The Raptor engine is obviously a key component in making the BFR a viable space transport. Here is a report on the status of the Raptor development: SpaceX’s Raptor engine nears flight-readiness for BFR spaceship hop tests – Teslarati
Perhaps not a coincidence, SpaceX’s propulsion engineering lead Tom Mueller stated in May 2018 that flight-ready Raptors were already “in work”, with the implication being that the finalized Raptor design had been completed and that manufacturing work was beginning in earnest. Barring an unexpected shift in testing strategies, SpaceX will optimize and verify Raptor’s flight design over the course of several hundred seconds of static fire tests, eventually leading into the same practices used for Falcon 9.
An update on Pad 39A mods for launching crews on Falcon 9/Dragon: SpaceX finalizing Pad 39A upgrades for return to crew operations – NASASpaceFlight.com.
Both Boeing and SpaceX now say they have met the 1 in 270 loss of crew probability estimate that NASA has been demanding they meet for the Commercial Crew vehicles: Commercial crew providers believe they now meet NASA safety requirements – SpaceNews.com.
Kathy Lueders, NASA’s commercial crew program manager, didn’t confirm that the companies have, in fact, met those safety requirements. “We’re learning from a NASA perspective about how to understand the assessments that we’re getting from each of the contractors and how to apply it,” she said. “We at the NASA team are assessing the modeling that each of the providers has done.”
She cautioned, though, about using the loss-of-crew figure as the sole figure of merit of the safety of either vehicle. “I sometimes struggle when people say that the loss-of-crew number is the safety number,” she said. “I don’t believe that that’s true.”
The second time that a Falcon 9 Block 5 first stage will be reflown is planned for the upcoming launch of the Argentinian SAOCOM-1A satellite into a low polar orbit from Vandenberg AFB, which now has a landing pad for the return of the booster: SpaceX’s second Falcon 9 Block 5 booster reuse closes in as rocket refurb continues – Teslarati
According to a number of comments from satellite engineers involved in the launch, most of the month-long slip rested on rocket availability, meaning that SpaceX was having some sort of difficulty with Falcon 9 components. Given photos and official comments showing that SAOCOM-1A was encapsulated in its payload fairing more than 5 weeks before launch (August 30th) and that Falcon 9 Block 5 is a fairly new launch vehicle, especially in a flight-proven configuration, the most logical explanation is that SpaceX is simply being extra cautious and thorough with B1048’s post-flight analysis and refurbishment.
Scott Manley gives his views on the BFR lunar mission:
Tim Dodd, the Everyday Astronaut, talks about the design evolution of the BFR: