AW&ST and SpaceNews are reporting that SpaceX says their 2nd Stage Falcon 9 reignition problem was due to frozen ignitor fluid lines.
TEA freezes at 227K and TEB even colder than that, 180K.Has TEA/TEB ignition been used before on 2nd Stage? Seems most upper stages are hypergolic, or augmented spark type ignition.
Apparently it hasn't been used much on American launchers. Ed Kelleher
