/sci/ - Science & Math

>>12778575
I was really pleased to see Casey tear into hydrogen booster stages as an entire concept in that "cancel SLS" article

>Let’s talk about hydrogen. Shuttle designers gravitated towards hydrogen as a fuel because its specific impulse is substantially higher than other fuels...
>Modern consensus is that once the cost, complexity, and additional mass required to deal with hydrogen is factored in, its performance is not favorable compared to other more conventional fuels, such as RP-1 or methane
>hydrogen is a hard cryogen, requiring extra insulation and mass. It easily leaks through sub micron valves, seeps through metals causing embrittlement, and is so cold that it restricts choices on materials
>...ISP isn’t everything. At launch, a rocket... needs high thrust to punch through the atmosphere. Here hydrogen is next to useless

>>12485646
yes. This is why ULA has to use more insulation on their centaur 2nd stages on longer GTO missions. Because if they didn't they'd literally lose too much fuel to complete the mission.

They have proposed clever ways to circumvent this, though. Their ACES system was supposed to use the boil-off to power an active cooling system. A neat approach, but as of now it only exists on paper.

>>12485666
Larger but has almost 2.5x less thrust. Musk is right; hydrogen is hell.

>>12311265

>>12293526
it worked about as well as you'd expect.

And for fun, price:
F9: 62M
FH: $90M
DIVH: $350M
No wonder oldspace is seething so hard. SpaceX is seriously cutting into their ability to make hundreds of millions off of their shitty rockets.

>>12287137
yep

>>12265882
it solidified once and for all that hydrogen 1st stages are a complete joke

>>12255845

>>12156308
>>12156312
>worlds richest man
>can't even launch a sounding rocket on schedule

>>12087127
>>12087153

>>12019749

>>12012964
>>12012952

>>11993907

>>11986294
>hydrologs side boosters
Delta IV heavy does it

How can old space even compete?

>>11892855
i just threw a bottle cap at the wall and it now has more flights than sls and new glenn.

>>11854532

>>11843017
it's hypergolic tho

>>11834024
Hydrolox density is such a meme.