Thanks Singapore!

When we pushed back from the gate in Minneapolis, the visibility at San Francisco International Airport was 1/4 mile in fog.  The forecast for our scheduled 11:40 AM arrival was scattered clouds and six miles visibility; a typical morning in San Francisco.  I told my First Officer they would probably be shooting visual approaches by the time we got there; most likely the FMS Bridge Visual to 28R.  As it turned out, I was being optimistic.  One hour out of San Francisco, Salt Lake Center asked if we were Category III capable.  When we checked in with Oakland Center, the controller asked: "Delta 2305, what's the lowest RVR (Runway Visual Range) that you can accept?"  We told him we needed 600 RVR---and then set ourselves up for a Category III ILS (auto-land) approach to runway 28R.  We also checked to see that the weather at our alternate (Sacramento) was holding steady at clear and better than ten miles visibility.  You know; just in case. . .

When Oakland Center handed us off to Norcal Approach, the SFO ATIS was broadcasting 100' scattered, 1/2 mile visibility, and calm winds.  Since the visibility was improving, I briefly considered "bugging" for a standard ILS.  Then Southwest Airlines checked in on the frequency and was told to expect to hold for Oakland.  I decided it was probably a good idea to just fly what we had briefed.  The ATIS was calling it "scattered," but from our position we could see that San Francisco Bay was completely covered with fog, maybe three hundred feet thick, from the touchdown zone of Runway 28R, all the way to the Oakland Hills!

Norcal Approach had us join the localizer just outside of DUMBA.  Before handing us off to SFO Tower, the controller told us to look for a Singapore 777 that was joining the localizer six miles in front of us.  It was easy to spot.  Triple-sevens tend to stand out---even at six miles!  "San Francisco Tower, Delta 2305 is with you for Two-Eight Right."  "Roger Delta, maintain 170 to AXMUL, you're six miles in trail of a heavy triple-seven, caution wake turbulence, cleared to land Two-Eight Right, touchdown zone RVR is better than 6000."

We were pretty heavy.  In fact, our MD-90 was just under it's max landing weight of 142,000 pounds.  To hold 170 knots on the glideslope we had the flaps set at 23 degrees, the maximum prior to extending the landing gear, and still the jet wanted to accelerate. We were gaining on the triple-seven; but only slightly.  It would probably be touching down when we crossed AXMUL, so our spacing was still good.

Crossing AXMUL, I called:  "Gear down, flaps 40 on the green, landing checklist."  I set the airspeed bug to our final approach speed, and watched for the triple-seven to disappear in the fog.  It didn't.  Moments later it's nose was pointed skyward on a missed approach---climbing like crazy!  About what you would expect from a jet that is light on fuel, and has over 100,000 pounds of thrust on each engine!  After a brief delay, Singapore called the missed approach.  SFO Tower told them to fly runway heading, and climb to 4,000 feet. . .

As we were descending through 1000 feet, United Airlines checked in on the frequency---asking why Singapore had gone around.  The controller replied that there was a layer of clouds 100' above the touchdown zone, and several airplanes had gone around in the past thirty minutes.  Along about here I was thinking:  With 50' bugged on the radar altimeter for the Category III approach, we'll probably be under the layer.  The triple-seven is a BIG airplane---and the flight deck sits pretty high. . .  Maybe it's time for the little guy to shine!  Passing through 300' the fog began to clear.  Seriously!  It started with swirls on both sides of the runway that spread to the center line---a valley in the fog for us to fly through---we were in the clear all the way to touchdown!  As we exited the runway, the First Officer said:  "I guess that guy's wake, and the heat from his engines, cleared that stuff out.  Thanks Singapore!"

Flight 2305, Gate 42, San Francisco International Airport.

 
In the hotel lobby, one hour later, another crew from Big D was checking in.  The captain asked:  "Where did you guys come in from?"  I replied:  "Minneapolis."  "Were you guys on 2305?"  "Yes."  The first officer had a weird look on his face:  "And you made it in?"  Now it was my turn to have a weird look on my face:  "Yeah, why do you ask?  Did you guys divert?"  The captain replied:  "No, we're San Jose guys.  We followed you out of Minneapolis, but we heard they weren't getting in to San Francisco."  I laughed, and then told them about Singapore.  The San Jose captain smiled and said:  "The mighty triple-seven had to go around; but the lowly MD-90 made it in!  Well done!"