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Update: It appears that they called the launch because of winds, though it also appears that the lower oxidizer temperatures have also reduced their weather margins.
In the heat of competition: For the second day in a row SpaceX has canceled a commercial launch of its Falcon 9 rocket because they were unable to get the oxygen in its tanks as cold as required.
The denser propellant gives the rocket added thrust, contributing to what SpaceX says is a 33 percent overall increase in its performance compared to the previous version.
But during countdowns Wednesday and Thursday, SpaceX reported trouble keeping the “deeply cryogenic” propellant cold enough. Although Thursday’s launch window lasted 96 minutes, it turned out SpaceX really only had one opportunity during that window. If any problem arose, SpaceX said the liquid oxygen would have to be drained and re-loaded, a process that would take too long.
This problem is troubling, suggesting that there might be a more fundamental issue here than they are saying. First, there was the significant delay since the last launch of this upgraded fueling system in December, implying that the data from that launch required some reworking. Now, they have scrubbed two launches in a row because they couldn’t get the oxygen cold enough to properly fuel the rocket. I also wonder if they need to reach a colder temperature in order to get enough fuel loaded to get the satellite to its proper orbit.
I generally trust SpaceX’s engineers to address a problem and fix it. Right now, however, they are under the gun. They need to get this working and begin launching rockets on a more reliable schedule. They have a lot of customers waiting in line.