I basically opened that Hotstart Mission for the Marianas for F-18C into the mission editor and changed the ship to Truman. I also checked LSO and Airboss, out of curiosity more than anything else. When I then tried to fly as a pilot, the "press the space bar to end pause" did not work.
I assume this is another one of those "known bugs"?
After I removed those checkmarks in the Editor, it worked fine.