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Crashed Boeing Planes Lacked Safety Features That Company Sold Only As Extras (apnews.com)
The recent Boeing 737 MAX crashes involving an Ethiopian Airlines flight and a Lion Air flight may have been a result of two missing safety features that Boeing charged airlines extra for (Warning: source may be paywalled; alternative source). The New York Times reports that many low-cost carriers like Indonesia's Lion Air opted not to buy them so they could save money, even though some of these systems are fundamental to the plane's operations. "Now, in the wake of the two deadly crashes involving the same jet model, Boeing will make one of those safety features standard as part of a fix to get the planes in the air again," the report says. From the report: It is not yet known what caused the crashes of Ethiopian Airlines Flight 302 on March 10 and Lion Air Flight 610 five months earlier, both after erratic takeoffs. But investigators are looking at whether a new software system added to avoid stalls in Boeing's 737 Max series may have been partly to blame. Faulty data from sensors on the Lion Air plane may have caused the system, known as MCAS, to malfunction, authorities investigating that crash suspect.
The jet's software system takes readings from one of two vanelike devices called angle of attack sensors that determine how much the plane's nose is pointing up or down relative to oncoming air. When MCAS detects that the plane is pointing up at a dangerous angle, it can automatically push down the nose of the plane in an effort to prevent the plane from stalling. Boeing's optional safety features, in part, could have helped the pilots detect any erroneous readings. One of the optional upgrades, the angle of attack indicator, displays the readings of the two sensors. The other, called a disagree light, is activated if those sensors are at odds with one another. The angle of attack indicator will remain an option that airlines can buy. Neither feature was mandated by the Federal Aviation Administration. All 737 Max jets have been grounded. "Boeing will soon update the MCAS software, and will also make the disagree light standard on all new 737 Max planes," the report adds, citing a person familiar with the changes. "Boeing started moving on the software fix and the equipment change before the crash in Ethiopia."
Slashdot reader Futurepower(R) adds to the story: The FBI has joined the criminal investigation into the certification of the Boeing 737 MAX, lending its considerable resources to an inquiry already being conducted by U.S. Department of Transportation agents, according to people familiar with the matter. "The federal grand jury investigation, based in Washington, D.C., is looking into the certification process that approved the safety of the new Boeing plane, two of which have crashed since October.
The jet's software system takes readings from one of two vanelike devices called angle of attack sensors that determine how much the plane's nose is pointing up or down relative to oncoming air. When MCAS detects that the plane is pointing up at a dangerous angle, it can automatically push down the nose of the plane in an effort to prevent the plane from stalling. Boeing's optional safety features, in part, could have helped the pilots detect any erroneous readings. One of the optional upgrades, the angle of attack indicator, displays the readings of the two sensors. The other, called a disagree light, is activated if those sensors are at odds with one another. The angle of attack indicator will remain an option that airlines can buy. Neither feature was mandated by the Federal Aviation Administration. All 737 Max jets have been grounded. "Boeing will soon update the MCAS software, and will also make the disagree light standard on all new 737 Max planes," the report adds, citing a person familiar with the changes. "Boeing started moving on the software fix and the equipment change before the crash in Ethiopia."
Slashdot reader Futurepower(R) adds to the story: The FBI has joined the criminal investigation into the certification of the Boeing 737 MAX, lending its considerable resources to an inquiry already being conducted by U.S. Department of Transportation agents, according to people familiar with the matter. "The federal grand jury investigation, based in Washington, D.C., is looking into the certification process that approved the safety of the new Boeing plane, two of which have crashed since October.
The funny thing about this is that nobody responsible for this will actually suffer any real consequences.
It can be disabled by turning autopilot on, NOT off, and anyway the autopilot would disengage immediately because at least this subsystem checks for the consistency of the data coming from the AoA sensors.
Boeing: New Intercontinental Plane only $5 ...
Customer: There are no wings
B: They are extra, it is like with your fees for essentials, like luggage, meals and seating.
C: Oh [pause] And wheels?
B: Extra
C: Seats?
B: Extra
C: How much is it with all these extras?
B: $ 121.6 for the basic configuration
C: Huh?
B: There is also a do not crash feature and avoid mountains features
C: Too expensive. For that price we could by an Airbus
Your translation of [1] is wrong.
That flight was saved by the third pilot (non-flying) who was in a jump seat and could afford the luxury of observation from the side. The two flying pilots were busy with instruments and plane systems. It has nothing to do with experience.
Not really. Bombardier mostly makes regional jets whereas Boeing doesn't build any of them. However, they do make one line that directly competes with Boeing -- the CSeries, which competes directly with the Boeing 737 and Airbus 320. In October 2017 Airbus bought 50.01% of the C series production and the airplane is now being built in Alabama to avoid paying US tariffs. The deal was under-reported by the press for obvious reasons but the outcome is *exactly* why the 21% tariff was proposed in the first place. The airplane is still being built (only now in the US by US labor) and Boeing still has to compete with it.
That's a worthy effort, but any pilot who was fighting against an out of control trim system and thought to himself "hem, let's look in the book to see what to do about my AOA indication" would be an utter retard. The correct way to deal with a malfunctioning trim system is to immediately disable electrical control of the trim system. Figuring out how to deal with faulty AOA indication wouldn't be anywhere near your top ten concerns at that point in time.
Imagine that you're driving down the highway, and suddenly your car starts to accelerate out of control. You, of course, scan the dash, see that the check engine light is on, and think to yourself "let me check the manual and see what to do about a check engine light".
That's the kind of thing you're suggesting here ....
The Seattle Times has a good article on this although it should be taken as preliminary data subject to change.
To summarise
Due to airframe changes from previous models Boeing introduced MCAS which automatically lowers the nose when approaching a stall.
The MCAS was introduced to allow pilots with 737 experience to fly the 737 MAX with a minimal amount of conversion training thus saving airlines a lot of cost and making the MAX even more attractive to them.
As initially designed a failure of MCAS was classed as a "Major" hazard in that it could cause passenger discomfort but not death. This was because MCAS was limited to a very small change to the flight control surfaces. For this category the use of a single sensor is allowed assuming the sensor reliability is sufficient.
During the flight test phase the ability for MCAS was extended to unlimited repeat operations. These repeat operations have a cumulative effect on the flight control surfaces. The MCAS can now lead to a catastrophic failure.
At this point the category of hazard should have been changed. This should have lead to a design change but because the category remained at "Major" and not "Catastrophic" no further changes were made.
There could be any number of reasons why this categorisation change was missed, hopefully any future investigations will get to the root cause.
Who modded that comment to 5? It is all crap
Yours is better? Where does this 50/50 come from?
Airbus is only 18.6% in the US (Boeing 43). And in the rest of the world, that you probably didn't visit much, it's not "Airbus, Airbus, and Airbus". It's roughly 50/50.
Slashdot, fix the reply notifications... You won't get away with it...
The autopilot wouldn't be using the vane angle-of-attack sensor, they would be using air data and the inertial reference system. The only system that I would expect to be using the vane angle-of-attack reading in aircraft that is not fly-by-wire is the stall protection system. The stall protection system normally takes either of the angle-of-attack readings to flag a stall, whichever of the two systems is giving a higher reading. It uses an either-or logic because an aircraft in a banked turn may have differing angle-of-attack readings between the two vanes. An incorrect reading might trigger a premature stick shaker/pusher activation, but as this can be overriden by the pilot it wouldn't be considered safety critical, hence only 2 vane angle-of-attack sensors are needed.
Airbus aircraft, which have fly-by-wire, calculate angle-of-attack independently using the pressure readings from cross-coupled smart pitot tube sensors, which can then be verified against the vane angle-of-attack.
There was no stall. The MCAS system was engaged due to a malfunctioning angle of attack system.