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ratso
28th Dec 2008, 01:27
When entering a CTAF and there is VFR aircraft with a transponder on in the CTAF ....do you guys who fly VIRGIN and JSTAR monitor the VFR guy on your TCAS?

Defenestrator
28th Dec 2008, 01:31
Dunno about the DJ and Jestar guys but we monitor EVERYTHING that comes up on TCAS regardless of the airspace.

D

andrewmizzi
28th Dec 2008, 02:18
Nah, they turn it off and close their eyes. :p (Dumb question, dumb answer).

Could you elaborate a little more on your question and describe what you're getting at, maybe with an example of something that's happened to you? Is this based from the Ballina CTAF thread?

BlinkC182
28th Dec 2008, 02:42
ratso would you monitor it if you had TCAS?

I sure hope the answer would be a positive YES!
:ugh:

RENURPP
28th Dec 2008, 05:58
Dont be to hard on him.

I am aware of at least one Jet RPT Captain that regularly asked asked a light aircraft to turn their SSR off as he was concerned about getting an RA within the circuit.

Glass houses and stones?

Ratso

I dont work for either company you mentioned, but TCAS is very helpful in providing situational awareness. It shouldn't be used independantly for seperation it should prompt some investigation if it a return pops up and wasn't expected.

ratso
28th Dec 2008, 06:18
There are a few OLDER VFR pilots who fly into ballina regularly ....and they have often asked me do you think the jets know approximately where I am if my transponder is on.
My answer has always been ...OF COURSE THEY DO....but these guys wanted an opinion on this web site. Most of them are not computer savy and are quite fasinated by this web site.
Majority of them have said the last thing they want is for a PAX jet fully loaded to initiate a go around just because of their cessna getting in the road.
I guess after this I will get a few more questions to ask for them.
Communication I guess is what its all about.

waren9
28th Dec 2008, 06:37
Yes, TCAS gives us a very good idea where you are (relative direction and distance) for sighting, and your altitude relative to ours. It also tells us if you're climbing or descending.

Do us all a favour (including yourself) and keep it on. RA's (resolution advisories) are inhibited below about 900' anyway so theres not much to gain and quite a bit to lose if you switch yours off.

Hope this helps.

woftam
28th Dec 2008, 07:53
What IDIOT would want them to turn it off !!!!!! :ugh: If you get an RA buddy it is for a very good reason!!!! :mad:

ratso
28th Dec 2008, 09:27
Thanks for your reply.....no these guys WILL keep their transponders on.

Also thanks to the others for taking the time to reply.

AerocatS2A
28th Dec 2008, 09:38
Ratso, TCAS will display transponder equipped traffic within the display range set by the pilots. It will show a symbol that indicates approximate position, relative altitude, and whether it is level, or climbing/descending at 500 fpm or more. There are different symbols that indicate the threat level of the traffic with aural warnings and avoidance advice given when the threat level is high. As an example, a quick glance at the TCAS may show that the traffic is front left, 800 feet above, climbing at a minimum of 500 fpm, and no immediate threat. It is NOT like a radar display and is NOT capable of showing an accurate position, but it does provide information that can be very helpful in aiding a visual sighting of the traffic.

So please tell your friends to turn the transponder on, the advantages far outweigh the disadvantage of nuisance warnings.

RENURPP
28th Dec 2008, 11:18
WOFTAM
What IDIOT would want them to turn it off !!!!!! If you get an RA buddy it is for a very good reason!!!!

I agree, my post was in response to this commentNah, they turn it off and close their eyes. (Dumb question, dumb answer).


and this one I sure hope the answer would be a positive YES!

The initial question was not stupid at all. Some people, even those flying jets do some strange things.

yowie
28th Dec 2008, 12:35
Just to re-iterate the backward one, never ever ever turn off your transponder, but more so never ever ever rely on interpreting seperation based upon them:ouch: Radial/bearing/vector/distance is THE only way to separate, unless it is an RA situation!:ugh: And by the way, us so called jet jockeys DO NOT have right of way, anywhere, period:ok:

89 steps to heaven
28th Dec 2008, 19:32
Also be aware that TCAS is not perfect. At times I have given traffic info based on what I can see on my display, but get a reply from the pilot that they don't have it on TCAS yet.

There also can be more than one other aircraft in the area, not all with transponders.

TCAS is a good tool, but it is only one out of many tools that pilots use.

Capcom
28th Dec 2008, 21:35
Agreed 89'

There are more than a few examples of an RPT (717's particularly early on), where on-board ACAS would not see a lightie if the lightie was below and on a reciprocal track. The theory is that it is possibly caused by lightie TXPDR aerials being on the belly (where they necessarily need to be), and therefore perhaps the engine and associated electrical shielding in the front end of the aircraft provides a block. This may be why this signal shadow occasionally occurs particularly on reciprocal (or thereabouts) tracks!

ACAS is very very good, of that there is no doubt, but it is not a 100% anti-collision prophylactic!!

woftam
28th Dec 2008, 21:58
RENURPP, sorry mate, I wasn't having a go at you . I just couldn't believe a "Jet RPT Captain" would be so stupid. It may have appeared that I was shooting the messenger. Not at all mate. :ok: I was commenting on the "Jet RPT Captain" who should know better!! . :ugh:
I also agree with most of the posts here regarding not relying solely on TCAS for separation. It IS however a great aid in a busy CTAF environment and transponder use must be encouraged not discouraged !!!
PLEASE KEEP YOUR TRANSPONDERS "ON" AT ALL TIMES .
And ratso, GREAT question mate and good debate that has followed. This is a very important issue for everyone that operates in these environments.
Stay safe !!

Mick.B
28th Dec 2008, 23:26
Nah, they turn it off and close their eyes. (Dumb question, dumb answer).


Settle down Andrew. If you dont ask you dont know. No need for that stuff here. Especially from a student pilot. :=

Mstr Caution
29th Dec 2008, 05:32
Jet Jocks change procedures too.

Not that many years ago TCAS was selected to "TA only" to avoid "nuisance" alerts & approved by company procedures.

Such examples were parallel runway ops (Sydney) or high density traffic environments.

TCAS accuracy has improved over time & therefore the use of RA at all times has come with this improved TCAS performance.

MC

psycho joe
30th Dec 2008, 01:13
There are a few OLDER VFR pilots who fly into ballina regularly ....and they have often asked me do you think the jets know approximately where I am if my transponder is on.


I hope I'm waaay wrong here but to me this almost could be interpreted as your friends asking whether having a working mode c transponder precludes them from having to make a radio call to establish separation.

TCAS is a great tool but it can't give us your callsign, accurate position, intentions and lateral tracking. So if in doubt about separation push that switch under your thumb and make a call, even if your calls aren't particularly refined. Thats the only accurate way to know where you are and what you're doing.

ratso
30th Dec 2008, 22:11
I did not want to add any more to this thread as there have been a lot of very intelligent and informative replies. But I had to respond to this.

PSYCHO ol mate relax .........They all talk on the radio and give their position with their transponder ON.

Thanks for the comment anyway

Have a geat new year.