8th Jan 2014, 08:23
permalink Post: 1771
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| The problem with software systems is that [...] you cannot prove them to be correct |
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| hence the triplication, heavy emphasis on configuration control and high cost. |
9th Jan 2014, 01:07
permalink Post: 1772
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Originally Posted by
msbbarratt
Safety critical analogue control systems are far easier to maintain and repair over extended periods of time than their digital equivalents.
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| There's also no need for triplication for a start, at least not from the point of view establishing correct system output. |
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| All that an analogue control system is doing is implementing a series of differential equations. |
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| The problem with software systems is that they're way too complex |
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| Analogue control circuits are also largely immune to component selection ... a capacitor is still a capacitor. Obsolescence is a significantly reduced problem. |
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| We won't be seeing A380s, etc. flying once the spares run out. |
25th Jul 2014, 03:35
permalink Post: 1824
I just have a problem with studies that try to analyze human activities with reductionist statistics and math. Most of human achievement comes not from the masses (which perhaps can be studied that way) but from the outliers, the screwballs, the few who, through enhanced human cussedness and stubbornness, decide NOT to stay with the obvious, efficient or safe thing.
Concorde was a political animal, heavily subsidized because someone want it to happen, regardless of efficiency.
But then, ALL advances in transportation have been - and often still are - political animals, subsidized because someone with money and power wants it to happen, regardless of efficiency.
Columbus and Magellan were subsidized, to head straight out to sea when everyone else was sticking close to the coastlines. Look up the land grants to U.S. trans-continental railroads. Or the Air Mail contracts that supported the fledgling American air transport industry (and if you think "that was then, and this is now," - consider the budget of the FAA and NTSB and TSA, and the military contracts to Boeing and its suppliers.)
Cars? Consider how much tax money goes to build and maintain highway systems.
And consider the man who stood up in the U.S. Capitol and declared, "I believe that this nation should commit itself to achieving the goal, before this decade is out, of landing a man on the moon and returning him safely to the earth."
Concorde failed because it lost political support** - just like Apollo and the Space Shuttle. But most of the other aircraft on those charts would also be, or have been, far rarer in the skies (or never appeared) if they lost (or never had) their own political backing and subsidies, direct and indirect.
**If the French government had felt it was in France's interest for Concorde to continue, I'm sure money for, and political pressure on, Airbus would have been found to keep her flying.
And Concorde also faced substantial political opposition - its market viability would have been much higher if U.S. authorities had been as lenient with its "furrin" sonic booms as they had been with our own home-grown booms ("The Sound of Freedom!", it was called.)
Now - Concorde's technology was pushing 40, and no doubt that particular airframe would have faded away, just like the 727 and the other designs from the 1960's. To be replaced with something newer. But the future of supersonic transport in general was cut short not because of some statistical failing, but simply because it no longer shared the same political support as subsonic aviation.
Concorde was a political animal, heavily subsidized because someone want it to happen, regardless of efficiency.
But then, ALL advances in transportation have been - and often still are - political animals, subsidized because someone with money and power wants it to happen, regardless of efficiency.
Columbus and Magellan were subsidized, to head straight out to sea when everyone else was sticking close to the coastlines. Look up the land grants to U.S. trans-continental railroads. Or the Air Mail contracts that supported the fledgling American air transport industry (and if you think "that was then, and this is now," - consider the budget of the FAA and NTSB and TSA, and the military contracts to Boeing and its suppliers.)
Cars? Consider how much tax money goes to build and maintain highway systems.
And consider the man who stood up in the U.S. Capitol and declared, "I believe that this nation should commit itself to achieving the goal, before this decade is out, of landing a man on the moon and returning him safely to the earth."
Concorde failed because it lost political support** - just like Apollo and the Space Shuttle. But most of the other aircraft on those charts would also be, or have been, far rarer in the skies (or never appeared) if they lost (or never had) their own political backing and subsidies, direct and indirect.
**If the French government had felt it was in France's interest for Concorde to continue, I'm sure money for, and political pressure on, Airbus would have been found to keep her flying.
And Concorde also faced substantial political opposition - its market viability would have been much higher if U.S. authorities had been as lenient with its "furrin" sonic booms as they had been with our own home-grown booms ("The Sound of Freedom!", it was called.)
Now - Concorde's technology was pushing 40, and no doubt that particular airframe would have faded away, just like the 727 and the other designs from the 1960's. To be replaced with something newer. But the future of supersonic transport in general was cut short not because of some statistical failing, but simply because it no longer shared the same political support as subsonic aviation.
25th Feb 2016, 13:01
permalink Post: 1931
Tiny Items
Hi Dear Guys,
Amazing thread on an amazing aircraft! Red through all the posts. What an immense amount of knowledge/experience on this bird! Your valuable inputs triggerd my curiousity to the extent that I have started to study Concorde manuals trying to understand systems and operating details. Not an easy job! I think a more detailed Traning Manual would help me greatly.
Here is my question:
Going through the FM exterior inspection chapter I have run into tiny details what are really hard to find even on close-up external photos. Just to name a few: "nose gear free fall dump valve vent", "engine oil tank vent" or "hydraulic-driven fuel transfer pump drain". Was there a "pictorial" external inspection guide available on the Concorde for crew training (similar to Boeing or Airbus training aids)? If yes, could somehow, somebody send me a copy of that?
Appreciate your help,
Tamas
Amazing thread on an amazing aircraft! Red through all the posts. What an immense amount of knowledge/experience on this bird! Your valuable inputs triggerd my curiousity to the extent that I have started to study Concorde manuals trying to understand systems and operating details. Not an easy job! I think a more detailed Traning Manual would help me greatly.
Here is my question:
Going through the FM exterior inspection chapter I have run into tiny details what are really hard to find even on close-up external photos. Just to name a few: "nose gear free fall dump valve vent", "engine oil tank vent" or "hydraulic-driven fuel transfer pump drain". Was there a "pictorial" external inspection guide available on the Concorde for crew training (similar to Boeing or Airbus training aids)? If yes, could somehow, somebody send me a copy of that?
Appreciate your help,
Tamas