I could find many papers about the use of carbon fiber coated with CNT and many papers about CNT used as multifunctional fillers dispersed in the matrix but not with fiber reinforce.
May I also ask you if there is any particular product (perhaps a specific boat or airplane) that uses this particular type of fibers currently on the market?
Please also check this one: Multi-component nanocomposites of epoxy/silsesquioxane reinforced with carbon fibers and carbon nanotubes processed by resin transfer molding: Polymer-Plastics Technology and Materials: Vol 59, No 5 (tandfonline.com)
I published several papers about carbon fiber-reinforced composites (CFRP) where CNTs are added to the matrix to form multi-scale reinforced composites. Please check:
DOI: 10.1016/j.compstruct.2019.02.020, High performance functional composites by in-situ orientation of carbon nanofillers
DOI: 10.3390/nano8110912, Acid free oxidation and simple dispersion method of MWCNT for high-performance CFRP
DOI: 10.4028/www.scientific.net/KEM.742.31, Processing of Carbon Nanotubes and Carbon Nanofibers towards High Performance Carbon Fiber Reinforced Polymers