Revise with instant feedback: the moment you pick an answer you see whether it was right, with the explanation where available. Untimed — ideal before you sit a mock exam. Questions you miss keep coming back until you know them.
Exam-day conditions: no feedback until you submit, each module scored separately like the real test, with a full question-by-question review at the end.
The real exam is passed module by module: Rules of the Road requires 90%, most other modules 70%. Chart-plotting modules are taken on paper and not included.
The free sample gives you 20 to 30 questions per module. The full bank contains every available official question, with written explanations on the popular small-vessel credentials, one-off $29, lifetime access on up to 3 devices, all credentials included.
You must pass each module separately. Most modules require 70% to pass.
The exam covers 3 modules: Motor Plants, Engineering Safety & Environmental Protection, General Subjects.
This page includes free sample questions drawn from the official USCG sample examinations, with a full bank of around 175 questions across all modules available with lifetime access.
Every question comes from the U.S. Coast Guard National Maritime Center's published sample examinations, which are U.S. government works in the public domain. Wheelhouse Prep is not affiliated with or endorsed by the U.S. Coast Guard.
No. The free practice tests work in your browser with no signup. Your score history is saved on your own device.
A selection of free questions from the official USCG sample examinations. Use the interactive modules above for timed, scored drills.
With no environmental forces acting on the vessel, the center of gravity of an inclined vessel is vertically aligned with the __________.
When new piping sections have been fabricated for installation in a hydraulic system, prior to installation the piping should be __________.
Leadership style sometimes must change with the readiness level of the employees. Which of the following employee readiness level scenarios would be best suited for adopting a delegating leadership style?
Which of the following shipboard groups would be an example of an informal group?
Vessel special surveys are conducted how often in the life of a vessel?
There are many tasks to carry out prior to and during bunkering. What is the best way to insure no task is missed?
What type of maintenance system would be associated with accomplishing maintenance after a machinery breakdown?
As a management level engineering officer, you are apt to be the primary investigator investigating the root cause of the failure of a piece of machinery. Besides collecting and preserving the physical evidence of the failure and interviewing key personnel, which of the following supplemental information should be considered? I) Onboard operating and maintenance procedures II) Historical operating and maintenance records III) Technical manuals and specifications IV) Personnel training records
In general, the thermal bulb for a thermal expansion valve used in a reciprocating air conditioning system is usually charged with what substance?
A room humidistat initiates the lowering of the humidity of the conditioned supply air to a space, while the actual process is accomplished by what means?
When analyzing indicator card diagrams you are calculating the work output from the cylinder by obtaining the area within the curve of what type of diagram?
Worn diesel engine intake valve guides can result in __________.
One experiences evidence of high temperature corrosion on diesel engine combustion space components. This is exhibited by 'wire drawing' marks on exhaust valves/seats or metal reduction on cylinder heads. What causes this degradation of components?
In an auxiliary diesel engine, one reason for knurling the piston skirt is to __________.
On small diesel engines, a noticeable decrease in the time interval between the replacement of the lube filter cartridge indicates __________.
In a four-stroke cycle diesel engine, badly worn intake valve guides can cause excessive __________.
Fuel combustion in a diesel engine cylinder should begin just before the piston reaches top dead center and should __________.
Heavy fuel oils generally have an upper average ash content of 0.1% by weight. Which of the following conditions could be expected if the ash content increases above this amount?
The amount of fuel delivered by a unit injector is controlled by the __________.
High firing pressures and a low exhaust temperature in a diesel engine may result from __________.
Wooden shoring, with a cross-sectional dimension of 4" X 4" should not be longer than __________.
The wooden plug fitted tightly in the vent of a damaged tank may prevent the tank from __________.
Progressive flooding in the engine room may be minimized by securing watertight boundaries and _________.
Paints and solvents used aboard a vessel should be __________.
A simple precaution to reduce the possibility of accidental fires in the paint locker, is to __________.
How would you ensure that your crew is prepared to combat a shipboard fire using ship's equipment?
The most common cooling agent used for fighting fires on tank vessels is __________.
Water applied as a "fog" can be more effective than water applied as a "solid stream", because __________.
Why is it essential to introduce CO2 from a fixed fire extinguishing system, into a large engine room, as quickly as possible?
By what means should motor controller contacts be routinely cleaned?