Some people here seem not to be aware that Red Dragon has been cancelled because it was designed for Earth reentry and didn't have enough drag to cope with the much thinner atmosphere of Mars.
Some people here seem not to be aware that Red Dragon has been cancelled because it was designed for Earth reentry and didn't have enough drag to cope with the much thinner atmosphere of Mars. All possible reentry corridors at Mars ended up with a very high terminal velocity, and the rocket fuel needed to make the terminal burn took up too much of the internal volume. Of course real space engineers could have told them this right at the start, but Saint Elon never listens to them.This decision by Musk got virtually no coverage on space news sites, so I'm not surprised that many SpaceX fans don't know about it. NewSpace seems to follow an inverse Gresham's Law: Good news drives bad news out of circulation.
NASA’s EDL systems analysis tools were employed to assess the feasibility of landing a largely unmodified Dragon2 capsule on Mars, ... demonstrating that propulsive landing approach initiated in supersonic conditions is possible, albeit not mass optimal.
The actual reasons for Red Dragon cancellation are related to it being better just to skip straight to BFR, in particular as the paper I quoted mentions in its conclusions, the specifics of supersonic retropropulsion at this point depend heavily on the details of the architecture, so Red Dragon would not have done much to inform BFR design.
Would I be correct in saying that NASA was more concerned about the legs-through-shield idea when it pertained to the Earth landings? Greater and longer thermal loads etc.