L-1011 Engine
I am not sure about the length of the engine being the reason for the RB 211 engine being the only engine offered by Lockheed. I would have thought that, despite some early teething problems and late availability with the -22B, the RR was the best option for commercial and, subsequently operational, reasons. As well, I believe the USA Federal government provided financial support for RR Aeroengine division who were bankrupted by the development of the engine. Don't quote me though, just my thoughts on the issue. 411a may have more info. BTW mate, the centre engine of the DC-10 and MD-11 is not mounted in the rudder, but in the vertical stabiliser (Fin). In typical LOckheed fashion the L-1011 was somewhat "over-engineered", but was probably one of the nicest aircraft cockpit environments in which to work ever offered.