Originally Posted by
BlunderBus
A lot of airlines refuse to allow NIGHT visual approaches. SFO has its own circumstances but why not tune the ILS ..accept the visual and fly loc/gs guidance anyway? I’d use ILS guidance on any night visual. Why not use all resources? I think the controllers screwed him around as heard in the verbal exchanges. Swearing on air is ‘verbotten’also.
Pretty crappy effort from both sides.
Originally Posted by
Capn Bloggs
It's all on the first few pages of the thread:
1. The Quiet Bridge Visual arrival is not aligned with the ILS (post #90);
2. The QB requires aircraft to visually self-separate with the adjacent aircraft down final because the runways are so close together; independent approaches (vis or ILS) can't be flown;
3. LH SOPs do not permit visual self-separation.
BB, adding to what CB has said;
Both the QB Visual for 28R and the Tip Toe Visual for 28L require some electronic guidance. They're both charted/published and if you check them out you'll see what's required. Both their respective ILS's are depicted. If you study them you'll find:
28L (TIp Toe Visual) is a straight-in approach. Tuning/ IDing the ILS freq is mandatory since the LOC is the primary lateral guidance source (not merely a backup) that you're required and cleared to intercept and track inbound to the runway. You can fly it coupled all the way and use the GS which is set at a lower path angle than 28R's. The 28L LOC must be working for this Visual.
28R (QB Visual), as mentioned, has a 6 degree offset based off the SFO VOR (095R) until the Bridge @ 6 DME SFO, so both must be working. However, you do indeed tune the 28R ILS because that will be a source to establish your straight-in alignment and path once inside the Bridge. GS for 28R has the higher path angle. The slight maneuver to align oneself straight-in for 28R inside 6 DME is more clearly depicted on some plates than others. Inside 6 the Loc is just about alive.
So both Visuals require operating ground-based NAV; the SFO VOR DME and the 28L LOC with a requirement for use. ATC clearance for one of these charted Visual Approaches requires one to follow the plate, and for neither does "Cleared for the QB or TT Visual" mean establishing oneself inbound visually or by following another aircraft to the same runway. There is the expectation that inside 6 DME both will track their respective LOCs. By this time they will have had each other in sight for miles while tracking electronic guidance designed to produce the gentle 6 degree convergence. The speed assignments will include the directive for the aircraft slightly aft to not overtake the one ahead.
"Maintain visual separation"....this clearance means exactly what It says, and 'Maintain" does not equate to "Visually establish and maintain separation". Establishment of separation between the aircraft is accomplished by the design layout of the electronic guidance paths and each aircraft flying that electronic guidance as cleared. For the final-turn intercepts ATC will establish through speed control and alt assignment a slight fore/aft stagger plus high-side./low-side vertical separation. The glide paths have slightly different slopes. After establishing inbound, If both aircraft follow their respective clearances and charted electronic guidance, separation continues to be maintained without doing anything except to visually monitor the other aircraft in case someone F's-up by drifting off-course or off-speed.
The only aspect of these Visuals that differs from an instrument approach is, if on the QB inside of 6 DME, the necessity of turning a bit further left in order to ease into the groove/intercept the 28R Loc for the last few miles.
Most likely some ,if not all, of the LH crew had flown the very same Visuals during the daytime (when they normally arrive when on schedule) and were in no way surprised they were in use. They were handcuffed by their SOPs. Bummer.