Shlazzargh Ars Praetorian
8y
536
I think that the fact that you can point to a specific Falcon 9 rocket and say "This rocket has flown more times than all of the Delta IV Heavy's combined" says quite a bit about how our view on rockets and reusability have changed. The D4H is an amazing rocket that does the job well -- a now it is even easier to see what a shame it was to just throw all that work in the ocean after one time. //

Wickwick
To be a bit more fair, the Delta IV flew 45 (?) times. With side cores on the Heavy variant, that’s a total of 77 total cores. For the pre-SpaceX industry, that was a respectable number. //

melgross Ars Tribunus Angusticlavius
21y
9,197
Subscriptor++
stdaro said:
the sad thing, to me, is the lack of vision from the venerable old space enterprises. They had the engineering skill and the resources to scale up space access like spaceX has, but were strip mined for profit by finance bros who just saw an opportunity to demand rent from the government for the accomplishments of their predecessors.

Had the D4H been developed and evolved over time, and especially if rocketdyne had made an attempt to scale up and reduce the cost of the rs-68, we could be seeing it competing with F9H and Atlas now, instead of being abandoned.

Boeing/ULA and rocketdyne had a 40 year head start on SpaceX, but somehow ended up with raptor being the better engine, and starship being the largest launcher to ever reach orbit.
It wasn’t that management stripped them. It was a different time, when NASA and other space agencies hated the very idea of independent companies competing with them. Even the Delta was really done in conjunction with the government. not until someone at NASA, a few years ago, I forget her name, convinced them to give a contract to SpaceX, did things change. //

normally butters Ars Praefectus
17y
4,935
Boeing designed the Decatur rocket factory to produce 50 Delta IV core stages per year. This was an audacious bet on the future of commercial launch demand. Soyuz/R-7 barely achieved those annual late rates at their Soviet-era peak. Now Delta IV is retired after fewer than 50 launches all-time, although over 50 cores were flown due to the triple-core Heavy configuration.

It would take another generation for Falcon 9 to meet and exceed the flight rates that Delta IV was envisioned to support. But when that finally happened in 2022, SpaceX did it with just 4 new F9 boosters. It's the much smaller upper stage that occupies most of the stage manufacturing floor space in Hawthorne.

Ultimately, I think Boeing was looking at the same market potential we see today: LEO comsats from the likes of Orbcomm, Globalstar, and Teledesic. But the business model for those companies collapsed across the board due to high costs and the dot-com bust. They needed launch costs lower than anybody could provide at the time, even ILS Proton, and frankly they probably had cost issues with the production of their satellites as well.

The tandem duo of F9 and Starlink cracked the chicken-and-egg problem, by using vertical integration to bootstrap the new market segment rather than anticipating others putting the remaining pieces in place. //

normally butters Ars Praefectus

I think it's important to understand that RS-68 was a prime example of the kind of vision you're describing. That's what happens when the venerable old space enterprises enthusiastically take on the challenge of developing a less expensive rocket engine. RS-68 was their vision of a highly-simplified replacement for the RS-25, sacrificing performance in pursuit of lower cost. The J-2X engine developed for the Ares rockets was over 70% heavier than than Apollo-era J-2 in pursuit of simpler manufacturing.

There was once a proposal for an RS-68R evolution with a regeneratively-cooled nozzle instead of ablative cooling. But regen isn't something that's easily bolted on to an existing engine, it would have been a dramatic redesign, and the redesign process would have been very expensive. It's difficult to pay Aerojet-Rocketdyne to make their engines cheaper without the amortized cost of the redesign exceeding the unit cost reduction. That's what happened with NASA's decision to fund RS-25E development. The amortized development costs actually made each engine more expensive than the older version.

Also note that when Delta IV was being conceived by McDonnell Douglas in the 1990s, post-Soviet Russia was offering phenomenal world-beating kerolox booster engines for extremely attractive prices, and that's what designs like Delta IV would be up against. Boeing was more interested in their stake in the commercial Sea Launch venture, based on the Russian/Ukrainian Zenit rocket, than their Air Force bid. It seemed foolish to invest in kerolox engine development when it would require billions of dollars and well over a decade to match what they could buy off the shelf for the aerospace equivalent of "dirt cheap."