Originally Posted by
Bleve
I've had both 'report the runway in sight' and 'report the traffic in sight'. The motive of ATC in either case is to reduce their workload by shifting the burden of ensuring separation to you. But my job is to fly the aircraft, their job is to ensure separation. Why would I want to increase my workload and hence operational risk by doing their job for them (particularly when jetlagged after a long flight [into SFO!])? You could do the dance of reporting field/traffic in sight, then declining the visual approach clearance, but that just adds unnecessary R/T clutter to the airways. Much simpler to not report visual or field/traffic in sight in the first place (even if you are).
Those motives (to shift responsibility) don't apply to this case. The issuance of a visual approach by ATC if traffic ahead is reported in sight is true if that traffic is on approach to the same runway as you are. The controller can't assign a visual approach to a runway based only on having traffic in sight that's on approach to another, which was the situation here; UAL was on approach for 28R. You'll notice that ATC didn't clear Cathay for a visual approach when he confirmed he had visual contact with UAL. Cathay's clearance remained to fly a 310 heading to intercept the LOC for 28L and was never amended until much later when the offer for a visual approach came after the intercept was blown and it had all gone pear-shaped. The controller retained responsibility for the in-trail separation for the aircraft to their respective runways.
After confirming they had the traffic in sight, the "maintain visual separation" instruction Cathay received and acknowledged is an instruction that reiterates the US regulation that applies to both IFR and VFR traffic in VMC conditions, even under positive control, to see and avoid other traffic at all times. Obviously, this is critical at SFO with converging vectors to intercept the final courses of simultaneous approaches separated laterally by only 750'. Cathay's burden of responsibility was to intercept the LOC and to maintain visual separation from the parallel traffic. By regulation, even if that traffic hadn't been pointed out or Cathay hadn't spotted them and confirmed, in those VMC conditions and despite being on an IFR flight plan under positive control, looking-for and avoiding other traffic is a pilot responsibility that can't be shifted to the controller.
If in U.S. it's a mistake to believe that just because one is on an IFR flight plan and/or equipped with TCAS there is no burden of responsibility to maintain a visual traffic watch when prevailing conditions permit. It rested with Cathay as they were blowing through the LOC to wind up underneath UAL, one they had previously acknowledged after having them in sight, and not linked in any way to the the issuance of a visual approach. The visual approach clearance came later in an effort to salvage their arrival and only after Cathay was asked if they could proceed using one, they weren't assigned one as you describe or for the reason you've stated. The motive behind ATC's visual approach offer to Cathay was to allow them to sidestep back over to the runway 28L if they were able, at that point the only approach option left.
I'm wondering from the statements in your post, when you're flying into SFO in a similar situation and conditions as the Cathay flight in question, vectored to intercept the LOC 28L, when parallel traffic on approach for 28R is pointed out to you do you claim they aren't sight even when they are because you're fearful doing so will illicit a visual approach clearance? Or is everyone heads-down eyes inside, believing there's no responsibility to visually acquire traffic pointed out that will be soon be in very close proximity when everyone is lined-up correctly, and to avoid if necessary, banking solely on ATC and TCAS? I'm asking because at SFO this parallel approach situation separated by less than 1000' is routine and I was assuming that everyone involved during those ops was being super-vigilant looking-for and maintaining visual contact with the parallel traffic. I operate frequently into SFO long-haul from points in Asia and Europe on those approaches, and never found myself too tired or overloaded to look outside for traffic or the runway.
If the attitude that seeks to abrogate responsibility is part of a corporate culture and there's a misunderstanding of SFO ops/US regs it may serve to explain to a degree how this crew may have ended up underneath UAL despite the clearances to intercept a LOC and maintain visual separation were acknowledged and read back, but not followed.