TAA_Airbus From Australia, joined Nov 1999, 726 posts, RR: 0
Reply 1, posted (11 years 8 months 2 weeks 5 days 7 hours ago) and read 2021 times:
I dunno JETPILOT.
If they didnt collide, wouldnt it say that TCAS did its job?
They pump out RAs about 20 seconds before anything will happen, so in that 20 seconds, should you follow them, its still going to be a near miss. But as long as you didnt hit, Id say TCAS did its job.
But I havent read about this incident, and thus cant say to much about it.
Kaitak From Ireland, joined Aug 1999, 12293 posts, RR: 35
Reply 6, posted (11 years 8 months 2 weeks 2 days 14 hours ago) and read 1852 times:
I believe the 747-400D was flying from Haneda to Osaka and the DC10 (also JAL) was on a flight from Pusan to Narita; they came within a hair's breadth of each other - I've heard 30' mentioned, which for two very large airliners travelling at a very high closing speed is incredibly close.
AM From Mexico, joined Oct 1999, 589 posts, RR: 2
Reply 7, posted (11 years 8 months 2 weeks 2 days 13 hours ago) and read 1849 times:
Talking about TCAS, can it perform some kind of emergency maneuver to try to avoid conflicting traffic all by itself? Maybe an autopilot override? Or is emergency traffic avoidance always performed by the crew following TCAS's advisories either by autopilot or manual inputs?
"... for there you have been and there you will long to return."
Almbluzman From United States of America, joined Dec 1999, 182 posts, RR: 1
Reply 8, posted (11 years 8 months 1 week 2 days 18 hours ago) and read 1781 times:
does anyone think that reduced vertical separation might have had a big impact on these incidents? also, what effect might these incident's have on the proposed reduction of vertical separation minimums in the u.s.?
Klaus From Germany, joined Jul 2001, 21353 posts, RR: 54
Reply 9, posted (11 years 8 months 1 week 2 days 16 hours ago) and read 1780 times:
AM: Talking about TCAS, can it perform some kind of emergency maneuver to try to avoid conflicting traffic all by itself?
Not as far as I know. The actual course change must still be done by the pilots.
Almbluzman: does anyone think that reduced vertical separation might have had a big impact on these incidents? also, what effect might these incident's have on the proposed reduction of vertical separation minimums in the u.s.?
I´m not an expert, but by looking at the principle I would think that reduced vertical separation would actually decrease the probability of a conflict since the same number of planes would be distributed among a greater number of flight levels.
On the other hand, a deviation from the assigned flight level would be more critical. And that would include the risk involved with evasive action in case a conflict should still occur.
But with increased positioning precision and adapted ATC procedures I would still expect the overall risk to go down rather than up.
B747skipper From , joined Dec 1969, posts, RR:
Reply 10, posted (11 years 8 months 1 week 2 days 3 hours ago) and read 1756 times:
Just a word here...
I believe, from having a look at official near miss (and collision) reports, that there is more problems with LATERAL rather than VERTICAL separation... except in a few climb/or descent scenarios...
In the new RVSM airspace above FL290, vertical separation is reduced to 1,000 feet... In the original altimeter designs, I doubt that there was much more error above FL290... if compared between FL270/280, or FL290/300...
Maybe it was the case in the higher FL370 or 390 levels... no much change...
I fly in RVSM and non-RVSM airspace... I never notice more level separation or discrepancies in the non-RVSM airspace... separation always seems to be 900 to 1100 feet vertically from "potential" traffic on our TCAS equipment...
I would worry more about LATERAL separation, personally...
Saintsman From United Kingdom, joined Mar 2002, 2065 posts, RR: 2
Reply 11, posted (11 years 8 months 1 week 1 day 14 hours ago) and read 1744 times:
With regard to the TCAS putting an input to the autopilot. Autopilots don't like sudden large inputs because it causes them to trip out. An alert from the TCAS would by nature call for a large manoever in order to avoid a collision, so the last thing you would want in that situation is for your autopilot to disconnect and leave you with 'nothing'.