Monday, December 16, 2013

An Essay on S-A...

I think the pilot was simply creeped out. 

He was the pilot flying, and was responsible for control inputs during the leg from from Brazil to France on the evening of June 1st, 2009. He would shortly be the proximate cause of his Airbus A-330 descending, under full power, into the Atlantic Ocean. All 216 passengers and 12 crew members would die because of a simple breakdown in crew communication, coodination, and situational awareness. This would not be the first time these human factors would lead to the loss of an aircraft - nor the last. If you are a HEMS crew member understand that I write this to prevent you from having to share their fate. I mean no disrespect to those who lost their lives, instead I would like use what we can learn to prevent future mishaps.

There are many reasons that crew members fail to communicate effectively in flight. In the case of the very recent crash of an Asiana Airlines Boeing 777, investigators point to culture, or power-distance, which is the amount of deference paid to superiors by subordinates. There is usually someone on board an aircraft that is about to crash who knows a problem exists, but they don't speak up.

The fail to assert led to the worst air crash in the history of the world; the destruction of two Boeing 747 aircraft, and the loss of 583 lives. Read about it by clicking here...

A crew member practicing:                                                          

Inquiry - the act of seeking information to create understanding

Advocacy - the act of pleading a cause or course of action

Assertiveness - the act of speaking up for what you think is right.

can prevent a crash, but because no one rings a bell when a crash is avoided, the larger HEMS community doesn't know.

The Air France pilot had the aircraft set up to fly automatically through an area of persistent bad weather known as the inter-tropical convergence zone. In flight, a pitot-tube was blocked by freezing rain, and the aircraft's computers lost the airspeed input and changed modes.

The fly-by-wire flight control system switched from "normal law" to "alternate law" affecting how much a given movement of a side-stick controller will move a control surface, but the pilot flying didn't know this. He lost situational-awareness. That aircraft is so complex, and can have so many things happening at once with systems, that the pilot doesn't understand what is happening or why.

This pilot got creeped out; he had just flown through a patch of rough weather and an atmospheric phenomenon that created an unfamiliar smell in the cockpit.

Then he  did two things wrong. First, he reflexively pulled his side-stick all the way back. When we get scared in an aircraft, one of our instinctive responses is to climb. His excessive control-input made the aircraft climb, and slow down. and then descend.

As he saw that the aircraft was descending, he kept this full-aft stick input applied. He wanted to go UP, not down.  His second and more important failure was that he failed to announce what he thought was happening and what he was doing about it.  This failure robbed the other pilot on the flight deck of situational-awareness. The second pilot didn't know that the stick was all the way back or nose-up, and they were stalling the wings. They fell into the ocean with engines screaming, in a level attitude. The designers never imagined that a pilot would hold the stick all the way back, all the way to the water, without anyone else noticing.

The take-away on S-A...

1. Anytime you sense anything "different" about your aircraft, sound the alarm! "Hey we have a new sound, shimmy, vibration, smell..." 

2. Then, announce what you think the problem might be. An electrical fire? Loss of oil pressure on engine number two? Loss of hydraulic-boost? A blocked fuel pump inlet or the strong odor of fuel? Take your best guess.

3. Announce what your are doing about this new sensation. If you are adjusting a flight control, switching a switch, turning a knob, speeding up, slowing down, climbing, descending, whatever... Announce your actions!

The other pilot could see that they were descending, but as that aircraft is fly-by-wire versus fly-by-cable, and there is no linkage between the two side-stick controllers.  The other pilot was denied the information that would have been provided by an old-fashioned between-the-legs control wheel being pulled backwards into his gut.

You can read about this crash by clicking here...

You can watch a video about this crash here...

                                         Photo courtesy Shawn Griffin, former USAF Combat
                                         Camaraman, current USAF and civilian flight nurse

Crew coordination is each of us knowing what the others are doing, when, and why. I was on a flight with a new crew member in a Bell 206.  He elected to get ahead of the game by placing a blood-pressure cuff on a patient's arm while still in the ambulance. They took the patient outside of the ambulance to move him from the EMS stretcher onto our aircraft stretcher. The other crew member observed a blood pressure cuff on the patient's arm and assumed it belonged to EMS. He took it off and handed it away. When we were all in the aircraft, the medic said to the nurse, "damn, I put a cuff on this guy, I wonder what happened to it."

Crew coordination depends on practice and communication - before, during, and after a flight. Rehearsals in the aircraft, full-crew simulator training, table-top scenarios, "rock-drills," and of course post-flight after-action-review all contribute to good crew-coordination.

Using periods of time when the work load is light to prepare for high work load times is part of Air Medical Resource Management.

Cross-training, or understanding what other members of the team do, and why, helps with maintaining situational-awareness. I practiced an instrument approach recently, with a relatively new flight nurse sitting directly behind me in our Astar. He was able to see over my shoulder. I explained everything I was doing. He asked what indications I was looking for on the instrument displays. I mentioned the common mistake of having the display set up to show GPS information when intending to use information from the Instrument Landing System (ILS), and handed him my approach plate to look at while we flew. Is he going to be responsible for how I fly approaches?  No. But the more he understands about what I am doing the better.

Sometimes we don't speak up because we are new, and don't want to say something dumb. In the name of every brand-new crew member who has been killed in a helicopter crash, you must set that thought behind you.  There is no such thing as a dumb question in an aircraft.

One of the Asiana pilots stated that he was preparing to speak up about his airplane's slow speed during descent for landing. The auto-throttles weren't set correctly, and the technology had gotten ahead of the pilots. That pilot decided that it would go against the cultural norm to question the command-pilot's actions. And they crashed.

Your organization's culture must be one that encourages frank, open, and honest discussion about things that concern your safety - or the safety of anyone in your organization. You speaking up may fix my misunderstanding about something that's happening to us in flight.  You may save our lives. You are not a passenger - you are a crew member.

As members of a crew, we coordinate our actions in the aircraft. We don't do anything without announcing it. We touch no switch without confirming which one we want, and announcing our actions. Failing to do this led to a crash of Marlin Air's jet carrying the University of Michigan's transplant team.

Read about this crash by clicking here...

Maintaining situational awareness requires managing the resources available to avoid demanding more from anyone on board or on the ground than they can provide. Separating and fixing responsibility goes a long way to preventing crashes like the loss of an Eastern Airlines jet in the Everglades in 1972 and an EC-145 in the water near Fort Myers FL in 2009. These crashes bear shocking similarities in the loss of situational-awareness while the person flying became distracted by attending to a duty not related to FLYING THE AIRCRAFT. In both crashes, the pilot thought the autopilot was flying the aircraft, and in both cases it wasn't doing what they thought it was.

Imagine if the flying pilot had said, "Hey guys, I am going to focus on flying the aircraft. Can you help my by working on..."

Our brains dislike being "adrift." We like to latch on to a sense of reality (right or wrong) and can easily get led down the wrong path by "expectation bias"  We can have everything all wrong, while thinking we have it all right. Complacency contributes to this, as does failing to use every resource available to confirm what is really happening.

In the helicopter, the one that went into the water, the pilot was trying to call EMS with no luck, and had the autopilot set. When she reduced power to descend to her selected altitude of 500 feet, she inadvertently set the collective too low to maintain the minimum autopilot speed. The helicopter descended to the water while the one person on board who could have been flying wasn't. The crew in back noticed water in the air outside and took it to be rain. It was sea spray. They didn't have situational awareness...

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