HC-144 Ocean SentryHC 144 Ocean Sentry airplane model. The Ocean Sentry, HC 144A, is the first all new aircraft delivered to the Coast Guard as part of the Coast Guards progressive modernization and recapitalization of aging legacy assets. The EADS HC 144 Ocean Sentry is a medium range, twin engined turboprop aircraft used by the United States Coast Guard in the search and rescue and maritime patrol missions. Based on the Airbus Military CN 235, it was procured as a