NVX: Naval Variable-geometry Experiment
If you look at the top view you'll notice that the nacelle pylons seem to have the ability to swing backward
like the the wings on a Grumman F-14 Tomcat. Well that is because they can
...But unlike "BS" version that the
Intrepid class has(that is, the ship doesn't need to fold them in order to initiate warp), the Sigma-class modulates
its pylons according to its speed...for instance: The ship at standard cruise and low warp the plons are closer
to a 90 degree angle...as the ship moves into higher warp, the pylons swing back and closer towards each
other. At the highest warp speeds and in crossing into the transwap threshold, the pylons are at full sweep
all the way back...the nacelles then lock together intergrating the warp field with the inertial dampeners.
Hope that helps