Riserless subsea coiled tubing intervention automation

A method may include positioning a vessel supporting a coiled tubing string over a subsea wellhead disposed on a wellbore; relaying and landing a distal end of the coiled tubing string to the subsea wellhead using a first injector, wherein relaying the distal end of the coiled tubing string may include relating a second injector into a subsea environment to establish a subsea injector, and wherein the first injector is a surface injector disposed on the vessel. The method may further include connecting a coiled tubing module to a pressure control assembly disposed on a subsea wellhead and using either the first injector or the second injector as a principal injector to extend the coiled tubing string into the wellbore, wherein the principal injector is determined based at least in part on a wellbore pressure. The method may further include performing a wellbore operation with the coiled tubing string, wherein the wellbore operation does not utilize a riser.