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None of those are single points of failure.
Airbus A320 Crashes in Alps
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None of those are single points of failure.
Helios was an interesting one. The aircraft in question there was a Boeing 737-300 which uses a an identical overhead panel to all 737's since the 1960's. It's pretty crude but shows all the info what is needed.
The problem with Helios was that the engineers forgot to switch the outflow valve (pressurisation is controlled by airflow out, not in) to manual, mistake 1
The pilots then forgot to check it on the pre-flights and never switched it to auto. It's one of these things which is only put in manual when you've got a fault so over familiarity can cause people to skip things. Mistake 2
The pilots didn't check the pressurisation panel passing FL100, a standard check to make sure the cabin pressure is increasing and differential pressure is correct passing 10,000ft. Mistake 3
The pilots are alerted by a buzzer in the cockpit saying cabin altitude was too high. The problem is with Boeing and their infinite wisdom, the noise is exactly the same as the takeoff config warning (sounds when thrust goes above 60% when flaps not set, parking brakes on etc etc). So they then spend time trying to fault find why the takeoff config is sounding in the air, without thinking to look as the OHP. Mistake 4
Pilots lack of awareness of the affects of hypoxia become apparent and both pass out at the controls. In the mean time the pax in the back are all sitting pretty with their masks on. Aircraft levels out in cruise as directed by autopilot. Plane flies until runs out of fuel, starts descending and impacts terrain.
Scary thoughts, but a great example of becoming fixated on one problem (the cause of many accidents, read into United Airlines flight 173) rather than the wider picture, lack of crew training and a list of errors which caused the death of 121 persons.
A crash in aviation isn't just about pointing fingers and saying "whodunnit", every time there is an accident there are improvements. The 737 now has cabin altitude lights that illuminate at eye level when the cabin pressure drops too much, rather than just one on the overhead panel. United 173 (http://en.wikipedia.org/wiki/United_Airlines_Flight_173) resulted in the concept of Crew Resource Management, the fundamentals of multi crew flying to this day.
Crashes are awful in aviation due to the lives lost, but from every crash there is an improvement or change to make sure it doesn't happen again, within the realms of a humans ability!
The problem with Helios was that the engineers forgot to switch the outflow valve (pressurisation is controlled by airflow out, not in) to manual, mistake 1
The pilots then forgot to check it on the pre-flights and never switched it to auto. It's one of these things which is only put in manual when you've got a fault so over familiarity can cause people to skip things. Mistake 2
The pilots didn't check the pressurisation panel passing FL100, a standard check to make sure the cabin pressure is increasing and differential pressure is correct passing 10,000ft. Mistake 3
The pilots are alerted by a buzzer in the cockpit saying cabin altitude was too high. The problem is with Boeing and their infinite wisdom, the noise is exactly the same as the takeoff config warning (sounds when thrust goes above 60% when flaps not set, parking brakes on etc etc). So they then spend time trying to fault find why the takeoff config is sounding in the air, without thinking to look as the OHP. Mistake 4
Pilots lack of awareness of the affects of hypoxia become apparent and both pass out at the controls. In the mean time the pax in the back are all sitting pretty with their masks on. Aircraft levels out in cruise as directed by autopilot. Plane flies until runs out of fuel, starts descending and impacts terrain.
Scary thoughts, but a great example of becoming fixated on one problem (the cause of many accidents, read into United Airlines flight 173) rather than the wider picture, lack of crew training and a list of errors which caused the death of 121 persons.
A crash in aviation isn't just about pointing fingers and saying "whodunnit", every time there is an accident there are improvements. The 737 now has cabin altitude lights that illuminate at eye level when the cabin pressure drops too much, rather than just one on the overhead panel. United 173 (http://en.wikipedia.org/wiki/United_Airlines_Flight_173) resulted in the concept of Crew Resource Management, the fundamentals of multi crew flying to this day.
Crashes are awful in aviation due to the lives lost, but from every crash there is an improvement or change to make sure it doesn't happen again, within the realms of a humans ability!
I would love to elaborate on why you are wrong, but I work in aircraft maintenance and many of my colleagues use this site and for the sake of my job or people thinking I was talking about my own airline I just deleted the 500 word post I was about to makeI wouldn't want a link to be made wrongly that cost me my job
No it doesn't. Which is why you have an accountable manager at an airline. Not only the man furthest back carries the can. After all look at who is and isn't in prison for the helios incident. If the man on the tools so to speak hasn't been properly trained and supported he won't be the man in jail.
I worked with the man that signed off the Helios flight and was the engineer on the radio when it all happened. I pray I never have to go through what he did for years. I hope I'm never in the shoes of these people that worked on the German Wings aircraft. It's bad enough for the anxiety mislaying a tool for a few hours let alone losing that many lives.
Not that relevant really with so much maintenance done at night these days, it could have been the first leg of the day. Also nothing to say it has to fail straight after maintenance.
They did, you can't monitor for a pair of pilots badly trained.
This is why you're an engineer and I am not. I was lead to believe that accidents go back as far as possible but didn't consider training and manager structure. I stand corrected and apologise for my incorrect information.
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Indeed, very interesting and always good to cut through the media trash.
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Good posts FL630, thanks for taking the time to write them.
[TW]Fox;27820717 said:
Bird strike or foreign object in to an engine? How is that not a single point?
What about the effect of a failed rudder causing a plane to ditch and spin, caused by aggressive pilot rudder
movements
Cause and effect
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Because commercial passenger airliners have at least two engines?
A single engine failure doesn't mean that an aircraft will suddenly plummet ouf of the skies like a stone. They still have their momentum to carry them a bit forward and pilots are generally trained to use flaps / ailerons combined with the remaining engine (s) to generate forward motion to keep the plane airborne until such time that it is possible to land safely.
As for the engineering thing, a friend of mine is an aircraft technician for SAA and some of the stories he's told me would easily make some folks never want to fly again.
Like on one occasion using a hydraulic system from a completely different aircraft to power some or other moving bits, but only on one wing. The other wing had all the original gubbins, so they relied on the on-board systems to keep the aircraft stable during a long haul flight as the two systems had completely different calibration parameters.
I know that, but the outcome has unknown variables, it could go either way. You could navigate to a nearest airport, land in the Hudson, or have no variable terrain to land safely on.
I do know how aircraft function
The fact I'm trying to point out is saying will never be a single point of failure is a pretty bold statement, its unlikely to be a single point, but not never
Like in my other example
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The only single point of failure I can think of is a bomb or human error.
Double bird strikes like the Hudson can almost be discounted due to their freak nature, it's the only one I know of in modern commercial aviation history.
Double bird strikes like the Hudson can almost be discounted due to their freak nature, it's the only one I know of in modern commercial aviation history.
With a twinjet aircraft and a single failed engine the outcome is 99.999999999999999999999999999% of the time 'The plane lands and everyone is peeved about the delay'.
Then you'll know how silly it is to suggest that a fatal accident as a result of only one single factor is almost unheard of.
In this very vague story that I don't believe (from his point not yours), if your friend didn't report this to the authorities he's the biggest ****ing idiot in the whole tale. A disgrace to the industry if he can fit non approved parts to an aircraft and let it fly. Next time you see said friend, tell him he's a buffoon that has no place near an aircraft. I sincerely hope this chimp is not a licensed engineer.
Hah! GHEY
No, it's not. An aircraft receives some sort of maintenance before every take off
how plausible is this - the cabin depressurizes for whatever reason, the aircraft starts to descend immediately as you'd want it to do with a depressurized cabin... but unfortunately the mountainous terrain poses a bit of a problem with this immediate descent?
Would a plane automatically descend upon detecting that the cabin pressure had dropped or is it left to the pilots? If it does then how well does it take into account the terrain when performing this rapid descent?
Would a plane automatically descend upon detecting that the cabin pressure had dropped or is it left to the pilots? If it does then how well does it take into account the terrain when performing this rapid descent?
furthermore birds don't tend to fly at 38,000ft. They do get bloody close though. I was surprise to read the max altitudes for some:
http://en.wikipedia.org/wiki/List_of_birds_by_flight_heights