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That is exactly what I thought as well. On the one hand, that makes a lot of sense as in, "Let's build a supersonic platform based on one that we know works to

That is exactly what I thought as well. On the one hand, that makes a lot of sense as in, "Let's build a supersonic platform based on one that we know works to prove to ourselves that we can actually build a supersonic plane." But the marketing spin around "Hey we made a copy of this plane that was built 60 years ago and we think it will work." Just doesn't have the same flair :-) Still, as NASA has shown time and again, if you have a reliable air frame that is well characterized, and you instrument the crap out of it, then you can set it up a wide variety of aeronautical experiments and collect really valuable data that feels more trustworthy then "theoretical results" from a 10K core parallel computer doing CFD analysis. If they are smart (and we can presume they are) they are doing both and updating their CFD models with data from XB-1 so that they are more confident that Overture will work. That said, to be really "ground breaking" they really should use the "low boom" technology that NASA has been researching to make a plane that can fly supersonic over land. That would actually be a new spin on the old Concorde business plan where it opens up more routes. Just the "hey it will be cheaper" bet doesn't leave a lot of room for an assumption fail late in the certification process.

tobinfricke 6y ago
One difference is that huge strides have been made in materials research. Boom advertises extensive use of carbon fiber, which was not available when the X-3 was designed/built.
- ChuckMcM 6y ago
  Agreed, and it will be super helpful to see how carbon fiber deals with supersonic shock waves compared to steel. Like I said, it makes a lot of sense to build a platform that can prove that your tooling gets you to a working aircraft. And once you can do that, you can then iterate using the platform to inform your engineering choices. SpaceX has done this brilliantly and is the current poster child AFAICT. So I'm looking forward to the test program to see how it does, but was chuckling at the over the top marketing speak with which they "rolled out" this revolution. Step 1: Build a plane (check!) Step 2: Fly the plane (next on the list)
  - tobinfricke 6y ago
    I'd guess carbon fiber is replacing aluminum. I'm not a materials guy but it's hard to imagine replacing titanium with carbon fiber. I don't think steel is used much in aircraft. > So I'm looking forward to the test program to see how it does, but was chuckling at the over the top marketing speak with which they "rolled out" this revolution. Same! :-) I'm even more skeptical of their use of the word "sustainable," although I commend them on making that a goal.
    - deleted 6y ago
      [deleted]
    - vkou 6y ago
      > I don't think steel is used much in aircraft. It's not, but there's a very conspicuous counter-example - developed in the USSR. https://en.wikipedia.org/wiki/Mikoyan-Gurevich_MiG-25 https://en.wikipedia.org/wiki/Mikoyan-Gurevich_MiG-25 - with only 9% titanium content, compared to 26% of the F-15. For a number of economic and engineering reasons, instead of making jets out of titanium, the USSR, for the most part, preferred to export it to the US, in exchange for dollars.
      - tim333 6y ago
        The MiG-25 was unusual in that it was designed to go mach 2.8+ which overheats normal materials. Boom said they were limiting their design to mach 2.2 so as to be able to stick to normal safety approved stuff. It's interesting to see the Mig-25 steel design come back pretty much in SpaceX's starship.
nl 6y ago
This seems overstated. The X-3 and XB-1 both have long noses, and the similarities end there. The wing shapes are completely different, the engine intakes are configured differently, the tail is completely different etc. In terms of similarities, it looks more like an X-59 to me: https://www.nasa.gov/aeroresearch/nasa-marks-continued-progress-on-x-59 https://www.nasa.gov/aeroresearch/nasa-marks-continued-progr...
- ChuckMcM 6y ago
  Lots of differences with the x-59, no wing canards, one engine on the x-59 vs 3 on the XB-1, the XB-1 seems much shorter. On the plus side the X-59 was developed by Lockheed and one of their advisors, Dr. Johnson was a CTO at Lockheed so there could be some cross pollination there. That said, its kind of picking nits. If everything's a remix[1] is true, that is even MORE true in aviation. [1] https://www.youtube.com/watch?v=nJPERZDfyWc https://www.youtube.com/watch?v=nJPERZDfyWc
  - nl 6y ago
    > Lots of differences with the x-59, no wing canards, one engine on the x-59 vs 3 on the XB-1, the XB-1 seems much shorter. Um yeah of course? My point was the the long nose + wing shape (which defines much of the aerodynamics) is much more similar than the X-3 where the wing shape is completely different. See pics here: https://www.nasa.gov/centers/armstrong/news/FactSheets/FS-077-DFRC.html https://www.nasa.gov/centers/armstrong/news/FactSheets/FS-07... (Also hopefully the XB-1 is much better than the X-3 which was not a great plane!)

tobinfricke 6y ago

One difference is that huge strides have been made in materials research. Boom advertises extensive use of carbon fiber, which was not available when the X-3 was designed/built.

ChuckMcM 6y ago
Agreed, and it will be super helpful to see how carbon fiber deals with supersonic shock waves compared to steel. Like I said, it makes a lot of sense to build a platform that can prove that your tooling gets you to a working aircraft. And once you can do that, you can then iterate using the platform to inform your engineering choices. SpaceX has done this brilliantly and is the current poster child AFAICT. So I'm looking forward to the test program to see how it does, but was chuckling at the over the top marketing speak with which they "rolled out" this revolution. Step 1: Build a plane (check!) Step 2: Fly the plane (next on the list)
- tobinfricke 6y ago
  I'd guess carbon fiber is replacing aluminum. I'm not a materials guy but it's hard to imagine replacing titanium with carbon fiber. I don't think steel is used much in aircraft. > So I'm looking forward to the test program to see how it does, but was chuckling at the over the top marketing speak with which they "rolled out" this revolution. Same! :-) I'm even more skeptical of their use of the word "sustainable," although I commend them on making that a goal.
  - deleted 6y ago
    [deleted]
  - vkou 6y ago
    > I don't think steel is used much in aircraft. It's not, but there's a very conspicuous counter-example - developed in the USSR. https://en.wikipedia.org/wiki/Mikoyan-Gurevich_MiG-25 https://en.wikipedia.org/wiki/Mikoyan-Gurevich_MiG-25 - with only 9% titanium content, compared to 26% of the F-15. For a number of economic and engineering reasons, instead of making jets out of titanium, the USSR, for the most part, preferred to export it to the US, in exchange for dollars.
    - tim333 6y ago
      The MiG-25 was unusual in that it was designed to go mach 2.8+ which overheats normal materials. Boom said they were limiting their design to mach 2.2 so as to be able to stick to normal safety approved stuff. It's interesting to see the Mig-25 steel design come back pretty much in SpaceX's starship.

nl 6y ago

This seems overstated. The X-3 and XB-1 both have long noses, and the similarities end there. The wing shapes are completely different, the engine intakes are configured differently, the tail is completely different etc. In terms of similarities, it looks more like an X-59 to me: https://www.nasa.gov/aeroresearch/nasa-marks-continued-progress-on-x-59 https://www.nasa.gov/aeroresearch/nasa-marks-continued-progr...

ChuckMcM 6y ago
Lots of differences with the x-59, no wing canards, one engine on the x-59 vs 3 on the XB-1, the XB-1 seems much shorter. On the plus side the X-59 was developed by Lockheed and one of their advisors, Dr. Johnson was a CTO at Lockheed so there could be some cross pollination there. That said, its kind of picking nits. If everything's a remix[1] is true, that is even MORE true in aviation. [1] https://www.youtube.com/watch?v=nJPERZDfyWc https://www.youtube.com/watch?v=nJPERZDfyWc
- nl 6y ago
  > Lots of differences with the x-59, no wing canards, one engine on the x-59 vs 3 on the XB-1, the XB-1 seems much shorter. Um yeah of course? My point was the the long nose + wing shape (which defines much of the aerodynamics) is much more similar than the X-3 where the wing shape is completely different. See pics here: https://www.nasa.gov/centers/armstrong/news/FactSheets/FS-077-DFRC.html https://www.nasa.gov/centers/armstrong/news/FactSheets/FS-07... (Also hopefully the XB-1 is much better than the X-3 which was not a great plane!)