Proxima J-Star has admitted that is has been contracted by the DDS to work on employing hybrid technology in a new version of the Pulsar's engine. The admission follows media speculation. Proxima J-Star are a major DDS partner who have done much of the development work on the Neptune/Meson and future Pluto/Gluon families of engines for the DDS. Up until now they have not been known to have done much work on employing Gluon technology in existing engine design (so-called hybrid technology) however.
It is thought the Pulsar class will receive an upgrade beyond the planned MULE3 by the end of the decade. Jane's DDS Monitor has reported a project called Pulsar 1000 which includes a new engine to push cruise speed beyond 1000c though the DDS have declined to comment so far.
