Ozan Bellik's Blog

I often bring up the idea that the role SLS & Orion perform in taking crew to lunar orbit could be performed by Falcon Heavy launching a modified lunar Dragon with a crew of four, and I'm often met with skepticism from certain quarters of spaceflight fandom. Recently I've gotten frustrated that instead of framing their objections in the form of "how would that work with consideration X", many of the skeptics come out of the gate with phrasings along the lines of "that wouldn't work because X", seemingly not even considering the possibility that I and others have already accounted for X, Y, Z, and a number of other factors before bringing this up. Tired of trying to convince people one at a time, I've decided to lay it out here. I won't hit all of the details I've considered, but hopefully enough to convince most people that this is actually feasible. To be clear, I think of this as an alternate history story or an idea for a secondary or ...

SLS is meant for Orion and Orion for SLS... ...or so the conventional wisdom goes, but Orion was actually designed for a different mission architecture that included the Altair lander and the greater launch capabilities of the Ares V rocket. In that architecture, Altair would have handled the insertion into lunar orbit, and Orion would have only been responsible for the return. I've written about this before in my post on single launch Apollo Redux architectures that could have been. When Altair and Ares V were cancelled with Constellation, Orion was left without a way to do a roundtrip to low lunar orbit, so for Artemis, NASA ended up settling for NRHO, which is closer to Earth in delta v terms. This enables Orion to get in and out of lunar orbit on its own, but makes it substantially harder to actually land on the Moon, increasing the total lander delta v requirement from around 4km/s to around 5.5km/s, as well as dramatically reducing the frequency of rendezvous opportunities a...