Greece Category A Theory common mistakes
Greece Category A Theory · Understand the traps and how to avoid them.
When asked to plot a course to steer (CTS), the candidate reads the course directly from the rhumb line drawn on the chart without applying variation, deviation, or leeway, and then writes that value as the answer.
Candidates memorize 'variation east, magnetic least' as a phrase but do not build the true-to-compass chain into a habit. Under time pressure they treat the plotted line as the final answer, forgetting that the chart is true-referenced while the compass and autopilot are magnetic and subject to deviation and leeway.
What to do instead
Use a fixed four-step worksheet on every CTS question: true course from the chart, apply variation to get magnetic, apply deviation from the deviation card to get compass, then adjust for leeway (add or subtract the leeway angle on the windward side). Write each step on the answer sheet so the examiner can see the chain, and check the result against the reciprocal when returning.
In collision-regulation scenarios, the candidate answers from memory of the rule text but fails to state the give-way vessel's required action sequence (early and substantial action, then monitor, then take avoiding action if needed) and misidentifies which vessel is stand-on in crossing, overtaking, or narrow-channel cases.
The COLREG rules are learned as isolated sentences, not as a decision tree. Candidates confuse 'vessel on the right' with the actual rule (the vessel with the other on her own starboard side gives way), and they forget that a stand-on vessel must also act when collision cannot be avoided by the give-way vessel alone.
What to do instead
Draw the four geometry sketches (head-on, crossing, overtaking, narrow channel) and, for each, write the give-way vessel, the stand-on vessel, the required action, and the sound signal. Rehearse aloud: 'I am the give-way vessel, so I take early and substantial action to keep well clear, and I monitor.' Then state the stand-on vessel's duty to hold course and speed and to take action only when the give-way vessel is not taking appropriate action.
When interpreting a synoptic chart or a local weather forecast, the candidate answers with a generic 'bad weather is coming' instead of naming the pressure system, its direction of movement, the expected wind shift, and the sea state consequence for the planned passage.
Weather is studied as vocabulary (depression, anticyclone, cold front) rather than as a sequence of observable changes. Candidates do not link isobar spacing to wind strength or the passage of a front to a wind veer and a temperature drop, so they cannot turn a chart into a routing decision.
What to do instead
Practise a three-line briefing for every chart: (1) system type, centre pressure and direction of movement; (2) wind direction and force now and after the front passes, with the expected veer or backing; (3) sea state and visibility, and the go/no-go or shelter decision. State the isobar spacing explicitly when giving wind force, and name the wind shift in degrees.
In mooring and anchoring questions, the candidate lists the equipment (anchor, chain, warp, fenders) but cannot describe the sequence of manoeuvres, the scope to veer, the use of a second anchor, or how to spring off a quay against an onshore wind.
Seamanship is learned from checklists rather than from the physics of the manoeuvre. Candidates do not connect wind and current direction to the order of line handling, and they confuse chain scope (ratio of length to depth) with the amount of cable actually needed in shallow water.
What to do instead
For each scenario, write the wind and current vector first, then the order of operations as numbered steps: approach angle, which line goes first, engine and rudder use, and the abort point. For anchoring, state scope as a multiple of depth (for example 4:1 for chain in moderate conditions) and the veering procedure. Rehearse the spring-off sequence: single up, forward spring on, rudder and engine against the spring, then let go.
On legal and skipper-responsibility questions, the candidate gives a general statement such as 'the skipper is responsible for safety' without naming the specific obligation, the document, or the authority (flag state, port state, coastal state) that applies.
The legal domain is treated as common sense rather than as a set of instruments. Candidates do not distinguish among SOLAS, MARPOL, COLREG, the load line Convention and national implementing law, and they do not know which authority can board or detain a small craft.
What to do instead
Build a one-page matrix: instrument, what it covers, who enforces it, and the skipper's concrete duty (for example passage planning, watchkeeping, pollution reporting, and notification of a marine casualty). For each practice question, name the instrument and the enforcing authority in the answer, and state the action the skipper must take and to whom.
In firefighting questions, the candidate names the extinguisher type but cannot state the fire class, the correct agent, the technique (aim at the base, sweep), the boundary for fighting versus abandoning, or the danger of re-ignition and of using water on fuel or electrical fires.
The fire triangle and extinguisher colour codes are memorized, but the decision logic of containment, boundary cooling, and evacuation is not. Candidates also forget that a fire in an enclosed space may be starved of oxygen and flare when a hatch is opened.
What to do instead
For each fire class (A, B, C, electrical, cooking oil), write the agent, the technique, and the abandon criterion. Practise the order: raise the alarm, locate and isolate, attack at the base with the wind behind you, keep an escape route, and cool boundaries. State explicitly that you do not open an enclosed space without cooling and a charged hose ready, and that you use the fixed system and shore assistance for a major engine-room fire.
In man-overboard and distress scenarios, the candidate describes the recovery but omits the immediate actions in the correct order, such as pressing MOB on the GPS, throwing a dan buoy, posting a lookout, turning with the correct method for the sea state, and making the Mayday call with the required content.
The drill is remembered as a list of items rather than as a timed sequence. Candidates do not rehearse the first thirty seconds, and they mix up the Williamson turn with the quick stop, or forget that the propellor must be stopped before anyone enters the water.
What to do instead
Write and time the first thirty seconds: MOB button, throw float, shout and point, helm over, engine neutral, Mayday with position, nature, and number of persons. Then state the turn method and why (Williamson for a person lost overboard at night or in poor visibility; quick stop for an immediately visible person). Rehearse with a stopwatch and a crew briefing card.
On engine and electrical questions, the candidate gives a symptom-level answer ('the engine won't start, so check the battery') instead of a systematic fault tree: fuel, air, compression, ignition or injection timing, and electrical supply, with the specific test for each.
Maintenance is learned as a list of parts, not as a diagnostic sequence. Candidates do not separate a fuel starvation fault from an air lock, a blocked filter, or a failed lift pump, and they do not know the voltage and specific-gravity checks for a battery or the difference between a charging fault and a starting fault.
What to do instead
Use a four-branch fault tree for a non-starting diesel: fuel (tank, filter, air lock, lift pump), air (blocked intake, turbo), compression (valves, head gasket), and electrical (battery voltage, terminals, starter solenoid, stop solenoid). For each branch, name the quick test and the expected reading. For electrical faults, state the open-circuit voltage, the charged-specific-gravity range, and how to distinguish a discharged battery from a failed alternator.
In chartwork and passage planning, the candidate plots a route without checking for charted hazards, traffic separation schemes, or the under-keel clearance and safe-water depth for the planned state of tide, and does not mark a safe track with wheel-over points or an abort option.
Plotting is treated as joining two points with a line. Candidates do not build the habit of scanning the whole track for dangers, and they forget that charted depths are referenced to chart datum, so the actual depth depends on the height of tide and the vessel's draft.
What to do instead
Adopt a fixed passage-plan checklist: hazards within a set distance of the track, TSS and traffic lanes, safe-water depth (charted depth plus height of tide minus draft, with a minimum margin), wheel-over points, and at least one abort or shelter option. Mark each waypoint with a circle and the planned speed and ETA, and state the under-keel margin explicitly in the answer.
When answering questions about stability and loading, the candidate states that the vessel is 'stable' without distinguishing initial stability (GM), the righting-lever curve, free-surface effect from partly filled tanks, and the danger of a stiff or tender vessel.
Stability is learned as a single word rather than as a set of measures. Candidates do not connect the position of the centre of gravity to the metacentre, and they underestimate the loss of stability caused by free surface in a partly filled tank or by weight added high up.
What to do instead
For each loading scenario, draw the G and M positions and state the GM, then describe the consequence: a small GM gives a tender vessel with a long roll, a large GM gives a stiff vessel with a rapid snap roll. State that free surface raises the effective G and reduces GM, and that the fix is to press up or empty tanks, not to add weight high up. Use the righting-lever curve to show the range of positive stability.