danieldyer

5 ms·

1.
by danieldyer 10y ago
It's worth pointing out that Concorde didn't cruise using its afterburners; it only lit them briefly to punch through the transonic flight regime.
2.
by danieldyer 12y ago
She's certainly far less well known than many of her contemporaries, but Noether's theorem is an incredibly important tool in theoretical physics, and has been described as "certainly one of the most important mathematical th
3.
by danieldyer 12y ago
Don't forget Emmy Noether: http://en.wikipedia.org/wiki/Emmy_Noether "In the judgment of the most competent living mathematicians, Fräulein Noether was the most significant creative mathematical genius thus f
4.
by danieldyer 12y ago
The issue is that people confuse getting into space with getting into LEO. Virgin Galactic are not even close to getting into LEO – their plan is to fly a ballistic trajectory which takes them just above 100km before falling back to Earth.
5.
by danieldyer 12y ago
Yes, my Kurzweil K2000 ( http://en.wikipedia.org/wiki/Kurzweil_K2000 ) supports fully customisable temperaments – you can even tune it to the Bohlen-Pierce ( http://en.wikipedia.org/wiki/Bohlen%E2%80%
6.
by danieldyer 12y ago
> Regarding the Square-Cube law, I'm not sure it's that relevant here. It's pretty clear you could put two of those engines in a AMA sized model, so not exceeding 55 lbf. That'd give you a thrust-to-weight ratio of gr
7.
by danieldyer 12y ago
Roughly speaking, the drag is proportional to cross-sectional area, whereas engine thrust required is proportional to mass, which in turn is proportional to volume. So, you end up running into a square-cube law situation: http://
8.
by danieldyer 12y ago
Exactly. It's just a radio-controlled model aircraft, which have been around for a long time. Also, it's worth pointing out that it's not a model of a fighter jet, and that this video seems to be a repost of one that's b
9.
by danieldyer 12y ago
Only if it were rocket powered. The aerodynamics simply don't scale well enough for something that small to become supersonic using any currently available small turbine engine.
10.
by danieldyer 12y ago
> Sounds shockingly good, so I have to wonder if the compressor is basically an ablative heat shield and this is good for only a few runs. The compressor isn't the part of the engine which gets really hot here; that would be the tur