine A/P disconnect actually cancels Parking Brake On ECAM by sheer happenstance.
Both miss green Parking Brake On on the status section on lower display unit. (Maybe it should be amber.)
That's my best guess based on what little I've heard around the hangar.
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Does this sound plausible?
PM (Capt) doing multiple tasks in a high workload environment.
PF (FO) calls for Flaps - does not get them as expected (PM had unintentionally selected parking brake instead of flaps.)
PF calls for Flaps a second time.
PF because of delay getting flaps in - now needs to go down and slow down in a hurry - wants to use full speedbrakes, so...
PF disconnects autopilot - while holding the Emergency Cancel button to keep the A/P disconnect from sounding. (Not SOP.)
Emergency Cancel for routine A/P disconnect actually cancels Parking Brake On ECAM by sheer happenstance.
Both miss green Parking Brake On on the status section on lower display unit. (Maybe it should be amber.)
That's my best guess based on what little I've heard around the hangar.
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Those at Boeing don't. Why do those at Airbus?
Probably due to the same design decsion in both cases: allow the action (WOW switch may be broken) but give warning and/or obvious feedback to the pilot, and let them override/correct it - after all, the pilot will know whether or not they are on the ground.
