Last fall’s engine failure indicated a potential problem with the Merlin 1C engine design or procedures, but validated the designed ability of the vehicle to complete its mission with engine out. Unfortunately, that particular lesson had a short shelf life — Friday’s flight was the last for that version. All Falcon 9s going forward will be larger, with more powerful and simple (and presumably reliable) Merlin 1D engines with more performance. But the general knowledge will be carried forward into that vehicle, and it will be a good gradual evolution from the early successful version.
This latest glitch not only pointed out a potential issue for the Dragon, but demonstrated once again (as had been seen in the rapid turnarounds on the pad after aborts on previous flights) the team’s ability to quickly diagnose and to make decisions to ensure ultimate mission success. If the current theory of the cause of the problem is correct, it may also result in a change in either design or processing procedures to ensure that propellant temperatures don’t get out of spec. Either way, the company has once again demonstrated the robustness of their designs and operations, building on the lessons learned from their many early failed launch attempts of the Falcon 1 which eventually resulted in a successful vehicle.
This will likely give NASA continued confidence going forward that they will ultimately, perhaps within two or three years, be able to safely deliver the agency’s astronauts to and from orbit and finally eliminate our dependence on the Russians.