1 July According to the Maritime Administration, there are 553 vessels of 1,000 tons or over in the active oceangoing merchant fleet as of this date. There is no change in active vessels and an increase of 1 inactive vessel as compared to 1 June 1977. The number of vessels in the privately owned fleet is 577. Of these, 532 are active. The total U.S.-flag merchant fleet increased from 1 June 1977 by 1 to 846.
9 July The missile-armed hydrofoil USS Pegasus (phm-1) was commissioned at Seattle, Washington.
The Spruance class destroyer USS Peterson (dd-969) was commissioned at Pascagoula, Mississippi.
13 July Secretary of the Navy Claytor announced the reappointment of Admiral Hyman G. Rickover, usn (Ret), as Head of the Navy Nuclear Propulsion Program for additional two years beyond his present appointment, which extends his appointment until January 1980.
14 July An unarmed U.S. Army ch-47 Chinook helicopter strayed into North Korea and was shot down, with three crewmen killed and one captured by the North Koreans.