Comment by roskelld
3 days ago
The speed of that take off, or lack of, was wild. I don't think I've ever seen a rocket build up its speed so slowly.
The methane blue looked spectacular.
3 days ago
The speed of that take off, or lack of, was wild. I don't think I've ever seen a rocket build up its speed so slowly.
The methane blue looked spectacular.
> I don't think I've ever seen a rocket build up its speed so slowly.
New-Glenn has a low thrust to weight ratio vs other rockets and lower engine chamber pressure than some other engines to put less stress on the rocket and engines for greater reusability.
But the obvious cost here is less mass to orbit. But I suspect it's a given that they'll tweak up the margins once they have more flights under their belt.
That is a trajectory optimized for payload mass, with a set amount of first stage thrust. It is quite typical, historically. It just looks extra slow since the New Glenn rocket is quite enormous relative to historic rockets.
An impressive first flight by any measure!
No, that's not true. Back of the envelope estimates for New Glenn's launch tonight give a thrust to weight ratio of 1.2.
For the Space Shuttle, t/w at launch was 1.5, the same is true for Falcon and Starship. Delta Heavy was around 1.3. Saturn V was 1.2. None of this has anything to do with optimizing the trajectory.
Historic rockets around 1.2, including Shuttle, check your numbers. Starship is not a "historic rocket". It and Falcon 9 fly a trajectory that is optimized for something else, not max payload for a set first stage thrust.
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If my KSP experience tells me something it needs more boosters
Yes, those seven blue spikes were pretty amazing.
Doesn't show the diamonds, but sure shows that blue glow.
https://xcancel.com/JerryPikePhoto/status/187979379253615860...
Here's a good view: https://youtu.be/KXysNxbGdCg?t=6935
Starships first flight felt similarly slow, watched in person.