Reply to post: Re: Hey software, get the fuck out of the way!

Boeing 737 pilots battled confused safety system that plunged aircraft to their deaths – black box

Anonymous Coward
Anonymous Coward

Re: Hey software, get the fuck out of the way!

I have heard the various official and unofficial reports about the Air France crash, and I I am not a conspiracy theorist however I suggest that the pitot tube icing was a cause of the incorrect instrumentation reading, and that the icing was picked up by flying too close to a thunderhead...which as you get closer to the equator can top out as high as 60,000 feet.

The airplane 'pancaked in' as the result of hitting the water in a flat spin, the spin resulting from a stall. Not having flown an Airbus 340 or 350, I can't say what the pilot assisted procedure is to recover from a spin, but it would require the fully committed action of someone who had considerable flying ability and experience and knowledge of the state of the aircraft and could apply it within a 3 and 1/2 minute descent window from the point of recognition. There is no glide in a spin and a recovery would likely have taken 10,000 feet of altitude or more for spin recovery and required full power with the aircraft pointed nose down in order for the aircraft to begin flying again which would have consumed additional precious altitude at a faster rate than terminal velocity.

The captain was returning from Brazil with his wife onboard and was not at the controls or on the flight deck when the plane encountered the icing (icing, which is a manageable occurrence). The left seat pilot was an experienced 'type' pilot with almost no experience flying through the horsey latitudes while the right seat had a new pilot to 'type' with many hours flying trans-equatorial. It was a moonless night, with no visual reference (over water), and the non-equatorial pilot flew too close to a thunderhead he was avoiding which led to the icing. Normally you would fly around the thunderheads guided by visual reference or radar, with equatorial thunderheads being of the type that have unique characteristics because of their sheer height. The right seat pilot would have had the knowledge of this uniqueness however he was not the pilot in command.

These planes are built to be able to fly into and through rough weather but for some reason the icing was unexpected.

The captain arrived on the flightdeck at some point in the 'enter into stall', 'stall', or entry into the spin (he detected an unusual change in aircraft or engine pitch perhaps, the remnants of the autopilot system before kicking over to manual).

A spin without visual reference doesn't feel much different than straight and level flight although the electrical based systems such as the INS would have been reflecting the mayhem and toppling. No one was in a position to confidently summarize and positively control the aircraft to exit the spin by deploying spoilers, landing gear, or a hard counter rudder while pushing the nose over applying full power to attempt to get the lift required for the machine to start flying because none of the crew were in the right places, or had the right experience to be sitting where they were sitting.

I hear this flight referenced all the time for the published reasons in this string. IMHO this was an organizational error (on duty captains flying with their spouses) on overnight flights especially when crossing the horsey latitudes, the bad luck of that combination of skills and experience (or lack of experience) on the flight deck at that stage of the flight, a dark and moonless night flying over water not providing any visual reference, and an iced pitot tube which delayed and prevented any present pilot from recognizing the actual state of flight and taking decisive action to stop the spin was the real cause.

While I agree that the software on the Java Air flight was faulty or interpreting faulty data, the 737 Max does differ from the other 737 series probably due to the need to monitor lift (angle of attack) more carefully due to the length of the longitudinal axis, weight capacity and probably ooth. What this means is that an experienced pilot on type would have to have learned about the critical differences between this model and the rest of the 737 models, and learn about the unique recovery procedures (pull the fuse) of the Max.

The pilots should have been forced to learn about the new procedure and been given the information of the critical-ality of the angle of attack on this model. It has not been determined whether or not this took place.

Pulling a fuse to save an aircraft and the souls on-board does seem pretty Mickey Mouse though.

The first thing which I thought of when I heard the report of the crash, although the poor maintenance record of the airline formed the bulk of the initial news article's reason for the crash, was the potential failure of a Neo engine which is an available power plant on this aircraft. This is a new aircraft jet engine which uses a gearing system in order to move a greater number of very thin fan blades at a higher rate of speed using less fuel (per pound of thrust). There have been problems with this engine but when it works it provides an relative economic panacea for the airline.

A safe angle of attack is achieved (and determined) by airflow which is a function of thrust when taking off, climbing and at altitude, and a function of altitude when descending. Maybe the size and weight of the aircraft precipitated the systems modification, maybe the new engine, but in any event this system was new, critical, and persistent.

IMHO no aircraft of this type should crash at 800 hours without any reason short of sabotage. The reason for the unfortunate crash may turn out to be attributed to a combination of mechanical and pilot error with a contributing factor being poor maintenance practices. It is a certainty that Boeing will change the responsible hardware and software system quietly over time.

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