3 ms·

It clearly wasn't all that minor, the story is always told as if it'd have been fine if Congress just allowed the alternate tanks, but it's worth considering th

It clearly wasn't all that minor, the story is always told as if it'd have been fine if Congress just allowed the alternate tanks, but it's worth considering that the work with the aerospikes was still so incomplete and risky, that even now, no serious company will risk attempting them, with the leaders by far in rocket engine tech, SpaceX, opting for the ridiculous complexity of Raptor over aerospikes. Then besides all that, VentureStar was never going to be able to overcome the issue of rocket SSTOs just not being efficient in Earth gravity. It's just way more efficient and not much more risky to have two stages.

cubefox 3y ago
Of course Starship is a better design now, but the VentureStar had a shot a full reusability long before it, and all that with a small fraction of the Cost-plus budget of the Space Shuttle. The Dream Chaser certainly doesn't achieve full reusability, and it is doubtful whether it is even overall better than Dragon on Starliner.
- dotnet00 3y ago
  The point is that it didn't have an efficient (and therefore cost effective) shot at full reusability. That's always been the key issue. There were plenty of designs for partially or fully reusable spacecraft, none were done in a way to be cost effective. The space shuttle being the poster child for this sort of thing, so expensive to refurbish that being reusable was almost meaningless. As an SSTO, VentureStar's payload would've been very limited compared to a two stage rocket of the same fuel capacity. The X-33 prototype that was being built was a scaled down suborbital version which doesn't even list a payload amount.
  - cubefox 3y ago
    The VentureStar was explicitly designed for low refurbishmemt demands given the failures of the Space Shuttle. The latter was developed by NASA using contractors, which pretty much always results in extremely high costs, e.g. recently with the cancelled NASA space suits or SLS. Even with Hydrogen, I think the full reusability of the VentureStar could have outweighed its high fuel cost, compared to other rockets at the time. They estimated 20 tons to LEO, which would have been more than e.g. Atlas, which wasn't even designed to fly humans, and would have required a capsule that reduces effective payload.

cubefox 3y ago

Of course Starship is a better design now, but the VentureStar had a shot a full reusability long before it, and all that with a small fraction of the Cost-plus budget of the Space Shuttle. The Dream Chaser certainly doesn't achieve full reusability, and it is doubtful whether it is even overall better than Dragon on Starliner.

dotnet00 3y ago
The point is that it didn't have an efficient (and therefore cost effective) shot at full reusability. That's always been the key issue. There were plenty of designs for partially or fully reusable spacecraft, none were done in a way to be cost effective. The space shuttle being the poster child for this sort of thing, so expensive to refurbish that being reusable was almost meaningless. As an SSTO, VentureStar's payload would've been very limited compared to a two stage rocket of the same fuel capacity. The X-33 prototype that was being built was a scaled down suborbital version which doesn't even list a payload amount.
- cubefox 3y ago
  The VentureStar was explicitly designed for low refurbishmemt demands given the failures of the Space Shuttle. The latter was developed by NASA using contractors, which pretty much always results in extremely high costs, e.g. recently with the cancelled NASA space suits or SLS. Even with Hydrogen, I think the full reusability of the VentureStar could have outweighed its high fuel cost, compared to other rockets at the time. They estimated 20 tons to LEO, which would have been more than e.g. Atlas, which wasn't even designed to fly humans, and would have required a capsule that reduces effective payload.