I'm not sure about engineering trades, but the Navy does have Communications Technicians (CT's), who can either join direct entry, or transfer sideways entry. Their promotion is automatic up to CPOCT, although not as automatic as it once was.
The last Artificers have joined the RN and pass out of the training establishments soon - those that have completed the apprentiship. All those joining from September will be known as Engineering Technicians (ETs) and will put either (ME), (WE) or (AE) after ET. Most of those serving (and those on course) will migrate to the new titles over the next year or in April 2007 for the MEs. A trial is being run in HMS NORTUMBERLAND. The formal apprentiship will be gone with those more academically capable being put on a longer course at about the Leading Hand level. The delivery of core skills that were done by the CPO Artificer will be done by the POETs. (The cynic in me says that this is another money saving gag). Those still serving who are by registration with the Engineering Council Incorporated Engineers will still be called Engineering Technicians by the RN. This is seen by many as a step down the recognitian scale. Artificers have been in the Royal Navy for hundreds of years and April 2007 marks the end of an era in Naval history.