Pressing the A320 autobrake buttons.

[lfbb]

Hello every one, I’m just about to finish my enrout training on the A320 and my last instructor is picking on me when I press the autobrake button, he says that these buttons need to be pressed and held for a few seconds so the aircraft acknowledge the ON/OFF command…and that if I press it and let it go right away the system might understand that I pressed it y mistake and will disregar the command..... this is the second time someone tells me that, first on the simulator training and now on the enrout train, has anyone heard that before?
EDITED
Thanks!

[Airbus_a321]

no need to press and hold for a few seconds - but should be pressed firmly to assure AUTOBRAKE is armed.
it was told: once in the past the pushbutton switch was obviously pressed very, very softly and as a result (only) the AUTO/BRK ON light came on, but the system was still not armed.

[PantLoad]

Autobrake Button

lfbb,

Ok, since you say you're doing so well in your training, I have an 'Oral' question for you: Right after pressing the autobrake button, how would you definitively determine if the autobrake system has been activated...and that the level of autobrake activated is the level you've selected?

By the way, have a look at Airbus FCOM 3.03.16 Page 3. I think you'll find that your instructor (and Airbus) still know more about this than you do, despite how well you think you're doing in your training.

PantLoad

[lfbb]

Ok guys take it easy please, I know I sound too confidante, and a top gun by the words above, when I wrote that I was afraid people felt that way by reading that, but I wanted it to sound more like a joke and because English is faraway from being my native language (as you can see) I guess you’ve got me wrong… anyway I posted this question exactly because I found out too weird that two experienced pilots told me the same thing about the autobrake push buttons, so there must be something there… but I just could not find it, I thought it could be some misinterpretation of the FCOM that has been passed around the airline, so I wanted to check with other pilots, just like you PantLoad. I’m sorry if you felt uncomfortable with the way I expressed myself, that was not the idea. Anyway the FCOM page that you mentioned has the following note:
“Note : If, on very long runways, the flight crew anticipates that braking will not be needed, use of the autobrake is not necessary.
Firmly press the appropriate pushbutton, according to the runway length and condition, and check that the related ON light comes on.”

Ok, so firmly does not mean pressing it for 2 to 3 seconds…. And the answer to your question is… check the wheel page on the ECAM and look for the autobrake indication…
Best regards.

[PantLoad]

You Passed...

Yes, you're correct! You passed the 'Oral' exam!

Remember the secret to getting through any kind of training: Cooperate/Graduate....


PantLoad

[lfbb]

Originally Posted by PantLoad

Remember the secret to getting through any kind of training: Cooperate/Graduate....


PantLoad

You bet!

[EMER_CANC]

Hi,

Yes, there is a valid reason for keeping the AUTOBRK pb depressed for a few seconds. I am unsure if recent MODS to the BSCU have rectified the Command and Monitor system on the Airbus. However, you will find your answers here:

http://www.fomento.es/NR/rdonlyres/8...1998_019_A.pdf

Cheers,

EC

[Engine overtemp]

It was issued as an OEB (Operations Engineering Bulletin) from Airbus in 1998 and the relevant bit stated...

1) If autobrake is to be used at landing

Before landing gear extension

-Appropriate autobrake mode...... Select

Press the autobrake pushbutton firmly for at least 1 second to ensure the autobrake system is properly armed

The investigation into the incident that EMER_CANC mentions showed that "The loss of autobrake and of the normal braking system was due to a disagreement within the BSCU following a quick action of the autobrake mode pushbutton"

I believe the OEB has now been cancelled though!

[el !]

Originally Posted by EMER_CANC

Hi,
Yes, there is a valid reason for keeping the AUTOBRK pb depressed for a few seconds. I am unsure if recent MODS to the BSCU have rectified the Command and Monitor system on the Airbus. However, you will find your answers here:
http://www.fomento.es/NR/rdonlyres/8...1998_019_A.pdf
Cheers,
EC

This is a Well Done accident report. Thank you EMER_CANC.

[Dream Land]

Good question Ifbb, good flying.

[black diamond]

Give the pb a good firm, positive push. I've seen it illuminate blue then not engage after touchdown because the button was not pushed positively enough.

[MrBernoulli]

"....illuminate blue then not engage....."

Airbus! I sometimes wonder where their designers graduated. This is basic stuff and they can't get it right.

[Frank Poncherello]

Hiya, another point to mention,........

If that is all the training captains are correcting you on, then your doing a fine job. You will find that even a couple of years into the job, and with a few Sims under the belt, there are still some minor debrief points such as this one that get mentioned. After all, they gotta have something to debrief you on.

I agree though, a quick check on the ECAM wheel page should tell ya if it is selected.

Pats on the back all round,.....

FP

[el !]

Originally Posted by MrBernoulli

"....illuminate blue then not engage....."

Airbus! I sometimes wonder where their designers graduated. This is basic stuff and they can't get it right.

In fairness, it appears that just after the incident, the issue was addressed and fixed. And, only presses of a certain duration, rather than just short presses, were able to trigger the problem.
So probably, the long press is still taught as a matter or oral tradition and best practice.
I personally found more disturbing that after the TAO 10% of flying A320 were found with an inoperative emergency braking system.