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tnorthcutt

For anyone curious about aerospike engines, Tim Dodd has a great in depth video on them: https://youtu.be/D4SaofKCYwo

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If you'd rather read Tim Dodd than watch his video, here's the text version: https://everydayastronaut.com/aerospikes/

Alternatively you can watch the video on mute with captions turned on, which is my favorite approach

To me, that's like the worst of both worlds. You have text, but you can't read it at your own chosen speed.

You can always pick a faster / slower playback speed in YT

And you get to keep the images, which are not there for the text-only version

YT maxes out at 2x, which is extremely slow

If you're on desktop: https://chrome.google.com/webstore/detail/youtube-playback-s...

Go beyond 2x!

Love this extension. I watch almost everything at 2.5x now.

No need for an extension -- I'm paranoid and rather not install anything unless absolutely necessary -- when a simple one-liner bookmarklet will do:

  javascript:(() => { document.querySelector("video").playbackRate = 16; })();

I make a few copies for different rates (1.75x, 2.5x, etc.); this is the one I use to fast-forward ads whenever my ad-blocker fails.

But... why? Having to read the captions prevents you from watching the video.

People have been watching subtitled movies for decades.

Indeed, people outside of USA (and France, Germany, and a few others that dub everything) have lived with this their entire lives. Even today my wife and I watch with subtitles as it's not always easy to hear all of the dialogue over the other noises in movies/shows.

You can also play the YouTube video with your eyes closed to get the audiobook version.

From what little i've seen of this guy; he appears to have no actual technical understand or depth to anything he reports on and basically just echos pop science and press releases. Scott Manley, Curious Mark and Periscope archival footage comes to mind for high quality content to learn about rocketry and related technology.

I like him a lot, but recently in his tweet he didn't even know how pressure varies with area in a nozzle. I do think he should learn a bit more.

He’s be the first one to tell you that he’s an amateur who is always trying to learn more.

He actually interviews people who know what they are talking about and does the research. He has good contacts in the industry, better then most people. The video actually contains lots of information you can't find anywhere else. He spends a lot of time validating his videos himself with industry expert and then has a huge patreon community that goes threw everything and tries to find errors.

He is an educator he doesn't have to be able to design his own engine to make good educational videos.

And Scott Manley is also not an engineer and Scott Manley actually used Tims graphics in his own videos.

Right now he is working on a 1h 30min video on Russian engines that is more detailed then anything out-there and he spend 2 years researching it.

I think that’s over-stating it. His content is deliberately designed to be accessible to everyday people, so it necessarily needs to be limited in depth and detail. Having heard him on podcasts and other settings, his knowledge seems plenty in depth to me (an amateur enthusiast who wants lots of detail) for that role. He’s not an engineer, and that’s fine.

In Tim's interview with Elon Musk, Elon mentioned[1] low combustion efficiency as one of the major disadvantages of aerospike engines compared to the more traditional bell nozzles used on Raptor.

I wonder if Pangea has done anything in an attempt to solve that problem.

[1]: https://youtu.be/cIQ36Kt7UVg?t=408

>> Elon mentioned low combustion efficiency as one of the major disadvantages of aerospike engines

If you haven't seen the SpaceX presentation on their combustion CFD software, it's a must see. They have state of the art simulation capability in this area - better than any commercial offerings.

That was 6 years ago, hard to say what remained of that ambitious goal. Also, these guys aren’t with SpaceX anymore.

Raptor has since exceeded its target performance, maybe they ran out of frontiers to explore?

I don’t understand your comment. What does Raptor have to do with CFD method developments? What is the frontier? What does it mean to run out of frontiers? Shouldn’t there be more resources rather than fewer?

I don't think they stopped development of that tech just because some people left.

They clearly invested massively in engine development from then on. I don't think they simply stopped.

And Raptor has turned into the best engine ever since then. Likely the used lots of simulation in development.

Everyone keeps posting this, but there's no update on that video.

They seem kinda busy over there, maybe they have higher priorities?

I have no idea why people recommend this guy. Such bad 40 seconds wiki article reading with a annoying way of talking.

A personality driven channel versus engineering

If he just stepped back and kept his personality out of it would be much more tolerable.

His target audience is not the highly technical, but the public at large - including children. He's a space ambassador in that he wants to get the current and upcoming generation excited and learning about space.

With that said, he has been able to get in-situ interviews with rocket company CEOs including his amazing 2 hour almost single take video tour with Elon Musk [0] where I was able see Elon comfortable in speaking much more deeply, candidly, and enjoyably than with any interviewer/reporter prior. Tim Dodd is no professional engineer but he really knows his stuff. His personality helps bridge the gap between the highly technical and the layman.

[0] https://youtu.be/t705r8ICkRw

Well put.

Personally I love that Tim's personality shines through in his videos. His enthusiasm is infectious and just plain nice to see, IMO.

Why. The personality removes so much information density.

Well, after spending eight hours working demanding jobs, be it physical or mentally, everyday people usually like to spend their free time with something a little more relaxing, and for most people that isn't reading documentation or reading highky technical engineering papers but rather watching a highly enthusiastic guy try and share his joy of rocket science.

Content can be also be entertaining to watch. Not everyone wants to superoptimize their time.

Then just read a university text-book and don't look for that in a educational video.

That’s a good point. I’m not an engineer yet I prefer there be more description and less personality shining through; but you make a good point about target audience. And as you say he prepares for the material and does well to understand the experts.

Well sure, but there are moments where Elon just flat out ignores him, so idk.

He actually researches history, has contacts with many important people in areospace and actually managed to all the CEO from all the companies that had reached Orbit about the topic, Musk, Bruno, Beck. Since that video he also talked to it with the CEO of Firefly (that used to develop a spike and was propulsion engineer at SpaceX).

If you think you are to good to hear from those people then maybe you should get of your high horse.

Just because its not designed for only engineers doesn't mean it shouldn't be recommended. Find me a better video or article about areospikes.

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