Air Canada 759 Near-Miss at SFO on July 7, 2017

Update: as of Jan. 14, 2018, there have been 3 incidents in the past 6 months of airliners lining up for the wrong runway at SFO.

On July 7, 2017 an Air Canada jet nearly landed on a busy taxiway, Charlie, and had to do a go-around at SFO. It missed another airliner on the taxiway by less than 100′, and other airliners behind the first.

There’s three problems with that:

  1. the pilot was cleared to land, not cleared for a low approach over taxiways
  2. Low approaches over taxiways can only be approved at 500′ above ground. See “3−10−10. ALTITUDE RESTRICTED LOW APPROACH”: “A low approach with an altitude restriction of not less than 500 feet above the airport may be authorized except over an aircraft in takeoff position or a departure aircraft. Do not clear aircraft for restricted altitude low approaches over personnel unless airport authorities have advised these personnel that the approaches will be conducted. Advise the approaching aircraft of the location of applicable ground traffic, personnel, or equipment.”
  3. jet wash at TOGA power can be destructive, especially against the flight controls of the airplanes on the ground.

The go-around is a normal procedure, and in fact your only 2 options are landing or go-around, so that wasn’t a problem, or even unusual, as some reporters wrote.

At this time we’re fairly sure the pilot and copilot couldn’t identify the correct runway, but the question is why not?

Some possibilities:

Category Risk Factor
Aeromedical fatigue, as the flight was late at night, especially considering the departure was from the East Coast
Aeromedical QUIET BRIDGE VISUAL RWY 28L/R approach was flown using FMS, possibly abstracting the flight path in a confusing manner than a relatively simple ILS
Aeromedical approach was visual at night, much riskier than VFR Day. I believe European airlines don’t allow this.
Facilities Runway 28L was closed for construction and the normal lights turned off, changing the expected landing sight picture
Facilities taxiway lighting might be LED, thus appearing white instead of blue (taxiway edge) or green (taxiway center) at a distance
Navigation ILS is often inoperative at SFO (likely the actual cause of 2013 Asiana Flight 214 accident)
Controller tower/ATC is either not adequately engaged, or needs more radar or cameras. It’s great that the UA pilot radioed, “Where’s this guy going? He’s on the taxiway.” but it would have been even better had Tower noticed that first.

The reason for the current excellent airline safety record is having scheduled flights from Point A to Point B, which are known in advance (ie. scheduled.) However, SFO is an unsafe airport that has several surprises for pilots:

  1. old US airports like SFO were built with parallel runways too close together for safe parallel IFR operations
  2. SFO is between 2 mountain ranges (San Bruno and Diablo)
  3. SFO is next to a “black hole” (SF Bay is not visible at night)
  4. increased navigation risk with continual ILS problems
  5. now add construction and lighting changes.

SFO is more of an obstacle course than a safe airport at this point. The first 3 problems are inherent in SFO’s location, but the last 2 are airport-management induced.

The Air Canada cockpit voice recorder was not stopped, and eventually recorded over this time period as the NTSB did not learn of the incident for 2 days. Ironically, the most valuable information is probably the routine cockpit conversation about the approach setup 3 miles out, (the why?), not the last-second go-around scramble.

The NTSB will probably try to estimate the distance. It should be interesting how they do this calculation because of how small the times and distances are. Normally aircraft tracks are not calculated to the foot!

Also of PR interest is that the aviation community waited for more data on the loss of separation distances before commenting, while the press and flying public were quick to outrage.

One forum poster called this “closing ranks,” which is not a fair criticism since airplanes often approach to the “wrong runway” (daily examples are circle-to-land procedures and Tower change of parallel runway instructions) and overfly other planes in the airport area.

In fact, Tower prefers transiting VFR airplanes overfly the center of the airport because then they know precisely where you are, versus interfering with landing or departing paths.

Disclaimer: I hold a commercial airplane licence and have flown Bay Tours through the SFO airspace, but I am not an airline pilot.

latimes.com: Investigators probing how Air Canada pilots’ mistakes led to near-disaster at San Francisco airport

avweb.com: Disaster Averted! Or Not?
pprune.org: Near miss with 5 airliners waiting for T/O on taxiway “C” in SFO!
mercurynews.com: Exclusive: SFO near miss might have triggered ‘greatest aviation disaster in history’, HN
NTSB Issues Investigative Update on San Francisco Airport Near Miss
Air Canada disappeared off SFO air traffic radar equipment for 12 seconds before near-disaster, NTSB says
avweb.com: Air Canada Flight Misses By Four Feet?
SFO Landing Incident Prompts Focus on Pilot Monitoring, CRM

Third Landing Mixup At SFO

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