Actually, I think all of the jet engine manufacturers these days are using 3d printers for some of their parts? Although you usually find the press releases talking about this using the term "additive manufacturing" instead. See, e.g., this press release from 2018 about a notable jet engine manufacturer using 3d printing: https://www.geaerospace.com/news/articles/manufacturing/manu...

(Although note that these are not using plastic parts, to be clear.)

Loads of commercial aircraft and jet engine parts are manufactured using additive manufacturing, or ”3D printing”