DDE (Designated Duty Engineer) Practice Test, 1,000-4,000 HP

The one-engineer ticket for tugs, towboats, ferries and supply boats up to 4,000 horsepower. Coast Guard exam code DDE04.

244 real questions from the Coast Guard National Maritime Center's public sample exams, free. Each module needs 70% to pass.

Passing score: Coast Guard pass marks module by module, and the retest rules

What's free: daily rounds, the Brig, the drills and the Pass Meter, for every license. Your first module test is free too. After that, the full Exam Room is $19, once. No subscription.

What's on the test

Picture questions link to the drawing in the Coast Guard's free sample PDF. A few that need reference tables are left out.

10 sample questions

1. Diesel engine closed, re-circulating cooling water systems are particularly prone to cavitation corrosion/erosion. Which of the listed cooling system/engine components has surfaces in contact with the coolant that are most susceptible to this type of corrosion and erosion?

   • A.Engine exhaust cooling water jackets
   • B.Wet-type cylinder liners
   • C.Cylinder cooling water jackets
   • D.Cylinder head cooling water passages
   Show answer

   B. Wet-type cylinder liners

   Q610, Assistant Engineer Limited: Motor Plants

2. Babbitt is a metal alloy commonly used for lining __________.

   • A.shim stock
   • B.valve seats
   • C.precision bearings
   • D.saltwater piping
   Show answer

   C. precision bearings

   Q806, Fireman / Watertender

3. When conducting a borescope inspection, you must be aware of all of the following factors EXCEPT which?

   • A.The internal reference points.
   • B.The limitations of your equipment.
   • C.The inspection areas and ports.
   • D.The engineer's experience.
   Show answer

   D. The engineer's experience.

   Q606, Chief Engineer Limited: Gas Turbine Plants

4. Which extinguishing agent is the best for use on electrical fires?

   • A.Water fog
   • B.CO2
   • C.Dry chemical
   • D.Foam
   Show answer

   B. CO2

   Q451, Deck General / Safety

5. In general, the thermal bulb for a thermal expansion valve used in a reciprocating air conditioning system is usually charged with what substance?

   • A.mercuric sulfate
   • B.bees wax
   • C.the same refrigerant as the system
   • D.distilled water
   Show answer

   C. the same refrigerant as the system

   Q801, Junior Engineer, Part II

6. If the water level as indicated by the gauge glass of an auxiliary boiler is in question, it should be blown down. Which of the following statements represents the proper procedure for performing a gauge glass blow down?

   • A.The gauge glass should be blown down twice; first with the upper cut-out valve open and then with the lower cut-out valve open.
   • B.The gauge glass should be blown down once with the lower cut-out valve open.
   • C.The gauge glass should be blown down twice; first with the lower cut-out valve open and then with the upper cut-out valve open.
   • D.The gauge glass should be blown down once with both the upper cut-out and lower cut-out valves open simultaneously.
   Show answer

   C. The gauge glass should be blown down twice; first with the lower cut-out valve open and then with the upper cut-out valve open.

   Q610, Assistant Engineer Limited: Motor Plants

7. By which of the listed methods may heat be transferred from one body to another?

   • A.Conduction
   • B.Convection
   • C.Radiation
   • D.All of the above
   Show answer

   D. All of the above

   Q808, Pump Technician

8. Which of the following is the main advantage of a split-axial compressor case?

   • A.Stronger construction
   • B.Cheaper to manufacture
   • C.Easier to repair and inspect
   • D.Simpler to disassemble
   Show answer

   C. Easier to repair and inspect

   Q606, Chief Engineer Limited: Gas Turbine Plants

9. The advantage of using a dry chemical fire extinguishing agent is __________.

   • A.its excellent cooling ability
   • B.permanent extinguishment regardless of the reignition sources
   • C.its good stability and non-toxicity
   • D.all of the above
   Show answer

   C. its good stability and non-toxicity

   Q801, Junior Engineer, Part II

10. What statement is true concerning the total resistance of a parallel circuit?

    • A.The total resistance is equal to the sum of the individual branch resistances.
    • B.The total resistance is smaller than the lowest branch resistance.
    • C.The total resistance is larger than the greatest branch resistance.
    • D.The total resistance is equal to one-half the sum of the individual branch resistances.
    Show answer

    B. The total resistance is smaller than the lowest branch resistance.

    Q802, Electrician

What the study guide does

• Short daily rounds of 10 questions, with a streak.
• Practice tests built like the real one, scored with the real pass marks (first one free, then $19 once for the full Exam Room).
• The Brig: questions you miss come back until you get them right twice.
• Pass Meter: your chance of passing every module if you sat it today, worked out from your own answers.