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Asiana 214--poor weather might have prevented this accident 7/8/2013 5:33:25 AM
Asiana flight # 214 in San Francisco might not have crashed if weather had been poor. Asiana Flight #214 left Seoul South Korea Sunday with 291 passengers and 16 crewmembers. With the destination San Francisco International Airport, the big Boeing approached over San Francisco Bay nearly eleven hours later. The PF, or Pilot Flying in flyboy lingo, was an experienced aviator with more than 10,000 hours in jets, but only 43 hours logged in the 777. It was also his first ever landing at SFO. Weather was CAVU, more pilot jargon meaning Clear And Visibility Unlimited. In other words, weather was no factor.
It’s always easy to speculate on the cause, or causes of an aircraft accident: pilot fatigue, inexperience, missed details, passed over checklist items, the list goes on and on. From appearances, and from where I sit 3,000 miles away in the comfort of my home office, here’s my personal speculation on the crash of flight #214. I don’t know. I was never in the cockpit of anything that big and heavy. Never had the responsibility for 300 other souls after flying across that much water, for that many hours into an airport where I’d never landed before. So this is pure speculation, and I hope something else replaces it with hard data. But I suspect the approach over water with that heavy airplane, in clear conditions, by a pilot with all those jet hours led both pilots in the front office down the path of complacency.
Depending on how much fuel was packed into it on takeoff, and how long it’s been in the air, the 777 lands, typically, at around 300,000 pounds. That’s not only a lot of weight, it’s a lot of momentum. Modern turbofan engines are very efficient, very durable and extremely dependable. Feed jet engines like the two Pratt & Whitneys on the 777 fuel and air and they will run for a very long time with little or no maintenance. But jet engines also have their quirks, and one of them is that they take a while to ‘spool up.’ There’s a lag time from pushing the throttles forward to engine response. In the family car, which weighs a ton, two at most, the piston engine responds instantly. Mash the gas pedal and the power is there right away. Not so in a jet engine. Push power forward and the big turbine winds up to speed, often taking several seconds to reach needed power. Meanwhile a pilot has 300,000 pounds of metal descending perhaps a bit more quickly than he or she might prefer and a lag time in arresting that descent. Flight 214′s pilot had not flown into SFO before. The attempted landing on Sunday to runway 28 Left was over water for the last several miles. It was what pilots refer to as a visual approach, in other words, an approach without the use of instrument landing equipment, either ILS or radar. Runways always offer a guide called VASI, or Visual Approach Slope Indicator, a kind of light signal that shows pilots their position on an imaginary ‘glide slope’ to the runway’s end. But any approach over open water can be tricky. Water can distort a pilot’s depth perception by eliminating motion cues, its flat surface, especially on a windless day, giving no hint of forward movement relative to surroundings.
So we have pilot wearing a 300,000 pound airplane on his back, landing at a new field for the first time, with very little time logged in that particular aircraft type. He’s flown over a lot of water already, is likely fatigued, nervous as any pilot in training would be, and descending over yet more water. The descent rate is too high, the PNF, Pilot Not Flying, tries to add power to correct it, the engines start spooling up, but not nearly fast enough to stop the descent, and the aircraft lands short of the runway.
Only speculation, as I say. But my guess is that if the weather had been crummy, thus requiring an instrument approach, and if the PNF had been on the controls with the rookie pilot, and if the PF’s view was inside the cockpit instead of staring at a body of water, the landing would have been uneventful. I feel bad for the poor pilot. His life is ruined, at least for a while, and the memory of his final approach into SFO will haunt him forever.
