TCAS procedures

[Capn Bloggs]

Fair enough, 1500fpm is 1500fpm regardless of bank. As for looking out the window, that is exactly why TCAS was created - because looking out the window doesn't work.

[Wizofoz]

CB,

Notice you still haven't quoted what yout manual actually instructs you yo do in response to an R/A.

Yes, TCAS is a boon and a suplement to the obvious limitations of see and avoid.

It is NOT a catch-all panecea to be used as a total solution. An R/A means every other source of avoidence has failed.

Too many are under the impression they are not allowed to avoid a collision unless the magic box tells them to do so.

[Capn Bloggs]

Wiz,

Make sense please. Earlier you asked:

Kindly state the 737 FCOM reccomendation as to how to react to a T/A.

To which I replied "read your FCTM".

Now you state:

Notice you still haven't quoted what yout manual actually instructs you yo do in response to an R/A.

You never asked me that previously, but in response, my answer, IAW with my FCOM, is "I'll do whatever the RA instructs me to"!

"If possible" I will attempt to get a visual but I can assure you that as PF that won't be likely. I will be glued to the PFD to make sure I nail whatever it is I have to nail to comply with the RA. Nor do I expect my PM to screech "you're going the "wrong way" or "pull harder" based on what he can see out the window.

As for secretly turning the TCAS to T/A ONLY in the SIM, great stunt.

[Sciolistes]

that it was expressly forbidden to manoeuvere based upon a TA only.

There seems to be some misinterpretation of the FCTM. Manoeuvring solely on a TA means using the traffic display as your sole guide. The 737 QRH recall procedure is quite clear. If in receipt of a TA establish visual contact and manoeuvre if needed.

For an RA the procedure is to maintain the planned track (turns and all) unless visual contact means you have to alter your planned track to avoid.

This means that one does not manoeuvre in response to a TA only. Neither does one do anything but what the RA says. Unless in both cases you can see the traffic and it is clear that there is a greater risk if the current flightpath is maintained.

[camber]

CB, A very generic statement, regarding bank. For example, B777 Traffic Avoidance - RA states:

" ....(after disengaging autopilot and autothrottle etc)...Follow the planned lateral flight path, unless visual contact with the conflicting traffic require other action."

So, if you have LNAV engaged, and are approaching a turn point/commencing turn, and have a RA, continue the planned lateral track, during the RA, unless visual cues clearly dictate otherwise.

How many crews have practised that scenario in the SIM I wonder?

[Wizofoz]

Sorry, CB, a typo.

I quoted my 777 FCOM Maneouvres section on proper reaction to a T/A

You had quoted a line that supposedly contradicted me, saying don't manoeuvre soley on the basis of a T/A. I never said you should. I said MY procedures (which contain the identical warning) say to aquire the target visually, using the TCAS as a guide, and maneouvre if required.

Does your say different?

If not, why did you selectivley quote-mine the line that seemed to contradict me (not that it actually did) whilst not being forthcoming with the actual procedure, with which I concur?

[p51guy]

So you will refuse to look out of your windscreen if you have an RA? Good luck if it glitches that day. Leaving everything to the automation is a very dangerous procedure. Following TCAS is standard procedure but looking out the window is still allowed. One day at 4300 ft on a 2,ooo fpm rate of climb I was told level at 4,500 oposite direction traffic 12 o'clock 4,700 one mile. Our 737 couldn't level without possible injuries so I looked out the window and it was clear so expedited the climb to go above traffic. The controller then said your traffic passed below you at 4,500 ft. Sometimes you have to take care of yourself, not rely on automation or controller last minute input. This was before TCAS. TA's and RA's are great safety enhancements if we don't throw out the old look out the window collision avoidance.

[p51guy]

As far as TA's we had a helicopter who didn't quite shut his transponder down landing on a yaught on an approach path to MIA on RW 30. Hundreds of ac got the TA alert until they shut if off finally. Everybody did the approach ignoring the TA. It had no altitude info so just sent a TA because he went off mode "C.