I contend that the primary cause is not the sensor but the overconfident reliance on autopilots. When an autopilot intervenes, its whole purpose is to resume stable flight. Should anything unacceptable happen instead, the autopilot ought to switch itself off. Too many (blind) cooks spoil the broth.
Actually, I am shocked at how sloppy their approach to reliability engineering must be not to have even thought of such a basic thing. Reminds of that NY finance company that lost half a billion $ in half an hour because they could not turn off their buggy automatic trading system.
Numbers show that as Automation has gone up and crashes have gone down. It doesnt establish causation but correlation is a supporting data point.
Additionally, in many of these systems, autopilot does give back control and the pilot in a panic proceeds to royally screw up. The France flight 447 is a specific example of this.
The best way to handle this is to not only train the pilots differently but to change the autopilot. Multiple redundant sensors using different ways to measure airspeed so the detection of a faulty sensor is possible through automation.
Pilots and machines are nowhere near perfect. The goal is not to put both systems at odds, but to move both towards perfection.
The instrument malfunctioned, but one pilot was pulling a lever up, while another pilot was pulling another lever down. This generated a stall. It could have been avoided if the cabin was more well lit, so that the pilot making the error could have been visually seen to be making the mistake.
Boeing uses force feedback so the two pilots are aware that something is counter-acting their input.
I really don’t think the Airbus strategy is defensible - certainly not when the two inputs are far apart!
Boeing is responsible in the article too: adding such new feature without properly communicating with the pilots??
Maybe the pilots did not receive proper sim time on a 737MAX, which I believe has different enough instrumentation and automation systems to require a separate sim from the standard 737. But they almost certainly knew which systems were on the plane, and how to operate them under normal conditions.
Isn't part of Boeing's marketing strategy that the 737MAX actually DOESN'T require additional training? The entire point of MCAS is to make the larger 737MAX react to control inputs just like a smaller 737, so flight crew can just fly them all "like a 737".
Airbus statement on sidesticks. [1]
Boeing position on sidesticks.[2]
This is a long-standing controversy. The F-16 fighter was the first aircraft produced with a sidestick. But that was so the pilot could control it during high-G maneuvers. Airbus's use of it has been controversial for years. For a good overview of the Airbus control system, read "Fly by Wire", by William Langewiesche.
But that wasn't the problem with Lion Air.
Airspeed. Attitude. Vertical speed. Altitude. If the pilot is operating on wrong information for any of those, they may lose control of the aircraft. All large aircraft have more than one of each of those. But when they disagree, or fail in a common mode, big trouble.
Whether some other data source like GPS or inertial should be used to back up those is an open question. GPS can and is jammed. Inertial systems drift. Both are complicated. The classic instruments are so simple. But they rely on tubes to holes in the aircraft skin, which might become plugged for a number of reasons - ice, maintenance covers, insects, or dirt.
[1] https://safetyfirst.airbus.com/app/themes/mh_newsdesk/docume...
If you read the whole transcript and report it really does show just how wrong the pilot pulling back got it. And it speaks to the training and understanding that pilot had of how to fly the electronics vs how to fundamentally fly an aircraft.
He quite literally kicked down the door to the cockpit and asked "What the hell are you doing?"
Moments later, the co-pilot at fault said "but I've had that stick down the whole time!"
Captain: What the hell are you doing?
Benin: We've lost control of the plane!
Robert: We've totally lost control of the plane. We don't understand at all... We've tried everything
Now, instead of a team working jointly on a problem, we have two juniors feeling that they have to justify and defend themselves to their captain. It’s a really poor psychological position to be in with a time-critical problem to be solved.
It’s a human response, obviously, but I’m betting it’s the opposite of what his training would have recommended.
IMO, in that moment, the Captain either needed to get his crew problem-solving, or take control himself. unfortunately he did neither.
But I think at this point the plane was plummeting belly down (not nose down) to the ocean and they only had like 90 seconds to live.
By that point I think they all knew they were dead, even though their words don't indicate it. They were in pitch black conditions :(
There was time, if only someone had said the word ‘stall’ out loud.
I don't know easily panicked mentality can be tested for. Training is one thing, but training is typically designed to instill automatic response to predetermined stimuli. Sometimes what you want is a reset back to first principles and activation of conscious reasoning. Which is exactly what you don't get in shock or panic, and is the reason for training automatic response.
Being well lit is one part. But also, if the pilots had been in a Boeing that may have helped as well.
Airbus joystick vs Boeing yoke. The latter would have provided feedback to the pilot not panicking and pulling up incessantly
The problem is going to get worse. Right now we have thousands of vehicles with trained highly-regulated operators (airplanes) relying on automation, who can be complacent until the automation fails and then must be alert and able to handle a complex situation in a matter of minutes. Soon, we will have millions of vehicles with barely-trained almost unregulated operators (cars), relying on automation, who can be complacent until the automation fails and then must be alert and able to handle a complex situation in a matter of seconds.
You are describing a navigation system, not a flight computer or an emergency recovery system.
Flight 301 - 1996 Flight 447 - 2009 Flight 703 - 2018 Lion Air - 2019
Flights per year: 40 million just this year
https://www.statista.com/statistics/564769/airline-industry-...
No amount of engineering will save you from this, if you add more they'll maintain it less so that'll fail instead.
The Emergency Airworthiness Directive issued after Lion Air 610 crash was, in summary, "Pilots, remember that there is a runaway stabilizer QRH response and pilots should follow that when indicated."
If you're arguing that the pilots didn't know about the possibility of runaway trim, I don't find that very likely. If you're arguing that they didn't specifically know that MCAS could cause runaway trim, I probably agree but think it's irrelevant as the response to runaway trim is not to diagnose or draw the system diagram of the fault, but rather to simply stop the fault, which the stock 737 checklist would have accomplished, if followed.
You would almost certainly see better returns if those same resources were put towards improving cars, or roads, or curing disease, or infant mortality, or healthcare, or education.
For example, twin engines are statistically safer than more engines, and Boeing had to lobby the FAA to allow them over water.
For another, Boeing wings do not have hydraulics that extend past the engines. Torque tubes are used to transmit power further. This is so that a major engine failure won't damage the hydraulic system. This was not a requirement until a crash from another manufacturer's airplane was due to such damage, and Boeing airplanes were not susceptible to that failure mode.
Your theories about how the industry works are speculation.
The twin engine statistics story that you cite is not the story that I remember for the 777.The FAA had rules which were based on the behaviour of old engines and dictated that an twin engine aircraft should be a smaller distance from an emergency strip than was possible for the best routes across the major oceans (I believe it ruled out the Pacific routes completely). Boeing demonstrated (successfully and correctly) that modern engines failed so rarely that the four vs two distinction was obsolete.
What has happened in recent years is that another failure mode has emerged, it's a complex one due to pilot training, HCI and the vulnerability of automated systems to failure in modes where common sense knowledge could protect them. I expect and believe that the systems and institutions of the aerospace industry will be fully strong enough to manage this, but I don't think that this is the case for many other industries that are beginning to experience the same sort of problems - notably self driving cars and computer medicine.. Many people think differently - the test of theories is time, so we shall see.
Not everyone (including myself) has the same morals as you.
It's surprising to me that airline designers continue to add sensors and computers and automation, when in so many of these cases it's the automation which itself is the problem.
Would the NTSB ever issue a recommendation like "Your aircraft is too complex" or "You rely on too many computers"? It seems to me like that could be a valid cause, but it's simply not in their vocabulary.
New features can indeed raise unanticipated problems. But that automation isn't added for the lulz, it is added to address other safety problems. The safety record has gotten dramatically better over the decades, and that speaks for itself.
> Would the NTSB ever issue a recommendation like "Your aircraft is too complex" or "You rely on too many computers"? It seems to me like that could be a valid cause, but it's simply not in their vocabulary.
Neither of those vague hand-wavy recommendations are actionable, so the NTSB would never issue them.
But most often what's needed is smarter machines, not less of them.
Inadequate engine performance during take off is a periodic cause of problems. Research was done into whether airports could add markers so that pilots could tell if their acceleration was less than expected. That went nowhere because humans don't have an accurate sense of acceleration or time passing. Today new Airbus jets integrate their position over time and will warn audibly "Check acceleration" if underperforming, long before V1 (maximum abort speed). Meanwhile a common underlying cause of inadequate performance is entering incorrect air temperature, modern Boeings will delete input temperatures that don't resemble the measured temperature at an air intake when the engines switch on. Pilots must enter a plausible temperature and try again, or perform a fully manual take off. So investigators now might recommend one or both of these countermeasures be adopted, or that the research be done again knowing these options exist.
https://www.ntsb.gov/news/speeches/CHart/Documents/hart-2018...
Small nit: V1 is the takeoff decision speed, not the maximum abort speed. If the decision is made to abort right at V1, the airplane will continue to accelerate for a second or so while the crew implements the first action to effect the abort/RTO.
An inertial measurement system cannot measure velocity. It's insensitive to which inertial frame it is in. (to move from a non moving frame to a moving frame, you must accelerate, which it could detect. but then you have to integrate these accelerations over time)
Inertial systems integrate all measured accelerations over time to compute present velocity and position. They are periodically corrected with external references. The accuracy is limited to the accuracy of the accelerometers, the sampling frequency and the accuracy of the digital math, among other things.
This IMU idea could be used, but I am not aware of any current commercial IMUs in airliners - but I am not an airline pilot so that does not count for much.
If I were given conflicting information I would see how the plane is acting. I have flown planes with various primary instrument failures over my decades, some in actual instrument conditions, and always had sufficient secondary sources of data to determine the situation. As an example in a piston plane: Tachometer fails? Cross check fuel flow, manifold pressure and airspeed - subject to mixture control which can be reasonably set using "lean to roughness and enrich" method. Been there, done that. I have had an altimeter fail insidiously slowly, when water got into the static lines (despite redundant ports and properly routing them upward), while in actual near minimums in a non precision approach. (I used GPS altitude cross reference and odd seeming behavior of altimeter needle to diagnose and switch to alternate static.)
Importantly, if the plane is flying straight and level and sufficiently fast, over time this becomes a "feel" and you can tell if something is extraordinary. Maybe not on airliners, but definitely the piston planes I fly a lot and probably the small jets I fly on occasion.
This is why some of these things are mystifying to me. If your engines are set to a certain power and seem to be operating properly, and your attitude is just so, in the absence of unusual meteorological conditions your plane should be performing in a manner consistent to your last experience. If your stall warning is going off, well, maybe the instrument broke. Air France is really scary mystifying.
Look, I am a software engineer so I get it, people can get locked into a misconception about a fault and not step away long/far enough to consider other alternatives. It happens a lot in debugging. But for whatever reason my brain works much faster and more dynamically when shit happens in the left seat of an airplane having problems.
Maybe you didn't intend it but this sounds a lot like "couldn't happen to me!"
I meant to mean "It has most definitely happened to me" although not yet in the context of piloting - but in other contexts.
For the Lion flight, winds were light and the aircraft was at low altitude, so ground-speed would have been very close to airspeed.
In any case (as pointed out by earlier comments) a proficient pilot should have no trouble flying in daylight and good conditions using only the "Mark I eyeball". It appears the aircraft crashed because the crew didn't fly it - a surprisingly common occurrence for automation-dependent crews!
I still think I'll be surprised if accelerometers provide useful velocity information over timescales useful to a pilot. But maybe that's because I only have experience with cheap MEMS accelerometers from around 15 years ago.
More useful at the time would be to set a "sensible" power level and maintain approximate altitude ... and looking out the window is usually helpful!
- Birgenair Flight 301 - B757. Pitot tube clogged possibly by insect nest, false overspeed indication, autopilot commanded pitch-up, alarms, stall warning, crew confused about speed, loss of control. 189 dead.
- Air France Flight 447 - Airbus A330. Well known. Pitot tube clogged by ice, confusion about airspeed, loss of control. 228 dead.
- Saratov Flight 703 - An-198. Pitot tube frozen. Three airspeed indicators all disagreed. Loss of control. 71 dead.
- Lion Air - Angle of attack vane failure, from parent article.
That information could be checked against GPS, and at least one aircraft does this. But that has its own problems.[1] Checking against an inertial system is another possibility. Those are complicated, though. The classic airspeed, altimeter, and angle of attack vane are so simple.
[1] https://www.gpsworld.com/gps-disruption-a-full-fledged-aviat...