Overnight Update on Asiana 214

Why it matters that the crew (apparently) said "Go around!" just before the crash.

Papi Indications.gif

As mentioned earlier, first-round information about an airplane crash is often inaccurate. That is proving to be the case this time too. Here are some second-round reports, a day and a half after the "landing short" crash of Asiana flight 214 at the San Francisco airport:

- I mentioned yesterday that the glide-slope guidance from the Instrument Landing System (ILS) on San Francisco's runway 28L was out of service, thus denying the Asiana pilots a dashboard indication of the proper rate of descent. That remains true.

-I also mentioned early reports that the PAPI system - Precision Approach Path Indicator, a group of lights alongside the runway to guide pilots on the proper path of descent -- was not working. Those are PAPIs illustrated above, from here. Two red and two white lights mean you're on the right path. Any more whites, and you're too high. Any more reds, and you're too low. It now appears that those reports were wrong, and that the lights were still working during the plane's descent. They were listed as "out of service" shortly after the crash, presumably becaused they were damaged by the impact itself.

- I quoted a veteran commercial pilot as saying the members of the Asiana crew had a combined total of 10,000 flying hours. That appears not to be true: the captain is said to have some 10,000 hours himself, and the others were experienced too.

- On the other hand, it appears that the captain, at least, had only minimal experience in the Boeing 777, the plane involved in the crash. Many reports said he had only 43 hours' flying time in a 777 -- not very much, with not many landings. More on this below.

- According to all accounts I've seen of yesterday's NTSB press conference, just a second or two before impact someone in the cockpit said "Go around!" This is the command for aborting a landing attempt if pilots don't like the way it is shaping up, or if there is an obstruction on the runway or some other reason not to try to land. In a go-around the crew applies full power, they make some other adjustments, and they guide the plane to climb as rapidly as possible away from the runway where it was about to touch down. Then they get set up for another approach. This report about a too-late attempt at a go-around matches some passengers' recollections that they could hear the engines powering up just before impact. If it proves true, naturally it shifts attention away from engine failure (you can't "go around" if you have no power) and similar explanations of the accident. It focuses more attention on why the crew was following a descent path that they later realized would not lead to a safe landing.

On what all this means by way of explanation, I give you the views of another airline pilot who wrote in last night. As with some previous notes, I'm not going to explain all the flying lingo. You will get the main point.
I've been a captain on the B-777 for over 13 years, 10,000 in the B-777, and a check captain for more than 10 of those years for one of the three major US carriers. I have no interest in public attention, but the reporting on the TV and radio has been atrociously inaccurate, including by "experienced airline pilots" who have never flown the aircraft. Aircraft are not all interchangeable and skills are sometimes poorly transferred - like one of our pilots who shutdown the "outboards" to save fuel, but was on a two engine aircraft after leaving a four engine aircraft.

Several issues not yet reported widely and are significant:

Visual landings to a runway with a displaced threshold can be misleading. The displacements exist for a variety of reasons - obstructions, noise sensitivity (look at 34L at Narita), or others. The seawall may be the reason for 28L at SFO; the reasons are not explained.

More significantly, the B-777 is a flying simulator. The dozens of military and commercial aircraft I have flown will pitch up with thrust added for any number of reasons. This particularly true for aircraft with engines hanging from pylons below the wings. The DC-10 crash in Iowa was partially controlled with thrust from engines 1 and 3 by the flight instructor sitting in the flight engineer middle  seat. The B-777 is programmed to cancel any aerodynamic or thrust vector caused by thrust addition or reduction; Pitch is unchanged. If the pilot flying is used to an aircraft pitching up when additional thrust is applied, he will be sorely disappointed.

There has been considerable opinion differences between the THRUST  vs PITCH crowds in aviation. After overlapping careers, 40 years as a Certified Flight Instructor, 20 years as a Navy pilot, and 35 years as a commercial pilot, the argument continues. If the pilot just raised the nose and was already low and slow, he was on the "backside of the power curve". Raising the nose only lowered the tail further and there was insufficient "ground effect" due in part to the height difference of the runway and the bay as well as the insufficient speed. Thrust was the only way to save this poorly executed approach.

When the engines are "spooled up" with landing flaps and landing gear extended, the engine response should be very good. But the Autothrottle system can be turned off, removing a lower limit of airspeed eliminating automatic throttle increase when slow.

The Boeing engineers are today's equivalents of the "rocket scientist", both whom have experienced a declination in status between the space shuttle accidents and the B-787 multi-year delays and battery problems. Be careful of dedicated experts.

New guy, bad behavior transfer, no copilot help from multiple copilots (could be cultural, deference to the captain), displaced threshold, inoperative glideslope transmitter, inoperative VASI lights, some backup flight systems possibly selected off, minimal initial operating experience (line operational instruction with a check pilot), and other factors will come out of this NTSB investigation.

Some more in the queue, but this is it for now.