On Mon, 15 Feb 2016, David Weinshenker wrote:
It seems like the Hall thruster is a more practical design...
given that the Russians have apparently been using them (and willing
to license out the idea) for a fairly long time, the relatively slow
adoption for Western space projects seems a little surprising. Why is
something like the SNECMA PPS-5000 only just now coming onto the market
as a production item?