TCAS saved the day in SFO this past Saturday

[IBPilot]

A UA B777 came close to hitting a Cessna 182 when it was departing for PEK!!

http://news.blogs.cnn.com/2010/03/30/fe ... /?hpt=Sbin

FROM THE ARTICLE:
A UA B777 departing SFO for PEK on Saturday March 27 almost hit a Cessna 182 when the two planes came within 200-300 feet of eachother.

The UA pilots were climbing through 1,100 feet when SFO TWR warned them of a small plane at their 1 o'clock position. Immediately following the warming, the TCAS system on board the UA B777 sounded. The UA F/O leveled the aircraft and established a straight attitude and just as they did so, the Cessna 182 passed 200-300 feet above them.

The NTSB lanched an investigation Tuesday

> Thank goodness for TCAS. There are still obvious questions as to who was to blame for this. ATC, the Cessna 182 pilot or the UA pilots. My guess is either the Cessna Pilot (for flying that low and close to the active departure runway) or SFO ATC. Shouldn't they be watching....

Regards

[Captain_Canuck]

YIKES!!!

[Troubleshot]

Or if I tried to write the headline in cpl-atc's style....AIR TRAFFIC CONTROLLERS TRY AND MURDER PILOTS AND PASSENGERS

[iflyforpie]

Or if I tried to write the headline in cpl-atc's style....AIR TRAFFIC CONTROLLERS TRY AND MURDER PILOTS AND PASSENGERS

No, it was the RCMP's fault somehow...

[Main Gear]

Here is a link to the ATC tapes:

http://www.avweb.com/podcast/podcast/Au ... ml?kw=self

[Liquid Charlie]

Thank goodness for TCAS.

I have to wonder if the TCAS made any difference at that altitude and config except for giving them possibly a traffic warning -- good chance RA mode was still inhibited --

[rigpiggy]

I'm pretty sure TCAS only inhibits below 400 radalt, I may be wrong though

[nwesterntown]

Here is a link to the ATC tapes:

http://www.avweb.com/podcast/podcast/Au ... ml?kw=self

Be nice to hear the rest of that conversation.......

[Liquid Charlie]

Be nice to hear the rest of that conversation.......

Indeed from the sound of the first officer all they had time for was to blink - she was a little lost for words

[cyeg66]

You'd think they'd have the Chief fly over the threshold of the runway and not the end where 700,000 lbs is pointing at you skyward. Sheesh. Tower seemed a little lackadaisical. Didn't seem to think that might scare the ever lovin' crap out of the heavy crew, whom incidentally, is a little too busy during the takeoff phase to be worrying about a light GA in their vicinity. Poor, in my mind. I'd like to hear the conversation (one way, no doubt) that ensued on the other freq. Situation similar to the ACA 777 takeoff from Narita, recently.

[rigpiggy]

CPL_ATC, now you stepped in it!

[PostmasterGeneral]

That's crazy I wonder what was said on the other frequency after the fact...

[IFRATC]

I haven't heard the tape yet, but any of you fly over YSO inbound for YYZ on the 23/24 runway config on a nice VFR day??? The amount of targets lurking between YKZ and YSO is atonishing. More often than ever before have I begun to level traffic off above the bedpost altitudes because of VFR targets. Mind you I am not talking to them so traffic info is passed to crews with unverfied altitude readouts on VFR targets. I have had many a crew thank me for that as they blow by some schmuck out there not realizing the volume of traffic moving through that corridor.
The scary part is when we are too busy to be passing out all this traffic info, and are not able to operate with intrem altitudes prior to the bedpost. I will say that we make every effort possible to pass on known and unknown targets through busy arrival corridors. Your workload is high at this point, and your eyes are not necessarily focused out the window. Enough reason for me...Many moons ago I too was in your shoes. I know what it feels like to know about traffic lurking out there but not necessarily seeing it....

IFRATC

[Wilbur]

It must be a cover up by corrupt airline pilots and ATC. That's why they wanted a discreet frequency or a phone call rather than staying on the freq that would be recorded. Probably part of some plot by power mad controllers and airline pilots. After all, everyone knows the ranks of ATC are filled with ego maniac tyrants who get off telling others what they are allowed to do and where they can go; right cpl ATC?

[cyeg66]

The radar tapes would be most telling of the situation. What was the 182's trajectory vis-a-vis the heavy: perpendicular track, almost parallel with slight convergence? If the heavy planned a quicker initial climb rate than the 182's pilot had anticipated, it could have turned out a little squeakier than even he expected. Sure, there's visual passage but a 777 isn't meant to be played chicken with. Maybe the 182 driver is a thrill seeker. Probably coulda taken a nice picture from his perspective .

[flyinhigh]

No biggie here. The crew was advised of the traffic, and should have been mentally prepared to disregard the TCAS squawking at them in the background. It's not like TCAS alerts are a rarity in close proximity to an airport. VFR separation is not IFR separation, and TCAS is calibrated for IFR sep losses, so nobody should be surprised if the box barked a bit.

Neither the controller nor the 182 pilot sounded the least bit concerned about the potential for real conflict, so I suspect the 777 crew overreacted. EDITED

I would love to invite you into my cockpit flying into these busy airports anytime. We have had one into newyork not to long ago. King Air had us insite, we didn't have him so he thought what the hell I'll get closer. Needless to say, if we the Crew don't have the other aircraft insite, were not going to hang around to find out if he truely did see us to avert us.

The fact you think no big deal. WOW, tell ya what you jump into that 182 and i'll come by at 250kts fully loaded to within 200 feet and tell me than its no biggy.

[teacher]

I've always hated that instruction. "maintain visual seperation", seriously, just give us a heading so we can avoid hitting each other!!

I had a similar thing happen in Boston, light aircraft told to maintain seperation, needless to say we got at TCAS RA.

[Braun]

WE do give headings. But apparently some times pilots don't want to follow instructions. I.E. Tool of the day thread.

Agreed on the "maintain visual separation" in this case, it's stupid!

[CYXDSTUD]

The controller had asked the 182 driver to pass behind the heavy but to me it sounded like the 182 pilot replied "they'll pass behind us".

[402_pilot]

LOL so i guess that discrete frequency wasn't so discrete after all.

[Nark]

Much like a required "hold short" clearance must be read back, so must a "Maintain visual separation" in class Bravo airspace (ie SFO, SAN LAX etc..

I use ADS-B, which is like TCAS on steroids. I get TA all the time departing and arriving, but I trust Mk I eyeball more than the screen as I've seen a number of ghost indications.

If the UA crew was startled, then someone was lying when they said they'd maintain visual...

[teacher]

Hey "Braun", didn't mean it as a slight against ATC at all. I'm just not a fan of placing my trust and safety in anybody I can't "see" but claims to see me. Especially a weekend warrior.

[Intentional Left Bank]

If the UA crew was startled, then someone was lying when they said they'd maintain visual...

Not necessarily. To the Champ, who agreed to visual separation, spacing may have been perfectly adequate in his mind. To a VFR pilot, adequate spacing may mean something different than to the 777 pilot, or to the 777's TCAS. It doesn't sound like 777 drivers were ever advised of the traffic by the tower.

Note also that voice advisories are inhibited below 500 AGL, RAs are inhibited to 1100 AGL on departure, and DESCEND RAs are inhibited to 1200 AGL in the climb. So while the TCAS would have annunciated TRAFFIC above 500 AGL, it couldn't provide an RA due to altitude inhibit, and once the altitude permitted an RA, the only RA possible was DESCEND, which would then be immediately inhibited. Additionally, while the 777 would be reducing its climb rate to 1000 fpm at 1000 AGL to accelerate and retract the flaps, it would require a substantial pushover to stop the climb and initiate descent.

[Company Itin]

Don't sound like either pilot in the 777 was overly impressed.

I doubt it would have been an RA. Probably a TA. I don't think the small A/C would have the required transponder to activate an RA. Still not a fun situation.

If theres anyway to find out what was said on the "discrete" frequency, please post it. Otherwise I"m sure it would go like this.

"Go a head united 889"
"beeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeep"
"roger, sorry, have a good flight"
"beep you"
*radio silence*

[Pratt X 3]

I doubt it would have been an RA. Probably a TA. I don't think the small A/C would have the required transponder to activate an RA.

TCAS will generate an RA if the other aircraft has a transponder with Mode C operating. I believe you are thinking about 2 Mode S transponder equipped aircraft co-ordinating their RA's. As the smaller aircraft was operating in SFO's Class B airspace, it is required to have a Mode C transponder (FAR 91.131 http://rgl.faa.gov/Regulatory_and_Guida ... enDocument).