Hyannis (YTB-817) was a United States Navy Natick-class large harbor tug named for Hyannis, Massachusetts.

The contract for Hyannis was awarded 9 August 1971.

Stricken from the Navy List 21 August 1997, Hyannis was transferred to the United States Fish and Wildlife Service at Midway Atoll and renamed Constant II.

[1] In 2006, she was sold and renamed Sea-Link Pusher.

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