• Re-light Starship engines, achieve stable orbit (they deliberately cut the engines just a few meters per second shy of it on IFT-3, there’s no reason not to count it), and transfer propellant (one of IFT-3’s test routines during its almost-orbit was transferring propellant between internal tanks).

        •  Player2   ( @Player2@lemm.ee ) 
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          66 months ago

          Actually they did not succesfully relight the engines in space as planned, but they intentionally skipped the test due to vehicle conditions as opposed to it failing

            •  Player2   ( @Player2@lemm.ee ) 
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              46 months ago

              They attempted to relight the booster, but only 1 of the 13 engines they wanted on actually started (2 others almost started but immediately failed). Their hope was to demonstrate in-space relight of the second stage engines, which is obviously a crucial demonstration for HLS and eventually going to the moon, but they never went for it. So far they have never demonstrated Raptor start in a vacuum and microgravity, which is a significantly different challenge to firing on the ground or even during re-entry as was the case for the booster due to propellant slosh and ullage considerations. In fact, we have seen them struggle with these issues in the earlier Starship solo tests, where the engines upon relight would eat backfill helium and eventually switch over to an engine-rich cycle :D. I’m sure they will figure it out but in space Raptor relights are far from the ‘same’ as what they have already done.

      •  FaceDeer   ( @FaceDeer@fedia.io ) 
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        6 months ago

        There was a propellant transfer done during IFT-3’s flight between internal tanks, too.

        The list’s not as big as it seems, several items are very closely related (there’s three separate items for “design, build, and test a life support system” for example).