Computer Error Caused Qantas Jet Mishap 389
highways sends word that preliminary investigations into a Qantas Airbus A330 mishap where 51 passengers were injured has concluded that it was due to the Air Data Inertial Reference System feeding incorrect information into the flight control system — not interference from passenger electronics, as Qantas had initially claimed. Quoting from the ABC report: "Authorities have blamed a faulty onboard computer system for last week's mid-flight incident on a Qantas flight to Perth. The Australian Transport Safety Bureau said incorrect information from the faulty computer triggered a series of alarms and then prompted the Airbus A330's flight control computers to put the jet into a 197-meter nosedive ... The plane was cruising at 37,000 feet when a fault in the air data inertial reference system caused the autopilot to disconnect. But even with the autopilot off, the plane's flight control computers still command key controls in order to protect the jet from dangerous conditions, such as stalling, the ATSB said."
Questions: (Score:5, Interesting)
"About two minutes after the initial fault, (the air data inertial reference unit) generated very high, random and incorrect values for the aircraft's angle of attack," the ATSB said in a statement.
Correct me if I'm wrong but don't most modern aircraft have an inertial navigation system and a seperate angle of attack transmitter protruding from the plane? Why no redundancy?
The incident was the fourth involving Qantas planes in two-and-a-half months[read TFA for the other 3 incidents]...
The plane's French-based manufacturer has issued an advisory on the problem and will also issue special operational engineering bulletins to airlines that fly A330s and A340s fitted with the same air data computer, the ATSB said.
Does Qantas' aircraft maintenance suck or does Airbus' quality control suck? Do both suck?
;)
Finally, shame on the PR guys for blaming passenger electronics. Maybe it's a feature, not a bug...in case any government decides that they want to make another 9/11
Thanks, I'll pass on that flight... (Score:4, Interesting)
...until you get all the bugs worked out of those systems. And unfortunately, lessons of these kinds are often paid in tragedy. These passengers should consider themselves lucky that the pilots reacted so quickly.
Not trying to be too flippant, as I can scarcely imagine the complexity of trying to create what essentially needs to be an infallible system in such a complex problem space. As a programmer, thinking about putting my life in the hands of a computer program scares the living hell out of me. The whole issue is that computers, by and large, lack "common sense", and are prone to accept garbage input without question.
Apparently, this was caused by "a malfunctioning computer". Isn't there sort of redundancy check on anything that could cause the computer to send the plane plummeting toward the earth? One faulty computer can cause this? I'm sure the article is over-simplifying the problem, but still...
Re:Questions: (Score:5, Interesting)
Why no redundancy?
Exactly my thought.
IANAE, but the Wikipedia says An ADIRU acts as a "single, fault tolerant" source for both pilots of an aircraft., and there are 3 ADIRUs.
From TFA,
faulty computer triggered a series of alarms and then prompted the Airbus A330's flight control computers to put the jet into a 197-metre nosedive.
I wonder whether the control computers are programmed to take decision to nosedive just like that OR consult other ADIRUs OR alarm the crew before taking that kind of decision.
Having worked for nuclear installations where I designed automations for, which always demanded to have 2 out of 3 voting redundancy and a careful fault tree analysis making sure no single point of failure would lead to any kind of disaster, I feel the control computer might have been taking decision without consulting other ADIRUs OR all 3 ADIRUs went bad at the same time. And both cases look very scary.
Just my thoughts.
Re:Thanks, I'll pass on that flight... (Score:4, Interesting)
Strictly speaking, the Ariane 5 first flight mishap was a specification bug, not a coding bug, so it depends on your definition as to whether it was really a "software" bug. (Even more strictly speaking, it was a procedures bug: they left running an inertial measurement unit that wasn't needed after launch (it provided ground reference for the nav system while on the pad). They'd done this on Ariane 4 but the 4's flight profile didn't take the unit out of limits the way 5's did.)
Re:Questions: (Score:5, Interesting)
If Qantas cuts the costs of maintenance to such a degree that fatalities are not only likely, but inevitable, can anyone actually be charged with murder?
Re:Been there, done that (Score:5, Interesting)
Cheapest way to experience zero G? Go along to your nearest glider/sailplane club and have a trial lesson. If you ask nicely, some of instructors will give you an aerobatic flight (loops, wing-overs, stalls, but not spins).
If the cable breaks during a winch launch, at a couple of hundred feet, you go zero g in order to recover. The motto is that if the mud (on the floor) floats around your face then you got it about right, whereas if it plasters itself on the canopy then you were too enthusiastic.
Before you go solo (which you can do at age 16/15/14 depending on where you live) you have to be able to repeatedly demonstrate that you can recover from cable breaks and also from a spin started at 1000ft in which you are descending at 100ft/s.
Not an experience you will forget.
Re:Don't forget the spin (Score:5, Interesting)
So what if they do make such claims?
If all it takes is a kid with a gameboy to bring down the Airbus then their entire fleet should be grounded.
The aircraft systems design would be completely unsafe as there are far more powerful transmitters in any urban area.
No, in truth, Airbus planes would be raining from the skys if it were indeed susceptible to such interference. It would have never been certified.
But more important, why did the controls not respond to the pilots? Why would the computers be programmed to prevent a Stall in an *diving* aircraft?
Re:Don't forget the spin (Score:5, Interesting)
If the pilots lost consciousness they would lose control of the aircraft and may slump on to the controls and put the plane into an unsafe course.
The computers put the plane INTO a dive to prevent a stall they *thought* was taking place.
In this case the pilots attempted to abort the 'safety' maneuver but the computer decided that the pilots through incompetence or perhaps incapacitation did not actually intend to kill all aboard and took the action it thought was necessary.
Re:Questions: (Score:2, Interesting)
Re:Questions: (Score:2, Interesting)
I happen to know someone who worked at Airbus in the 90s. Lets just say the early software had a few bugs that needed to be ironed out. But of course its far easier to blame the pilot in a rigged trial than ruin a large proportion of the european aircraft manufacturing industry.
Re:Questions: (Score:3, Interesting)
Put simply - there have been 3,572 A320s built to date and continues to be one of the fastest selling passenger jets of all time, if there was a problem with their control system then where is the evidence? Where is the lack of confidence? Where is the customer doubt?
Also, the fact that Airbus has taken on other significant Airworthiness Directives without an issue casts extreme doubt on your conspiracy theory.
Re:Been there, done that (Score:3, Interesting)
put the jet into a 197-meter nosedive.
the assholes who refuse to keep their seatbelt fastened while seated quickly
Actually I think a lot of the people who got hurt in this case were either in or waiting for the toilet. One could ask why the toilet doesn't have seat belts and why you have to stand to queue for the loo.
Re:Questions: (Score:2, Interesting)
Re:Don't forget the spin (Score:5, Interesting)
Most active cell phones won't cause problems. Hell, I've accidentally left my cell phone on while flying IFR and I didn't notice a thing. The track on flightaware didn't show any problems either.
The problem is that we don't know for certain that the cell phone is working properly. This is why we have regulations such as 14CFR91.21 [gpo.gov] and policies that below 10,000 AGL, you may not operate any instruments.
A quick look at NASA's ASRS database shows 9 entries concerning potential interference from portable electronic devices. So this isn't just an academic concern. Several of these entries indicated that the reporters had seen these sorts of issues before, but that it hadn't been reported.
When the flight crew tells you to shut off your toys before landing, gentlemen (and ladies, if there are any here) SHUT IT OFF! The risk of a screw-up is not yours to take. You can scream and holler at the flight crew about the injustice of denying you ten more minutes on your crack-berry once you're safely in the terminal building. Until then, their word has the full force of Admiralty Law. Shut it off or they'll do it for you.
Video of Airbus A320 Testing Flight Envelope (Score:2, Interesting)
Re:Video of Airbus A320 Testing Flight Envelope (Score:2, Interesting)
Actually, 3 people died, one who couldn't undo her seat belt, a disabled child, but I have forgotten the third. All died of smoke inhalation.
It was the "launch" flight of the first commercial "fly-by-wire" plane, taking paying passengers between cities, albeit with an airshow appearance in between.
The plane was perfectly airworthy when it hit the ground. The myth of a computer glitch in this instance centres on speculation and fear of the pilot no longer having direct control over the hydraulics. The "alpha floor" function of the fly-by-wire system prevents the aircraft from stalling. It didn't actually activate in this instance.
Overall, the pilot was too low, too slow and by the time he realised, too late. Air France management approved the additional joyride as a PR junket, and changed the flight plans at the last minute from a different airfield nearby - which was a mistake in itself.
It's one of those cases where everything is not as it seems. http://en.wikipedia.org/wiki/Air_France_Flight_296 [wikipedia.org]
Re:Questions: (Score:2, Interesting)
Re:Thanks, I'll pass on that flight... (Score:5, Interesting)
In an airplane, the time between when I realize that things are not as they should be and the time when I won't be thinking anymore could be measured in minutes. That is a pretty chilling thought for me...
Don't worry! Most of the time, you never know what hit you in an airplane catastrophe. If the aircraft breaks up at 35,000 feet (as a result of a mid-air collision, fuel tank explosion, terrorist attack, etc.), you're none the wiser. You'll probably be killed by flying debris within a second, and if you survive the break-up, you'll have the oxygen boil out of your blood a few seconds after that.
Much more frequently, you'll hit a mountain while flying in zero visibility. Zero seconds to worry.
A large portion of accidents occur when the plane lands. Tail or wing strike, skidding off the runway, etc. These calamities are likely to occur even more rapidly than a car crash. You probably won't be able to complete the sentence "Oh shi----!"
Or maybe your plane is overweight and can't get enough power to take-off properly. In this case, you've got 20 seconds max to contemplate your fate. And it will probably take you 10 seconds realize that it is really happening. "Why is it taking so long to take off? Is the plane really flipping upside down? Is this REALLY happening?? Oh, oh, yes, it is..."
Being in a plane that plummets to the ground for a minute or two isn't that likely. When seated on your flight, you should really be aware that your life could be snuffed out without warning at any minute.
Re:Don't forget the spin (Score:5, Interesting)
Auto-pilot can make mistakes. But humans make mistakes much more frequently. We are all safer if we turn the piloting of heavy machines over to computers. That California train wreck never would have happened if we had taken the emotional, error-prone sack of meat out of the control system.
Re:Don't forget the spin (Score:4, Interesting)