This is a screenshot of an effect that I am reproducing in my next task for [Daetrexx engine glows]. The Ogre version will be slightly different, different color, length based on speed, and more concentrated. That is… if I can pull spare time out of my hat.
The original effect can be achieved by adding a solar flare, using an animated texture for the exhaust, adding some volume with funnel textures (4 axis aligned billboards), and a face texture (as seen from the back). Now the face texture actually needs to be just behind the solar flare, otherwise it would appear as an out of place artifact.
The effect in action: