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Boeing: Profits 1st, Safety 2nd? (Part 3)
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ML1 Send message Joined: 25 Nov 01 Posts: 21325 Credit: 7,508,002 RAC: 20 |
And is this where Boeing is trying to make their 777x into another 737 MAX?... Boeing 777X In Trouble Insider Reveals: The FAA Says Aircraft Certification Is Still Years Away To me, that sounds like a deadly Ouch! Incredible. Deadly greedy. Ignorant. Fly safe folks! Martin See new freedom: Mageia Linux Take a look for yourself: Linux Format The Future is what We all make IT (GPLv3) |
Gary Charpentier Send message Joined: 25 Dec 00 Posts: 31043 Credit: 53,134,872 RAC: 32 |
There is supposed to be enforced the design doctrine that aircraft systems must fail safely or must fail to a benign state... Something that instead has to be actively turned off to avoid deadly catastrophe for normal flight is an inherently deadly design... The auto-pilot is one system designed exactly the opposite of your safe idea. When it fails it will do so with whatever pitch, roll and yaw inputs it last had. You might be lucky and that be straight and level, or you might not be so lucky and it is pitch down adverse yaw, wing low. That is of course if it fails and happens to alert the pilot that it no longer is in control. All too often they only blink an idiot light which can take some too long time for a pilot to realize, especially with the pilot is head down briefing an approach plate. Is the idiot light even wired so if a circuit breaker trips the light comes on or is the power for the light through the now open circuit breaker? Indeed, there is a world of difference in the expense of merely training a pilot to fly vs the extra time needed training a pilot to fly for other than normal conditions... Hence why the training must include the very real possibility of run away trim inputs and making how to shut off electric trim inputs a memory checklist item. Frankly for any airplane with full motion simulator there should be at least one flight where they have to fly a severely mistrimmed aircraft to experience the control column forces needed to maintain control. Aviate, Navigate, Communicate, Troubleshoot. That order. (There are a couple of exceptions to troubleshoot last, such as fire in the cockpit or explosive decompression, but they are of the type where you need to deal with the situation first because if you don't the rest won't matter.) |
rob smith Send message Joined: 7 Mar 03 Posts: 22569 Credit: 416,307,556 RAC: 380 |
When it fails it will do so with whatever pitch, roll and yaw inputs it last had This is not totally true. One failure mode of an autopilot is that it "freezes" as described. Others include pushing one control set (ailerons, elevator, rudder, throttles each being a control set) just out of the desired line. This is scary because the flight crew may not notice for some time. Or it might push one set to a limit. Some are more immediately noticeable than others, and how noticeable may depend on external factors. Or several may be pushed to limits. Or one or may may be "oscillated" in an un-damped manner. Or flaps/landing gear may be incorrectly deployed/retracted. Or, or, or........ As far as I'm aware all of these have happened over the years, and across many types of aircraft. Which and how many can/have happen is influenced by the system design of both the aircraft and the autopilot systems in place. Bob Smith Member of Seti PIPPS (Pluto is a Planet Protest Society) Somewhere in the (un)known Universe? |
ML1 Send message Joined: 25 Nov 01 Posts: 21325 Credit: 7,508,002 RAC: 20 |
Which is suspiciously what looks to have happened to the latest all-fatal Boeing 737 (Classic or NG?) death-dive crash. The throttle for one engine 'crept' backwards to give asymmetric thrust between the two engines. The autopilot flying the control surfaces held on against an ever increasing yaw until finally giving up and dumping an extreme attitude non-flying aircraft onto the startled pilots. Really...? There are no prior warnings that the autopilot is having to work far too hard and is outside of safe (recoverable) margins?... Fly safe folks! Martin See new freedom: Mageia Linux Take a look for yourself: Linux Format The Future is what We all make IT (GPLv3) |
Gary Charpentier Send message Joined: 25 Dec 00 Posts: 31043 Credit: 53,134,872 RAC: 32 |
Really...? There are no prior warnings that the autopilot is having to work far too hard and is outside of safe (recoverable) margins?... Warning was there all the time. All they had to do was look at the throttle lever. The problem is when the automation works so damn good all the time humans stop monitoring it. See Dan Gryder. |
W-K 666 Send message Joined: 18 May 99 Posts: 19422 Credit: 40,757,560 RAC: 67 |
Boeing slows 787 production to address forward pressure bulkhead manufacturing issue Boeing is slowing 787 production in order to address a new manufacturing issue that the company says involves an issue with the jet’s forward pressure bulkhead. |
W-K 666 Send message Joined: 18 May 99 Posts: 19422 Credit: 40,757,560 RAC: 67 |
Another problem for the 737. FAA orders checks on 9,300 Boeing 737 planes for possible switch failures WASHINGTON, July 15 (Reuters) - The Federal Aviation Administration (FAA) on Thursday issued a directive to operators of all Boeing Co (BA.N) 737 series airplanes to conduct inspections to address possible failures of cabin altitude pressure switches. Boeing initially reviewed the issue, including the expected failure rate of the switches, and found it did not pose a safety issue. Subsequent investigation and analysis led the FAA and Boeing to determine in May that "the failure rate of both switches is much higher than initially estimated, and therefore does pose a safety issue." |
ML1 Send message Joined: 25 Nov 01 Posts: 21325 Credit: 7,508,002 RAC: 20 |
Thanks for that one! ...It was prompted after an operator reported in September that both pressure switches failed the on-wing functional test on three different 737 models. So... Where have we seen this potentially deadly scenario before? As I personally see the scenario: Boeing fluffs the design-and-test-and-QA-checks; Operator reports faults/concerns; Boeing denies any problem; FAA chases up long after the event to too late declare a real problem; Work-around minimum cost 'fix' agreed; Pilots and passengers fly on their prayers...
See new freedom: Mageia Linux Take a look for yourself: Linux Format The Future is what We all make IT (GPLv3) |
Gary Charpentier Send message Joined: 25 Dec 00 Posts: 31043 Credit: 53,134,872 RAC: 32 |
Another problem for the 737. My question, who builds the switches? Are they in other airplanes? Spacecraft? |
W-K 666 Send message Joined: 18 May 99 Posts: 19422 Credit: 40,757,560 RAC: 67 |
My question, who builds the switches? Are they in other airplanes? Spacecraft? No idea, but have they been 'grandfathered in' and therefore could be late 50's or early 60's design and that there are better more reliable alternatives available. |
Gary Charpentier Send message Joined: 25 Dec 00 Posts: 31043 Credit: 53,134,872 RAC: 32 |
My question, who builds the switches? Are they in other airplanes? Spacecraft? In the world of certified aircraft, once a design is blessed, er certified, no one dares make a big improvement because obtaining a new certification will bankrupt the investors. There have been a number of biz jets that have obviously depressurized and flown until they run out of fuel over the years. A shared bad part or part design? |
W-K 666 Send message Joined: 18 May 99 Posts: 19422 Credit: 40,757,560 RAC: 67 |
My question, who builds the switches? Are they in other airplanes? Spacecraft? But no doubt they would have no problem with introducing newer designs if it came with a significant weight and size reduction in the item. |
Gary Charpentier Send message Joined: 25 Dec 00 Posts: 31043 Credit: 53,134,872 RAC: 32 |
My question, who builds the switches? Are they in other airplanes? Spacecraft? Significant? Guessing, but even leaving it off entirely isn't going to be significant. A 50's design would be what, the sealed cans of a barometer and a micro-switch? https://www.starpath.com/fischer/pics/new_pics/Fischer_Aneroid_Barometer_Movement_Dial_Large.jpg |
ML1 Send message Joined: 25 Nov 01 Posts: 21325 Credit: 7,508,002 RAC: 20 |
Boeing's latest attempt: Boeing delays rerun of Starliner space capsule test wrote: ... The CST-100 Starliner will launch from Florida at some point to showcase how it can ferry crews to and from the International Space Station (ISS). Here's hoping that Boeing honestly truly have cleaned up their leopard spots... Fly safe folks! Martin See new freedom: Mageia Linux Take a look for yourself: Linux Format The Future is what We all make IT (GPLv3) |
ML1 Send message Joined: 25 Nov 01 Posts: 21325 Credit: 7,508,002 RAC: 20 |
A few days on and not looking good... Hilarious... If it wasn't all very real. See for yourself: (Try playing this at x1.5 speed unless you wish to savor the experience!) Boeing Blows it AGAIN!! Is this thing safe? What we should have done differently! wrote: ... we need an alternative to Starliner... no matter the cost. Boeing Starliner launch delayed again, and insane SpaceX Starship progress! wrote: 2 The Future I would imagine that the thrusters valves, ALL of 'em, are ALL 'Safety Critical'... Or why have them?... How does Boeing get away with such dangerous sloppy expensive silliness? Oh... And this is supposed to be 'Astronaut Rated'?! Fly safe folks!! Martin See new freedom: Mageia Linux Take a look for yourself: Linux Format The Future is what We all make IT (GPLv3) |
ML1 Send message Joined: 25 Nov 01 Posts: 21325 Credit: 7,508,002 RAC: 20 |
A few days on and not looking good... This is looking to be worryingly 'curious'... Boeing's Starliner sees August launch slipping away after more valve trouble wrote: ... Ooooer! That last sentence sounds like a "Bit of a telling off"! So... How has that come to pass and be so 'unexpected' so late before launch?... Fly safe folks!! Martin See new freedom: Mageia Linux Take a look for yourself: Linux Format The Future is what We all make IT (GPLv3) |
ML1 Send message Joined: 25 Nov 01 Posts: 21325 Credit: 7,508,002 RAC: 20 |
Moving back to a lower altitude for an update of recent Boeing safety news: Boeing 787 Dreamliner: A Timeline of Recent Production Problems wrote: ... A new defect on Boeing’s Dreamliner aircraft surfaced in July, the latest in a series of issues that arose late last summer. Deliveries of the popular plane are now halted, pressuring Boeing’s profits. WSJ’s Andrew Tangel explains how Boeing got here... FAA mandates inspections of Boeing 737 switches that could pose safety risk wrote: Oxygen levels could become "dangerously low" if switches fail over 10,000 feet... Boeing 737 MAX planes face cargo rules over fire-related concerns wrote: ... The Federal Aviation Administration (FAA) said all Boeing MAX planes and some other 737 models were affected by the precautionary measure... The pressure switch problem in particular is worrying for that having been something that isn't normally checked each flight and there is no other warning of failure and it took an actual airline themselves to discover the safety critical problem!... Fly safe?! Martin See new freedom: Mageia Linux Take a look for yourself: Linux Format The Future is what We all make IT (GPLv3) |
ML1 Send message Joined: 25 Nov 01 Posts: 21325 Credit: 7,508,002 RAC: 20 |
And after a bit more wiggling and waggling of whatever bits, we have: Boeing's Starliner launch could face delay of several months... wrote: Aug 12 (Reuters) - Boeing Co's (BA.N) Starliner space capsule launch could be delayed by several months as it will likely need to be removed from atop a rocket for repairs, the Wall Street Journal reported on Thursday, citing people familiar with the matter. Note how Boeing are keeping very quiet about why/how those valves are not working... Suspicious?... Embarrassing??... Safe???... Fly safe folks! Martin See new freedom: Mageia Linux Take a look for yourself: Linux Format The Future is what We all make IT (GPLv3) |
W-K 666 Send message Joined: 18 May 99 Posts: 19422 Credit: 40,757,560 RAC: 67 |
With that many valve failures, you have to say there is either a fundamental design fault or faulty construction. Either way Boeing should initiate investigations into both scenarios and not even consider a launch until the cause has been rectified, at their own expense. |
Gary Charpentier Send message Joined: 25 Dec 00 Posts: 31043 Credit: 53,134,872 RAC: 32 |
With that many valve failures, you have to say there is either a fundamental design fault or faulty construction. Different capsule than the one that flew the first failed mission. Obviously that one the valves did work. Faulty construction looks likely. Need to start looking into batch numbers and machine operators, assemblers, materials suppliers, etc. Entire mission is Boeing's cost, only NASA part will be ISS docking, think mission control salaries. |
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