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Fluid dynamics and combustion chambers. It's rocket science, a long, expensive trial-and-error development process. And unlike other sciences, most of the resul

Fluid dynamics and combustion chambers. It's rocket science, a long, expensive trial-and-error development process. And unlike other sciences, most of the results are never published so each entity has to recreate the foundations themselves. It takes money, time, and dedicated careers.

vasili111 10y ago
Why not to just buy one aircraft and reverse engineer its engines? What is the problem with just copying exact copy of existing engine?
- clintonb 10y ago
  In this case U.S. government restrictions probably restrict China from buying U.S.-manufactured planes. I doubt Antonov wants to sell its only An-225.
  - qaq 10y ago
    Antonov is selling the unfinished frame of second AN-225 and rights and documentation as far as I remember.
  - coredog64 10y ago
    The Chinese buy plenty of U.S. manufactured planes. In fact, in order to convince China to buy large aircraft like the 777, Boeing was more than happy to sign offset agreements[0] that sent a significant portion of manufacturing of smaller aircraft to Chinese subcontractors. Lest you think I would only throw stones at my former employer, Airbus has been doing that and more. They are actually doing final assembly in China. [0] https://en.wikipedia.org/wiki/Offset_agreement https://en.wikipedia.org/wiki/Offset_agreement
- avar 10y ago
  This thing is not exactly something you can just order online at http://www.antonov.com http://www.antonov.com Obviously if China wants to buy one the fact that they want to reverse engineer its technology is going to be patently obvious. Even if China could get a hold of an AN-225 reverse engineering one is a huge task, and at best you only know exactly what this hardware did, not what they avoided, or good ideas they didn't pursue purely due to resource constraints etc. So what happens instead is that a state like China approaches the Ukraine for a manufacturing agreement like the one described in the article. China hands over a lot of money which covers not just the planes but also the tech, and job are created in the Ukraine as a result.
- dogma1138 10y ago
  Because a lot of the "knowledge" comes from the engineering process much of it is trial and error and often it's not documented in the theoretical books ;) This is why it's easy to lose the ability to produce something e.g. the big rockets that NASA used to make. China can make a copy of the engine but it would not gain sufficient insight into why they chosen to design it exactly as it did so making adjustments would not be very easy or possible at all without putting almost as much R&D effort into it as making a whole new engine from scratch and debugging things would also be near impossible. There is a reason why there are only a few engine manufacturers in the world, it's very hard work, and as far as big engines go then only RR and GE are really in the game.
  - DashRattlesnake 10y ago
    > This is why it's easy to lose the ability to produce something e.g. the big rockets that NASA used to make. IIRC, to avoid this when they shut down F-22 production, they crated a huge number of DVDs documenting every step of the manufacturing process, so that knowledge wouldn't be totally lost.
- rayiner 10y ago
  Modern turbofans only stand up to their extreme operating conditions because of the use of exotic alloys and elaborate cooling techniques. Just because you know what shape a turbine blade should be doesn't mean you can copy the exotic alloy and manufacture it in a way that results in the correct crystal structure.
  - semi-extrinsic 10y ago
    Not only exotic alloys, but single crystal blades. That's right, the blade is machined out of a single atomistically perfect crystal with no defects what so ever. The main point is that this reduces thermal creep, meaning you can have tighter tolerances and more power/efficiency.
    - rayiner 10y ago
      Also, because combustion temperatures can exceed the melting point of the alloy, HPT blades often have a complex set of internal hollows and holes at the surface for cooling air. Air can be passed through to create a boundary layer on the surface that prevents the surface from heating up past the melting point of the alloy.
    - dmoy 10y ago
      Holy crap that is nuts. Towards the middle/end in here: https://www.theengineer.co.uk/issues/june-2015-online/jewel-in-the-crown-rolls-royces-single-crystal-turbine-blade-casting-foundry/ https://www.theengineer.co.uk/issues/june-2015-online/jewel-... Also cool to hear them talking about automating as much stuff as possible to remove human error. Incidentally that's also how we go about software release processes where I work.
    - Osmium 10y ago
      > single atomistically perfect crystal with no defects what so ever Nit-pick, but single crystals can (and do) still have defects. Your point about single crystal turbine blades being awesome I agree with completely though :)
- hourislate 10y ago
  I'm not an expert in the field of reverse engineering but I have read in the past that it can be extremely difficult and end up costing more in time, effort, money than designing from scratch. China has the luxury of being able to play catch up by purchasing technology. Why spend the next 20 years trying to develop it when you can pay Ukraine who already has the expertise/product and probably gave the Chinese a deal. It's just smart business. China apparently did something similar with BMW. They bought a BMW factory in Brazil (I think) for a couple of billion and disassembled it piece by piece and moved it to China. It saved them years of figuring out the how to of high tech auto engine manufacturing. Link to Story: http://tech.mit.edu/V126/N4/4long4.html http://tech.mit.edu/V126/N4/4long4.html

vasili111 10y ago

Why not to just buy one aircraft and reverse engineer its engines? What is the problem with just copying exact copy of existing engine?

clintonb 10y ago
In this case U.S. government restrictions probably restrict China from buying U.S.-manufactured planes. I doubt Antonov wants to sell its only An-225.
- qaq 10y ago
  Antonov is selling the unfinished frame of second AN-225 and rights and documentation as far as I remember.
- coredog64 10y ago
  The Chinese buy plenty of U.S. manufactured planes. In fact, in order to convince China to buy large aircraft like the 777, Boeing was more than happy to sign offset agreements[0] that sent a significant portion of manufacturing of smaller aircraft to Chinese subcontractors. Lest you think I would only throw stones at my former employer, Airbus has been doing that and more. They are actually doing final assembly in China. [0] https://en.wikipedia.org/wiki/Offset_agreement https://en.wikipedia.org/wiki/Offset_agreement
avar 10y ago
This thing is not exactly something you can just order online at http://www.antonov.com http://www.antonov.com Obviously if China wants to buy one the fact that they want to reverse engineer its technology is going to be patently obvious. Even if China could get a hold of an AN-225 reverse engineering one is a huge task, and at best you only know exactly what this hardware did, not what they avoided, or good ideas they didn't pursue purely due to resource constraints etc. So what happens instead is that a state like China approaches the Ukraine for a manufacturing agreement like the one described in the article. China hands over a lot of money which covers not just the planes but also the tech, and job are created in the Ukraine as a result.
dogma1138 10y ago
Because a lot of the "knowledge" comes from the engineering process much of it is trial and error and often it's not documented in the theoretical books ;) This is why it's easy to lose the ability to produce something e.g. the big rockets that NASA used to make. China can make a copy of the engine but it would not gain sufficient insight into why they chosen to design it exactly as it did so making adjustments would not be very easy or possible at all without putting almost as much R&D effort into it as making a whole new engine from scratch and debugging things would also be near impossible. There is a reason why there are only a few engine manufacturers in the world, it's very hard work, and as far as big engines go then only RR and GE are really in the game.
- DashRattlesnake 10y ago
  > This is why it's easy to lose the ability to produce something e.g. the big rockets that NASA used to make. IIRC, to avoid this when they shut down F-22 production, they crated a huge number of DVDs documenting every step of the manufacturing process, so that knowledge wouldn't be totally lost.
rayiner 10y ago
Modern turbofans only stand up to their extreme operating conditions because of the use of exotic alloys and elaborate cooling techniques. Just because you know what shape a turbine blade should be doesn't mean you can copy the exotic alloy and manufacture it in a way that results in the correct crystal structure.
- semi-extrinsic 10y ago
  Not only exotic alloys, but single crystal blades. That's right, the blade is machined out of a single atomistically perfect crystal with no defects what so ever. The main point is that this reduces thermal creep, meaning you can have tighter tolerances and more power/efficiency.
  - rayiner 10y ago
    Also, because combustion temperatures can exceed the melting point of the alloy, HPT blades often have a complex set of internal hollows and holes at the surface for cooling air. Air can be passed through to create a boundary layer on the surface that prevents the surface from heating up past the melting point of the alloy.
  - dmoy 10y ago
    Holy crap that is nuts. Towards the middle/end in here: https://www.theengineer.co.uk/issues/june-2015-online/jewel-in-the-crown-rolls-royces-single-crystal-turbine-blade-casting-foundry/ https://www.theengineer.co.uk/issues/june-2015-online/jewel-... Also cool to hear them talking about automating as much stuff as possible to remove human error. Incidentally that's also how we go about software release processes where I work.
  - Osmium 10y ago
    > single atomistically perfect crystal with no defects what so ever Nit-pick, but single crystals can (and do) still have defects. Your point about single crystal turbine blades being awesome I agree with completely though :)
hourislate 10y ago
I'm not an expert in the field of reverse engineering but I have read in the past that it can be extremely difficult and end up costing more in time, effort, money than designing from scratch. China has the luxury of being able to play catch up by purchasing technology. Why spend the next 20 years trying to develop it when you can pay Ukraine who already has the expertise/product and probably gave the Chinese a deal. It's just smart business. China apparently did something similar with BMW. They bought a BMW factory in Brazil (I think) for a couple of billion and disassembled it piece by piece and moved it to China. It saved them years of figuring out the how to of high tech auto engine manufacturing. Link to Story: http://tech.mit.edu/V126/N4/4long4.html http://tech.mit.edu/V126/N4/4long4.html