The aero-engine business is tough and getting tougher. The ever more exotic materials and manufacturing processes mean that only those with the deepest pockets can sustain. Safran has been struggling with its Silvercrest engine. The delay in the engine is pushing the Dassault 5X EIS to 2020.
The problems seem to have a significant impact, as the Silvercrest does not have the power to work on regional jets. Another engine maker that has been working through challenges is Rolls-Royce. Bloomberg has a good story on these two firms. It is interesting that Safran’s CEO made the first public statement about collaborating with Rolls-Royce on engines for regional jets.
Safran collaborates with Rolls-Royce on the Trent 500, 700, 800, Trent XWB and BR700, 710, 715, 725 and TP400 (A400M). Safran collaborates with GE on the CFM56 and LEAP. It also collaborates with Russia’s NPO Saturn on the PowerJet used on the SSJ.  In short, Safran has its fingers in many engine programs.
What is not clear is what exactly Safran offers Rolls-Royce that the latter already does not have access to?
One thing which Safran might offer Rolls-Royce which R-R doesn’t already have is creating highly advanced carbon-fiber structures for use in medium-size and large commercial-aircraft engines. Through its subsidiary Snecma, Safran is the world leader in the application of carbon-fiber technologies for major structures in commercial aero engines, such as fifth-generation, 3-D aerodynamic composite fan blades made by the woven (using huge, automated Jacquard looms!) resin transfer molding technique, and also advanced CFRP fan casings. (The CFM International LEAP engine is the prime case in point: no commercial-aircraft turbofan engine that small has ever had carbon-fiber composite fan blades, because up until Snecma developed the fifth-gen woven RTM technique, no fan blade of suitable size could be made which was stiff enough and offered adequate aerodynamic capability.) Rolls-Royce does not have CFRP technology to anything like the same extent as Snecma, hence the fact all its engines’ fan blades are made from titanium or other metals. While Snecma’s woven RTM technique for fan blades is patented and proprietary to the LEAP engine, perhaps Safran might be able to offer R-R a few clues on applications for carbon-fiber structures in commercial aero engines.