Monday, July 8, 2013

SFO Crash: Human Factors or Swiss Cheese?


Two days ago an Asiana Boeing 777 crashed into the runway at San Fransico’s International airport. The National Transportation Safety Board is planning to interview all four pilots who were onboard the Boeing 777 jet that crashed. Asiana Airlines says the pilot in control of the plane had little experience flying it and was landing one for the first time at that airport. Now this is not uncommon, but there is a coaching pilot that is ready to take control if there is a problem. We are still waiting for more information to come forward but, my question is this. Where was this coaching pilot? 

Asiana Boeing 777 that crash landed at SFO
"A lot is focused on the crew’s experience, their training, how they worked together, crew resource management, the way that they communicate and how they divvy up their responsibilities. We’re looking into all of those things right now," NTSB Chairman Deborah Hersman told Fox News.

First HOLE in the Swiss Cheese:

Asiana spokeswoman Lee Hyomin told the Associated Press Monday that Lee Gang-guk was trying to get used to the 777 during Saturday's crash landing. She said the pilot had nearly 10,000 hours flying other planes, including the Boeing 747, but had only 43 hours on the 777. I would submit that this fact was only a factor in the crash and that other factors were present. 

Second HOLE in the Swiss Cheese:

Four seconds before impact, a “stick shaker” – a device that emits an oral and physical warning to the crew that the plane is about to stall – sounded off, Hersman said.The crew then asked to abort the landing and make another attempt 1.5 seconds before impact. The minute the shaker engaged, why wasn’t there immediate corrective action?

Asiana Plane doused with foam to prevent fire rekindle
Third HOLE in the Swiss Cheese

There was also a shut down of a key pilot navigational aid. Earlier Sunday, Hersman said on CBS' "Face the Nation" that the glide slope system is a ground-based aid that helps pilots stay on course while landing and it has been shut down at the San Francisco airport since June. The pilots, however, were notified before the crash that the system wasn't available.


"The pilots would have had to rely solely on visual cues to fly the proper glide path to the runway, and not have had available to them the electronic information that they typically have even in good weather at most major airports," said Captain Chesley "Sully" Sullenberger, who crash landed a plane in New York's Hudson River in 2009, told a CBS news affiliate, according to Reuters.

The Swiss Cheese Model with
Process Control added to fill the holes.

I am sure we will learn more about this crash. It is important to understand that there was a clear trail of “Out of Control” condition present. As I have mentioned in previous blogs, it is possible to close up the holes in the "Swiss Cheese Model." Were there procedures on "training" a new pilot? Should the airport use that runway with ILS not working? Should there have been better "control" on the approach by the experienced pilots on board. It is clear that procedures need to be examined. Policy on training needs to be reviewed. I am sure we will learn more that may add additional holes in the Cheese! NOTE: Please see post "Safety Through Control" in this blog, May 13, 2012. 

NOTE: This and other crashes will be discussed at specific control workshops at the QA/SMS Symposium being held at the Coronado Hotel DisneyWorld Florida Sept 29-Oct 2, 2013. Goto: www.dtiatlanta.com click on symposium. 






1 comment:

  1. Additional information since the post: It was discovered that the "Auto Throttle" was not on during landing. Again, this is another hole in the cheese! The Auto Throttle engage light would have been pulsing...no one noticed it?

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