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Comment Re:Pilot Proof Airbus? (Score 1) 132

...as was the case of an airbus that crashed because only one axis of the autopilot switched off unexpectedly.

Sounds like this accident: http://en.wikipedia.org/wiki/Aeroflot_Flight_593 Failure to understand the autopilots control wheel steering mode. Roll mode reverted to manual and pilots failed to recognize it.

Comment Re:Pilot Proof Airbus? (Score 1) 132

In the case of Airbus (excluding A300-A310 IIRC), there is no direct (cables, levers, pulleys, etc) movement of the stab/elevators and ailerons by the pilot. In normal law, the stick position schedules vertical acceleration and lateral roll rate. The rudder pedals directly command rudder surface movement via cables. The stick can only ever move the flight controls through computers. If there are multiple failures of redundant systems the computers revert to alternate then direct law- servos controlled by stick position with no envelope protections.

So, in this case, yes. The computers will not ever let the pilot directly control the plane if I understand your question correctly.

Comment Re:Stall? (Score 2) 132

Stalls in swept wing aircraft at high altitude are difficult to recover from. It takes time and patience to avoid secondary stalls, and usually a significant loss of altitude. AF447 was flyable all the way to impact but improper recovery technique complicated by confusing systems failures were big links in the chain of events.

I have no doubt the FDR's will be found and I think the similarities between these two events is significant.

Comment Re:Pilot Proof Airbus? (Score 1) 132

throttle position is not indicative of actual throttle amount (electronic controls)

The autothrust system in my opinion is extremely well thought out. The thrust levers behave exactly like any other non- autothrottle system when it is disarmed or disengaged. They do not move with thrust changes when engaged, but if there is any doubt one can always operate manually. As for AF447, when they lost air data systems the thrust went to thrust lock until the levers were moved by the pilots: thrust was locked at last setting.

Comment Re:Pilot Proof Airbus? (Score 2) 132

...because a very junior pilot was pulling the stick back *the entire time* and the senior pilot did not realize this

The ECAM (electronic centralized aircraft monitor: http://en.wikipedia.org/wiki/Electronic_centralised_aircraft_monitor) provides an aural alert to the pilots if both sticks are out of neutral. Further, the inputs are additive- one full up and the other full down is summed as zero. This is not to say they heard it- hearing is the first sense to diminish when under stress.

I can't help but think that synchronous flight controls a la Boeing jets would have at least partially mitigated this problem

That question has been debated ad nauseum. Still, Boeing have maintained the synchronous approach and Airbus have remained dual-independent and both have been well thought out in approach and execution. Potato, potahto.

most of the expert opinions I have heard say that the asynchronous nature of Airbus sidesticks was *not* to blame

I concur. I do not claim to be an expert but I am type rated in the A320 and have over 8000 hours flying them.

Comment Re:Developing Story (Score 1) 275

I stand corrected. Perhaps it would have been better to say almost no modern transport category aircraft come equipped to display AOA anymore. While this may be an option that Boeing have begun offering (that article I believe dates from 2012), I have never seen one in use. Do you work for a US certificated carrier- BizJet contract maybe? After looking through our flight manuals for the 787, I see that we do not have AOA display on that type. We are the only US part 121 carrier to operate 787s. I have flown 737,747,757,767,777 and A320 types, but none have AOA and I have not encountered them while jumpseating. I still find AOA irrelevant to modern cockpits- at least transport category cockpits. What's your opinion of AOA presented as part of PFD, useful or not? Target AOA might have some relevance but not when max L/D can be calculated and displayed on speed tape or FMC.

Comment Re:Coffin Corner? (Score 4, Insightful) 275

The moment you stall, you lose altitude, and you're no longer in the coffin corner.

The moment you stall, you are outside the flight envelope which includes that corner. You remain outside until you recover from stall. Losing altitude is not a stall recovery technique. Restoring laminar flow over the wing is. That may involve sacrificing altitude for airspeed, assuming you still have enough elevator authority to reduce AOA. Another method is to use excess thrust, assuming it is available at that altitude (the higher you are the, less available.)

A simple stall recovery, and you're back in normal flight.

Stall recovery in large swept-wing aircraft at cruise altitude is anything but simple. It requires a great deal of patience and energy management to avoid secondary stalls. Once recovered, you remain in alternate or direct law- no more normal law until on the ground and reset.

The A320 in particular is designed so the computer will automatically recover from stalls if the pilots simply release all controls.

Untrue. When you stall an A320, you revert to alternate law (hopefully with speed stability), as normal law will not let you stall. If you stalled, something went wrong. The flight control computers are saying essentially that "I cant fly the plane anymore- you the pilot must do it." It will not recover without pilot intervention.

...one of the pilots on AF447 kept directing the plane to pitch up without telling the other pilot what he was doing, as the other pilot was trying to pitch it down to recover from the stall

This did happen, and they were disoriented but not stupid, just poorly trained. The aircraft also gave them a "dual input" aural warning and averaged their inputs. The first sense to disappear when under stress is hearing. They were under stress and poor training in stall recovery left them unable to prevent secondary stalls. This was one of many other factors to this particular accident as well as all accidents in general.

Comment Re:Developing Story (Score 1) 275

Because Airbus makes shitty Angle Of Attack probes

It was iced pitot tubes that caused problems for AF447. Thales was the manufacturer of the pitot tubes, not Airbus. No modern transport category aircraft come equipped to display AOA anymore. It is no longer relevant in digital flight displays as the quality of flight parameters and method of display is so much better for pilots. However, AOA is still measured and provided to flight control computers.

...controlled by a computer that can't be overridden when it suffers from bad data input.

Completely incrrect. When the computers suffer from lack of information or "bad data" they revert to a fail safe mode; alternate law first then direct law. Basically they get out of the way, not "can't be overridden".

Comment Re:Don't take airplanes piloted by the Malays (Score 2, Informative) 275

The airline should have re-routed it, but that's not entirely the pilot's call.

The route and safety of flight are shared responsibilities between the dispatcher and pilot. The final authority rests with the Captain per regulation. Were the captain to feel deviation or complete re-route was necessary, he had full authority and responsibility to do so. Where ATC is not accommodating, he can exercise emergency authority to preserve safety of flight.

...it was the one the owners of the plane he was flying told him to take.

Point of information: The "owners" explicitly do not have that authority.

Comment Re:These idiots are going to ruin it for everyone (Score 3, Informative) 132

At the speeds commercial aircraft are moving, yes, I could see a pilot mistaking a bird soaring for a RC airplane.

It has less to do with relative speed than relative speed vectors. The most difficult target to see, even when advised of its presence, is coming from a constant bearing decreasing range as there is little change in position with respect to field of vision. I have flown past, on three separate occasions, mylar balloons while at cruise flight levels (FL300-FL390) at 400-450 KTAS. The size and shape are arguably similar to drones, so distinguishing a drone from a bird while at drone operating altitudes should be equally trivial, assuming the event wasn't just a flash in the visual periphery.

Commercial aircraft are moving much faster, and the pilots are busy doing pesky things like preparing to land. Seeing a bird or drone is nothing more than a glance and a "I saw something".

My VMC scan at cruise is much less rigorous than while in a terminal environment. The flying pilot should be scanning outside (VMC), and leaving box work to the non-flying pilot. "See and avoid..."

All that said, I have not ever encountered a "drone" in my 15000 hours of flying, respecting the fact that I don't find myself in the environment (which most likely is not large commercial airports) in which drones operate. OTOH I usually have about 1 birdstrike per year, most of which I never see- only hear the impact.

Comment Crime and punishment... (Score 1) 1198

Not the Dostoyevsky kind but the real thing. As I've aged, I have softened on my stance on capital punishment. My moral side feels that some crimes deserve to be met with death, and my rational side see the flaws in the legal system: far too many errors, especially by "eyewitnesses", mandatory minimums, three strikes, unethical prosecutors. Between those two sides I see how many people we lock up (quite a few are innocent, some sentences don't fit the crimes), and wonder why we still have so much crime in comparison to countries less inclined to incarcerate criminals. I'm shocked at what can cost you your life in many places: drug convictions in Indonesia, blasphemy in Saudi Arabia (can't wait to visit!). Are we somehow a more "just" country because we reserve the death penalty for the most "heinous" of crimes? Is our system of justice meant to punish, deter, or both? The advent of execution by lethal injection allowed us to see it as neither cruel nor unusual. Hangings, beheadings, and firing squads are now too barbaric. But as bunny ("Platoon") says "The only worry you got is dying. And if that happens, you won't know about it anyway." Maybe the method of execution is more about the conscience of those asked to carry it out. As a means to deter crime, no one can say for sure whether a criminal has been stopped short of carrying out a crime because of a potential death sentence. It didn't stop Clayton D. Lockett, but that doesn't mean it's not a deterrent. I understand why his victim's family might support this sentence. When I add it all up, however, capital punishment is loosing its appeal (pun intended).

Comment Re:Pilots crash planes (Score 2) 75

Semantics.

It does not use the term "mechanical". I did- because there was more to this incident than just human error.

It cites in that very first paragraph in 3.2 that the pitot tubes icing over is a failure. If you conclude that because it never says "mechanical" (my term as things that go wrong with the aircraft or its systems are referred to in this way) that there was not a aspect of systems being inop in the outcome, then you are using semantics to make your case.

You made the claim that the "pilots were the cause of the crash". I dispute that simplification of events as inaccurate and misleading. The mishap report concludes that in addition to pilot error, poor training, weather and the "total loss of airspeed information" caused by a (mechanical, sytems, or whatever term you prefer) failure of the Pitot tubes were components of this disaster. Pitot tubes were replaced wherever they were in use, including the aircraft that I am type rated in and have over 8000 hours experience in, as part of Airworthiness Directive that existed prior to this accident. Wonder why...

...perhaps because the Thales versions were prone to "fail" to perform as intended.

Comment Re:Pilots crash planes (Score 1) 75

Take the Turkish Airlines that crashed in Amsterdam.

This incident has some similarities to the Asiana crash in SFO. In both cases, pilots failed to recognize FMA's (flight mode annunciation). In Schipol, the autothrust had changed to retard mode (used during the flare) which allows the airplane to slow below ref speed and land. In SFO, they may have disarmed the autothrust instead of disconnected it, the difference being that they bypassed the low speed wakeup function of the autothrust which prevents low energy conditions.

In both cases, pilots lacked understanding of the automation. However, in the first case the automation malfunctioned.

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