Completion of this class, with a total of three years of creditable sea service, will prepare the mariner to serve as Engineer on vessels of up to 500 gross tons on ocean routes.  The mariner will no longer be restricted to service in "near coastal" waters and can travel beyond 200 miles from the nearest land.  It is required that the mariner take a complete "DDE any horsepower" exam regardless of whether he has taken an earlier DDE exam. Never­theless, it is possible to obtain a "DDE any horse­power" license directly by presenting three years of total documented sea service, most of which is in the engineering department, and by taking the appropriate exam.

This 4 or 8 week USCG approved course provides unlimited designated duty engineer candidates practical knowledge and training in all phases of off-shore supply and towing vessel engine room operations in preparation for licensing.  All aspects of steam and motor test
preparation are provided.  Topics covered include engine room safety, tools and supplies, piping system hardware, miscellaneous piping systems, pollution abatement equipment, vessel habitability and fluid power systems, electrical equipment and maintenance, and electricity generating and diesel propulsion plants. Emphasis is placed on theory of operation, monitoring procedures and conducting of machinery space rounds, inspections and record-keeping, and engine room operating, troubleshooting, maintenance and repair procedures. Applicant who successfully completes this 160 (or 320) hour DDE Unlimited HP course will receive 45 days of sea service credit that can be applied to the service requirements of 46 CFR 10.524 (h) (2) and (3) for a license as a Designated Duty Engineer Unlimited HP.

Designated Duty Engineer: a qualified engineer, who may be the sole engineer on vessels with a periodically unattended engine room.