From Capt Bogs:
Watching the coverage about Asiana Flight 214 on Fox news last night was painful. So much so that I feel compelled to hit the internet with my take.
Since it has been a long time, I will first bore you with my Bona Fides. I am a retired pilot with over 20000 hours of flight time. I flew the C-130 for the Air Force for about 20 years, then retired. Then flew for a regional carrier until United Air Lines hired me. I was an engineer and later a flight instructor on the DC-8 and DC-10. Then I flew the Boeing 747 as a copilot, upgrading to Captain on the 727. Went on to fly the Airbus A-320, and moved to the 767/757 fleet, returning to the Airbus after 9-11 forced the airline to reduce their active fleet, all as a Captain.
Enough history. Now to yesterday’s accident.
The normal way a flight from the Far East is vectored to SFO is over the City itself at or above 10000 ft, then flying out over the bay, descending as the plane passes the airport. At this time the copilot has by far the best view of the situation as he can see the airport and judge the descent, the lateral displacement from the runways, and the distance from the end of the runway. With the flight instrumentation on the 777, when the runway is selected on the automatic flight instrumentation, the Instrument Landing System (ILS) will give the flying pilot a visual indication of the glide slope he will want to follow. After the plane goes underneath the glide slope, or when it looks like they will transition below the glide slope as they turn toward the airport, the flying pilot will bring the plane to the right to set them up to intercept the extended center line of the runway. The plane should intercept the runway centerline below the glide slope. They will then fly up the centerline until they descend toward the runway on the glide slope, configured with landing flaps and landing gear, engines spooled up producing power, ready to go around, fully in control of their fate. Their descent angle will be 3%, losing 300 feet every nautical mile. This is called a stable approach; required by the FAA as well as all certificated airlines, the safest way to approach a landing runway.
The following is my reconstruction of the accident aircraft’s flight path, with no hard facts but the experience of having been based in San Francisco flying to the Far East for years.
The flight path for Asiana 214 probably started the same way. High over the city, out over the bay, descending. The captain is probably flying the jet, at this point hand-flying but maybe on the auopilot. The captain is at a disadvantage, because the runways are hard to see cross-cockpit, and Korean way does not lend itself to ask for help if you are in command. There are a lot of things going on: Air Traffic Control (ATC) may be asking him to shorten the approach, (This is the time of day when there are jets arriving from airports all over the far east.) he is perhaps too high and too fast, he needs to get his craft slowed down so he can configure for landing (get the flaps and gear extended, there are speed limits for each extension) and worst of all he has no electronic clues as to his position from the runway. It is now that he has bad luck from the weather; if the weather was bad he would have had to have had electronic help but the good weather has given the airport the opportunity to do some maintenance on the ILS system, taking it off the air.
As the captain turns onto base leg, which is 90 degrees from the heading of the runway, he sees that he is in a little too close to the runways and he is not fully configured. He pulls the power off and raises the nose, bleeding off airspeed quickly. He drops the flaps as the jet slows and turns onto the centerline of the runway, releasing the nose down and allowing the airspeed to build. There are lights on the side of the runway, defining the glide path, and he sees that he is still above it. He now undergoes one of the problems of SFO. San Francisco is a special qualification airport due to the mountainous terrain in the area, but it is also one of those tricky airports. You approach the runways normally used by heavy jets from over the water; there are no visual cues to help with depth perception. As a result the spy-data-gathering instruments on the jets show that this airport has more unstabilized approaches than almost any other airport in America. Relying on what you see out the window is just not reliable. The captain looks outside, thinks he is high, pulls the power back to get to what he thinks is the right height but is in fact too low.
Approach lights slide below the jet, close enough to touch. With the power off, airspeed bleeding down, and no altitude to spare, the captain jams the power levers forward and pulls the nose up, trying to stretch his glide to the runway. Instead, he enters into the beginning of a stall, the wings waggling, the nose up and the tail of the jet settling into the sea wall. Asiana flight 214 is below the glide slope, engines not spooled up, configured correctly but not flying. Their fate is in the hands of gravity and drag.
With the plane hitting the seawall short of runway 28L, we are no longer into speculation. We can see the debris. The jet tracks onto the runway, shedding parts in a straight line. The empennage sheds off; the vertical stabilizer going one way and both horizontal stabilizers falling off the other. As the jet settles down onto the part of the runway short of the displaced threshold,the ground grinds off the rest of the tail all the way to the rear pressure bulkhead,popping it off and and pulling a couple of young women out of the plane and onto the ground, killing them. The jet slams down, shearing off the nose gear, and then bounces back into the air. One of the impacts breaks the main gears off. This smashes the jet engines off, one of them spinning off to the side and the other nestling into the right side of the fuselage. The jet slides off the runway,the nose tracking to the right even as the plane skids to the left of the runway.
As the jet comes to rest, the flight attendants spring into action. Screaming at the passengers to release their seat belts and get out, the flight attendants see the fire on the right side of the plane. They direct the passengers to use the exits on the left side. A completely successful evacuation ensues with the jet emptied within a couple of minutes despite the fact that the emergency was completely unexpected and unbriefed. The cabin crew, unlike the cockpit crew, reacted professionally even after an all night, energy draining flight. Well done.
Not so well done for Fox news. They have a light plane pilot who anchors their weekday AM programing who was completely out of his depth on this incident. After a wandering, unfocused commentary he got stuck on “air pockets” (no such thing) and “microbursts” (a severe and dangerous weather condition associated with convective weather.) Hint: When there are no thunderstorms there are no microbursts. The mountains west of the field may produce some turbulence, but the weather had already been reported as clear with light winds. He really had no worthwhile inputs relative to a huge high performance jet going into a difficult airport.
The first guest with any good inputs was a retired NTSB investigator. They gave him about 45 seconds and went into commercial. He eventually got back on for most of a segment that was very informative. Finally someone who knew what he was talking about.
For some reason all the networks seem to think that people who have no flying background are able to describe accurately things an airplane does. Last night the best things the bystanders had to say was that the jet was coming in very nose-high. They did not know how to describe this, but we got the picture. Unfortunately, along with this nugget, we also got the “airplane cartwheeled” and slid down the runway upside down. No, no, no! Clearly, there were two wings still attached to the body as the jet sat there burning on the side of the runway. No way it tumbled. We were then subjected to this “slid upside down” comment for half the evening. A guest finally said that there was no way that this had happened, and after a couple of more upside downs in the summaries it finally went away.
A passenger said her plane hit some turbulence on short final as it landed on 28R. She had some useful pictures. But, turbulence that her pilot did not comment on to his passengers in a fairly light turboprop will not usually even be felt in a 700,000 pound jet. This may have been what Mr. Scott glommed onto when he brought up his microbursts.
They also had a “former Naval Aviator” making comments. At first I thought he was just a a shill for Boeing, as most of his comments were about what a great and safe plane Boeing had made, and how safe it was for us to fly. Yeah. All true. Not informative. His comments comparing Airbus planes to Boeing just showed his ignorance (777’s are fly-by-wire, too) and the rest of what he had to say on Saturday was a waste of air time. Oddly enough, his appearances on the Sunday morning shows were excellent, with cogent, informative comments that were right to the point. I guess we should never trust a squid on Saturday night. You never know what they have been consuming.
What Fox did extremely well Saturday was to pursue the numbers. Airlines are loath to talk about numbers until they have had a chance to triple check their rosters and passenger service computers. It is way too easy to not have everyone who is on the plane identified, or to have people who were checked in but who did not get on the flight as a passenger. This has improved since 9-11, but at the last moment they are more interested in getting the jet off the jetway and off into the air that being absolutely accurate with names and numbers, even though when something like this happens everyone thinks they ought to be perfect. Fox pursued every count at each hospital, pushed officials to tell what they knew and then followed up to make sure it was accurate. I’m not really sure why it is important, but it was something they did well.
Sunday morning was a lot better. Fox had people who had actually been into and out of SFO, they had the NTSB doing their stuff and grownups answering (and asking) cogent questions
At no time did anyone comment about the fire. Fortunately, the jet was almost out of go-juice when it impacted the ground. I’m sure there was almost nothing left when they landed. I know we were always short when we finally got home. ATC knew it, of course, and they made allowances for us and gave us unasked-for traffic preference. But Asaina had no weight in those still-intact wings. They sat there, inert, as the fuselage burned even though both engines, with lines conveying all those refined oil products from the wings into the engines, sat there unattached. One of the engines, the one which ended on the right side of the fuselage, burned a little, but it did not look like it burned through the skin of the plane.
Something burned into the fuselage, though.
All the way through.
After everyone got out. Remarkable.
- SFO ‘glide slope’ inoperable during Saturday’s crash (mercurynews.com)
- Pilots faced challenges landing in San Francisco (jsonline.com)
- Official: Asiana Flight Tried to Abort Landing (nation.time.com)
- Exclusive: ‘Wake Turbulence’ & Pilot Error Could Have Caused SFO Asiana Crash (breitbart.com)
- Possible clues emerge in Asiana Airlines flight 214 crash (syndicatednewsservices.com)
- Armchair air crash investigator (momav.me)
- My visual approach, and Asiana’s (blogs.law.harvard.edu)
- Pilots faced challenges landing in San Francisco (newsobserver.com)
- Survivor could see runway through hole in tail (news.terra.com)
- Possible clues emerge in Asiana Airlines flight 214 crash – CBS News (cbsnews.com)
Filed under: Aviation, Captain Bogs | Tagged: Air Traffic Control, Asiana Airlines, Far East, Instrument Landing System, National Transportation Safety Board, San Francisco, San Francisco International Airport, United Airlines |