Airbus A320 TCAS Abnormal Procedure
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Airbus A320 TCAS Abnormal Procedure
Hi all,
I am new at the Bus and trying to understand a few things. Do you know why one has to switch of the FDs on a TCAS Event? What happens with the Autothrust with the FDs switched of?
By the way, did you ever have a Resolution Advisory?
Thank you...
A.
I am new at the Bus and trying to understand a few things. Do you know why one has to switch of the FDs on a TCAS Event? What happens with the Autothrust with the FDs switched of?
By the way, did you ever have a Resolution Advisory?
Thank you...
A.
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Also, you switch off the FDs because you shouldn't have them on while delierately flying away from the flight path they are demending so, if you want some non FMGS flight path (eg following TCAS RA orders) then switch off the FDs. The speed bug will revert to selected at the current speed and the autothrust will go into speed mode to maintian that speed.
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Join Date: May 2006
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1. Have you ever tried to guess an intruders relative position based on a visual contact??- it is bloody hard to do, especially far out and a bit easier as target is closing in. Now, imagine doing the same thing at night...start by sorting out which is the red NAV light and which the green one, to find out the Track crossing angle.
2. After lessons learned of the Mid air collision with DHL/Russian you will anyway end up following your TCAS, no matter what ATC tells you and no matter where you spot this guy(he might still be in a shallow climb/dive which you will NOT pick up on a visual contact but TCAS is already computing, or you look at the WRONG one....)
3.So, only way to do it, is watch your TCAS, get a situational awareness from TCAS what the intruder is doing, especially at night and IMC
4. In VMC and far out, one of you might still go for a visual contact, but BOTH???
5.End up in a proper flown RA with both FDs OFF by PNF, thus A/THR in actual, selected SPD and no danger to fly into any other mode reversion due to not following FD commands
Wish you luck for your next RAs....and hope we don't meet too close in the air.
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assume you are flying level and you get RA to clb, if you do clb without putting your fds off A/T will power back till you hit vls 
at which point a lot of nasty thing happen
above given example is only one of many
I am sure you get the drift......with fds off A/T will be a slave to speed so one less thing to worry about. forget all the gizmos in front of you and concentrate only on your V/S and listen to the aural warning till you hear "clear of conflict"......least you end up upsetting the entire stack of...c's
at which point a lot of nasty thing happenabove given example is only one of many
I am sure you get the drift......with fds off A/T will be a slave to speed so one less thing to worry about. forget all the gizmos in front of you and concentrate only on your V/S and listen to the aural warning till you hear "clear of conflict"......least you end up upsetting the entire stack of...c's
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At Bangkok I had a RA once with another aircraft as we approached head on during descent (at about 200 knots indicated) by day in clear air to the I.F. 21 ILS.
The other skipper mustve been the same age as me: we just used the Rules Of the Air and both of us altered heading to the right. Saved having to go through a TCAS mad panic.
The other skipper mustve been the same age as me: we just used the Rules Of the Air and both of us altered heading to the right. Saved having to go through a TCAS mad panic.
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In panic one could have made a left turn when they actually wanted a right turn. Tupolev Flight BTS2937 is an example of a deviation of TCAS commands (they followed ATC instructions) and ended with deathof a lot of people. These days all modern aircraft is TCAS equipped but if pilots don't use it and prefer to use rules of the air which was used when aircraft was much much slower and lighter, why bother have TCAS?
Just follow the TCAS commands. Learn from other's mistakes.
Just follow the TCAS commands. Learn from other's mistakes.
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Some companies switch off the FDs at the first sign of traffic conflict - when TA is received. This is in order to be better prepared for what may turn into an RA so one less thing to do if the RA is received - just follow the V/S command.
ps Why cant Airbus modify this heap of cr*p and put it on the PFD like all modern aircraft. The A320 display is the same as that for the old DC9 and B737 when TCAS was first invented. Of course, I forgot, "not invented here in TLS"
ps Why cant Airbus modify this heap of cr*p and put it on the PFD like all modern aircraft. The A320 display is the same as that for the old DC9 and B737 when TCAS was first invented. Of course, I forgot, "not invented here in TLS"
