While actually under construction for quite some time, a name hadn’t been chosen yet! Endeavor will be a “Horizon Class” DSV, that is, almost identical to DSV-3 Horizon!
Endeavor’s name is from the Crew Shuttle Endeavor, which has been out of service for some time now!
“I miss flying those Crew Shuttles… when are they going to be cleared for flights again!?”
Unfortunately, it may be quite some time for them to get cleared again – the basic design of a spaceplane makes it difficult to create a design with multiple abort options throughout the flight. In fact, there are no launch aborts available right off the launch pad!
“The engineers are working on it! No promises though!”