3D-printed rocket remains grounded after more launch aborts

A rocket made almost completely of 3D-printed parts remains grounded after back-to-back launch aborts. Relativity Space's rocket came within a half-second of blasting off Saturday on its debut flight from Cape Canaveral, Florida. The engines ignited, but abruptly shut down, leaving the rocket standing on its pad. Launch controllers reset the countdown clocks and tried again. But once more, on-board flight computers halted the countdown, this time with 45 seconds remaining. Wednesday's launch attempt got down to the final minute.