It is a famous 3D printing story where GE produced titanium fuel injection nozzles for a turbofan engine. 3D printing allowed it to be constructed 25 percent lighter and in a single piece instead of an assembly of 18 parts, making a 5 times more durable part. It is also used in some automotive applications to make for lightweight pieces. You will need to make a detailed analysis in order to see whether the increased manufacturing cost weighs up against the benefits of the part geometry, durability and reduced labor time. I definitely see a big future in aeroplane manufacture for 3D printing. Airbus does a lot of research into this: http://www.airbusgroup.com/int/en/story-overview/Pioneering-bionic-3D-printing.html