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Comment Aural feedback (Score 1) 823

I don't see at as such a "dirty little secret". I see it more as a drivers tool- much like a dead pedal or an electronically adjustable differential. Perhaps it would be better to view it at as a means to inform the driver through aural feedback of engine speed, load and shift points. The fact that they tweak it to make it sound "cool" is just a bonus.

Cars have become both quieter and more powerful, as well as idiot proof- I kind of prefer the days where one had to work at it to drive well.

Comment Re:Republican (for the record) (Score 1) 136

After reading your post, I was unsure whether you hate R's or D's. So I look at your sig and do some brief investigating and find that you hate both- fair enough. But keep in mind the "political realities". That change always faces opposition, and rate of change is determined by the degree of opposition. Why anyone votes Republican (other that the ruling plutocracy) is still a mystery to me, but one cannot expect the "political realities" to be overcome in an instant. And the R's have resumed control of congress- deity help us. Perhaps you should run for office. I know of a county in Maryland that needs politicians with greater awareness of The Constitution

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.

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