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Nice to hear. Concorde was a beautiful airplane, but limited to '60s technology (it even had vacuum tubes in the flight deck computers). But it did pave the w

Nice to hear. Concorde was a beautiful airplane, but limited to '60s technology (it even had vacuum tubes in the flight deck computers). But it did pave the way for a lot of technological advances at that time, such as carbon brakes etc. Be good to see what engineers can come up with using current technology to make things stronger, faster and lighter. Always intrigued by the fluctuations in the airline industry. I remember a time when it was said 'smaller aircraft were dead, and it is the time of the super jumbos', and now the reverse is true with airlines shunning huge aircraft for smaller aircraft that can do regional hops. Given that the R&D and deployment process for a new aircraft type is measured over decades, it would be incredibly difficult to build a plane today that will fit the market in 10 years time. Hats off to Boeing, Airbus, Embraer et al for their efforts.

agumonkey 10y ago
They never replaced the computers with transistors ?
- cyberferret 10y ago
  They did on most of the flight systems, but I believe I read somewhere that even on their retirement date, many of the aircraft still had tubes in the avionics bays. A complete replacement programme was just too expensive, and what they had worked, so they stuck with it. Had Concorde been a profitable aircraft, then it might have been a different story...
- Baeocystin 10y ago
  I'm not saying this was necessarily true for the Concorde, but sometimes you really do need a vacuum tube. All commercial x-ray sources use tubes, for example. The magnetrons that power our microwave ovens are vacuum tube oscillators. And by their nature, tubes are much faster than semiconductors, which has its uses.
  - foobar__ 10y ago
    Where are tubes faster than semiconductors?
    - Baeocystin 10y ago
      http://spectrum.ieee.org/semiconductors/devices/introducing-the-vacuum-transistor-a-device-made-of-nothing http://spectrum.ieee.org/semiconductors/devices/introducing-... http://www.sciencemag.org/news/2012/05/return-vacuum-tube http://www.sciencemag.org/news/2012/05/return-vacuum-tube These links will get you started.
      - foobar__ 10y ago
        These articles don't say that regular tubes are faster than transistors, only that "vacuum-channel transistors" (nano-scale devices inspired by tubes but different) could possibly eventually be faster than semiconductors. But these articles are from 2014 and 2012 and they contradict easily looked up facts. The 2012 article claims that this technology promises speeds of up to 460GHz, which seems to have already been topped by regular semiconductor transistors, even by 2003: See https://en.wikipedia.org/wiki/Milton_Feng#World.27s_fastest_transistor https://en.wikipedia.org/wiki/Milton_Feng#World.27s_fastest_... for a really old example. So to me it seems that this research is in a very early stage and no one knows whether the finished product (if it is ever finished) will be faster than semiconductors. Of course the researchers working on this must make big promises or they wouldn't get grants, but that's how the grant system works today, and it doesn't tell you anything about how viable the product is. edit: Not to sound to negative here, I am really looking forward to this new technology and hope it will turn out alright. But it looks very much like fundamental research, so I take issue with broad claims like "by their nature, tubes are much faster than semiconductors, which has its uses", when apparently nothing has left the laboratory yet.
        Baeocystin 10y ago
        I appreciate the links. Here's a more recent link, specifically regarding terahertz research, you might find interesting. http://iopscience.iop.org/article/10.1088/1361-6463/50/4/043001 http://iopscience.iop.org/article/10.1088/1361-6463/50/4/043... I want to emphasize an important distinction: that vacuum-based amps have higher potential switching speeds than semiconductors is not a novel thing, nor is it early stage research. It is part and parcel of the nature of semiconductors. What is cutting-edge is miniaturization of vacuum-based systems using conventional fab processes. That's the exciting stuff!
- parados 10y ago
  They always used transistors[0]. Early models had analogue computers, some digital stuff crept in over its service life. [0] https://paulross.github.io/pprune-concorde/docs/AICU_-Air_Intake_Control_Computer-0.html https://paulross.github.io/pprune-concorde/docs/AICU_-Air_In...
- mikeash 10y ago
  With only twelve operating aircraft, it's hard to justify substantial engineering expense for upgrades.
  - agumonkey 10y ago
    Sure, but things changed so fast in this era .. 30 years in operation.
Accacin 10y ago
Someone linked to this forum thread on another HN post: http://www.pprune.org/tech-log/423988-concorde-question.html http://www.pprune.org/tech-log/423988-concorde-question.html It's incredible interesting and various pilots and engineers turn up to share their stories.
- cyberferret 10y ago
  That is a magic thread on pprune. TONS of great info about the aircraft, and some really technical insights by guys who flew the things too. Warning: Grab a LARGE cup of coffee and bag of popcorn and be prepared to lose many hours reading through that (massive) 99 page thread.
- parados 10y ago
  That thread is re-mixed here, by subject, for your reading pleasure: https://paulross.github.io/pprune-concorde/docs/index.html https://paulross.github.io/pprune-concorde/docs/index.html
- rwmj 10y ago
  If you like that thread, I can really recommend this book: Concorde New Shape in the Sky by Kenneth Owen. There are two editions of the book. The first edition is super cheap (eg. 29p + postage: https://www.amazon.co.uk/d/cka/Concorde-New-Shape-Sky-Ken-Owen/0710602138 https://www.amazon.co.uk/d/cka/Concorde-New-Shape-Sky-Ken-Ow...). There was a second edition written after the 2000 accident in France, which is supposed to be a better version, but I have not read it because it's out of print and considerably more expensive.
  - theoh 10y ago
    That is a very interesting book. Two things I remember: the statement that by the end of the engineering effort "everyone was exhausted and nobody was really in control" (paraphrasing slightly from memory) and a curious interview with a (British) engineer who was very concerned about keeping technologies proprietary at the national level--he seemed to be happy for UK firms to share know-how (as I believe is traditional, up to a point, in engineering culture) but god forbid it should be shared with another country's engineers. Shades of the Brexit mentality.

agumonkey 10y ago

They never replaced the computers with transistors ?

cyberferret 10y ago
They did on most of the flight systems, but I believe I read somewhere that even on their retirement date, many of the aircraft still had tubes in the avionics bays. A complete replacement programme was just too expensive, and what they had worked, so they stuck with it. Had Concorde been a profitable aircraft, then it might have been a different story...
Baeocystin 10y ago
I'm not saying this was necessarily true for the Concorde, but sometimes you really do need a vacuum tube. All commercial x-ray sources use tubes, for example. The magnetrons that power our microwave ovens are vacuum tube oscillators. And by their nature, tubes are much faster than semiconductors, which has its uses.
- foobar__ 10y ago
  Where are tubes faster than semiconductors?
  - Baeocystin 10y ago
    http://spectrum.ieee.org/semiconductors/devices/introducing-the-vacuum-transistor-a-device-made-of-nothing http://spectrum.ieee.org/semiconductors/devices/introducing-... http://www.sciencemag.org/news/2012/05/return-vacuum-tube http://www.sciencemag.org/news/2012/05/return-vacuum-tube These links will get you started.
    - foobar__ 10y ago
      These articles don't say that regular tubes are faster than transistors, only that "vacuum-channel transistors" (nano-scale devices inspired by tubes but different) could possibly eventually be faster than semiconductors. But these articles are from 2014 and 2012 and they contradict easily looked up facts. The 2012 article claims that this technology promises speeds of up to 460GHz, which seems to have already been topped by regular semiconductor transistors, even by 2003: See https://en.wikipedia.org/wiki/Milton_Feng#World.27s_fastest_transistor https://en.wikipedia.org/wiki/Milton_Feng#World.27s_fastest_... for a really old example. So to me it seems that this research is in a very early stage and no one knows whether the finished product (if it is ever finished) will be faster than semiconductors. Of course the researchers working on this must make big promises or they wouldn't get grants, but that's how the grant system works today, and it doesn't tell you anything about how viable the product is. edit: Not to sound to negative here, I am really looking forward to this new technology and hope it will turn out alright. But it looks very much like fundamental research, so I take issue with broad claims like "by their nature, tubes are much faster than semiconductors, which has its uses", when apparently nothing has left the laboratory yet.
      - Baeocystin 10y ago
        I appreciate the links. Here's a more recent link, specifically regarding terahertz research, you might find interesting. http://iopscience.iop.org/article/10.1088/1361-6463/50/4/043001 http://iopscience.iop.org/article/10.1088/1361-6463/50/4/043... I want to emphasize an important distinction: that vacuum-based amps have higher potential switching speeds than semiconductors is not a novel thing, nor is it early stage research. It is part and parcel of the nature of semiconductors. What is cutting-edge is miniaturization of vacuum-based systems using conventional fab processes. That's the exciting stuff!
parados 10y ago
They always used transistors[0]. Early models had analogue computers, some digital stuff crept in over its service life. [0] https://paulross.github.io/pprune-concorde/docs/AICU_-Air_Intake_Control_Computer-0.html https://paulross.github.io/pprune-concorde/docs/AICU_-Air_In...
mikeash 10y ago
With only twelve operating aircraft, it's hard to justify substantial engineering expense for upgrades.
- agumonkey 10y ago
  Sure, but things changed so fast in this era .. 30 years in operation.

Accacin 10y ago

Someone linked to this forum thread on another HN post: http://www.pprune.org/tech-log/423988-concorde-question.html http://www.pprune.org/tech-log/423988-concorde-question.html It's incredible interesting and various pilots and engineers turn up to share their stories.

cyberferret 10y ago
That is a magic thread on pprune. TONS of great info about the aircraft, and some really technical insights by guys who flew the things too. Warning: Grab a LARGE cup of coffee and bag of popcorn and be prepared to lose many hours reading through that (massive) 99 page thread.
parados 10y ago
That thread is re-mixed here, by subject, for your reading pleasure: https://paulross.github.io/pprune-concorde/docs/index.html https://paulross.github.io/pprune-concorde/docs/index.html
rwmj 10y ago
If you like that thread, I can really recommend this book: Concorde New Shape in the Sky by Kenneth Owen. There are two editions of the book. The first edition is super cheap (eg. 29p + postage: https://www.amazon.co.uk/d/cka/Concorde-New-Shape-Sky-Ken-Owen/0710602138 https://www.amazon.co.uk/d/cka/Concorde-New-Shape-Sky-Ken-Ow...). There was a second edition written after the 2000 accident in France, which is supposed to be a better version, but I have not read it because it's out of print and considerably more expensive.
- theoh 10y ago
  That is a very interesting book. Two things I remember: the statement that by the end of the engineering effort "everyone was exhausted and nobody was really in control" (paraphrasing slightly from memory) and a curious interview with a (British) engineer who was very concerned about keeping technologies proprietary at the national level--he seemed to be happy for UK firms to share know-how (as I believe is traditional, up to a point, in engineering culture) but god forbid it should be shared with another country's engineers. Shades of the Brexit mentality.