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Human Judgment better than Technology?

While having morning coffee with my work colleagues, we got into a discussion which surrounded how complex technology is getting now and is human judgment getting affected by it. One of my work partners then touched base upon the Air France Flight 296 that crashed in a dense forest as part of an airshow. This brought up more view points on complex technology from my team and that’s how this discussion started.

Air France Flight 296, a brand new fly-by-wire Airbus A320-111 was one of the three newly built aircraft delivered to Air France in 1988. On 26th June 1988, the aircraft crashed into a forest near Mulhouse–Habsheim Airport, Mulhouse, France while in an attempt to make a low-level fly-pass. Three people died as a result of this accident. This accident investigation was an interesting one, which still years after the accident leaves with an unanswered question, “Is human judgment better than technology?”

af296, human judgment

The aircraft involved was delivered to Air France just two days before the crash. Air France was keen to show the new aircraft to its customers and hence the low-level fly-pass was decided to be performed as a part of the journey. The crew, Captain Asseline and First Officer Mazieres were not informed about the flight plan until the morning of the journey.

As the crew approached the Mulhouse-Habsheim airport to execute the fly-pass, they noticed the spectators gathered near Runway 34R, a 1000 feet shorter strip than Runway 02 which was the original Runway in the flight plan. This caused a bit of distraction as the crew now had to change their heading, direction, rate of descend and speed accordingly to line up with Runway 34R. This panic moment in the cockpit resulted the aircraft levelling up at 34 feet rather than 100 feet where it was supposed to execute the fly-pass. However, this change of altitude went unnoticed.

The crew then decided to execute the low-level fly-pass and follow the flight plan. Captain Asseline decided to lower the third stage flaps. The aircraft speed was slowed and the landing gear was deployed. To show a better view of the aircraft and its new fly-by-wire technology, “Alpha Max” was also achieved. Alpha Max is the maximum angle of attack an aircraft can attain at a certain speed to continue maintaining lift on the wings and not stall. Now, the first thing to note here is the human judgment; the aircraft was slowed, flaps lowered, landing gear deployed, and nose up position – a typical landing procedure?

Captain Asseline then also disabled a function called the “Alpha Floor”. Alpha Floor is a protocol in fly-by-wire system which automatically increases engine power thrust when maximum angle of attack (15 degrees) is reached. What would have made Captain Asseline decided to disable Alpha Floor and hand over engine thrust to First Officer Mazieres? Even though if that was the case, pilots are trained to be able to fly the aircraft manually no matter how much sophisticated the cockpit is. In any condition, a pilot should be able to hand fly the aircraft.

Captain Asseline assured First Officer Mazieres that he has quite an experience under his belt for such fly-pass maneuvers. But did Captain Asseline specifically mention that he has that experience in this aircraft type? The primary intention of this fly-pass was to show the audience the capability of this aircraft and the technology incorporated. It was meant to be done in such a way that the flight regime would be extended to its flying limits and show how the fly-by-wire system would still be capable of flying the aircraft.

Did the crew had enough background and knowledge/training on this aircraft? What all I want to say is that although the flight crew was an experienced one, were they over-confident about their flying skills and their judgment calls? The reason that I am writing this discussion is because of what happened next.

As the crew were performing the fly-pass, the captain finally realized that his bird was flying too low and has a chance of possibly hitting the dense forest ahead of Runway 34R. To remedy the situation, First Officer issued a Go-Around command. Go-Around is a procedure when the crew determines that landing the aircraft in a given circumstance is not the best safe option, and gives full power to the engine to take-off again and abort the landing. Hence the crew pushed the throttle to have full engine power thrust and that’s when technology took over the human judgment. Airbus’s newly incorporated fly-by-wire system kicked in at that right moment. The system, based on the aircraft’s current position (slow speed, flaps lowered, landing gear deployed, and nose up position) and also on the fact that the fly-pass was being executed at a level altitude (34 feet), assumed that the aircraft is trying to land but is not able to. It is also to be noted that the pilot’s command of Go-Around and his consequent actions are disputed, since many irregularities were later found in the investigation (Actual Report).

Hence the fly-by-wire system overrode the crew’s request to go around and as a result, the aircraft crashed in dense forest ahead of Runway 34R. This leaves us with a question that has no correct answer, according to me. Is technology getting too advanced that it is hampering manual flying ability of pilots? Is the human decision less reliable now? Should technology have a higher precedence over human calls? Before answering this question, one should also take into account the fact that air travel has now become way safer by learning from the outcomes of such incidents. Aviation Analysts say that it is safer to fly in an aircraft, than to cross a street in downtown Toronto.

As a growing technology enthusiast, I would love to hear from you, any questions, comments or concerns that you may have regarding this discussion. Please feel free to leave your view point in the comments section below.

 

 

Resources Taken from – “http://aviationknowledge.wikidot.com/asi:air-france-296” and “http://www.airdisaster.com/photos/af296/10.jpg

Published inEngineering

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