In the past 100 years, there have been tens of thousands of different U.S. ship cancels. Some of them, like yours, do not have a specific ship's name; sometimes this was done for mission secrecy.
The first scan shows U.S. Fleet Flagship (Navy Day in bars); Naval Air Station; Submarine Division Ten (----, China in bars); and Submarine Division Seven (Pearl Harbor, T.H. in bars). These old cancels fade over the years and get hard to read, especially in low resolution images like ours.
My second scan shows cancels from the 1st and 3rd U.S. Navy ships designated the
U.S.S. Altair (see Wikipedia). Below the Altair's is a cancel that merely says "Scouting Force," a good example of high security.

