Free boating theory questions and short answers
Search-friendly answers for Day Skipper theory, Marine Radio SRC, VHF procedure, buoyage, lights, tides, CEVNI and practical revision. Each page has one question, a short answer, a mini quiz and a link to revise the full topic.
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Buoyage
What colour is a port-hand mark in IALA Region A?
A port-hand mark is red in IALA Region A.
Marine Radio SRC
What is the difference between Mayday and Pan-Pan?
Mayday is distress with grave and imminent danger; Pan-Pan is urgency without immediate grave danger.
Marine Radio SRC
What is the difference between VHF Channel 16 and Channel 70?
Channel 16 is for voice distress, urgency, safety and calling; Channel 70 is for DSC signalling only, with no voice traffic.
Lights and shapes
What is an isophase light?
An isophase light has equal periods of light and darkness.
Tides
How do you calculate tidal height for a simple depth check?
Add the height of tide to the charted depth, then compare the result with draught plus a safety margin.
Signal flags
What does a yellow flag mean on a boat?
A plain yellow Quebec flag means the vessel is healthy and requests free pratique.
Position coordinates
For practical Mercator chartwork, one minute on the nearby latitude scale represents what distance?
One nautical mile
Terms
On a vessel's sidelights, what colour marks the starboard side?
Green
Terms
What is the 'draught' of a vessel?
The depth of the hull below the waterline
Terms
What does a halyard do?
Hoists a sail up the mast
Terms
What is 'leeward' and how is it pronounced?
Away from the wind — 'loo-ard'
Terms
What is 'freeboard'?
The height of the deck above the waterline
Terms
What is the 'kicking strap' (vang) used for?
Holding the boom down to control mainsail shape
Terms
What does 'abeam' mean?
At right angles to the vessel's centreline
Terms
What is the difference between a 'shroud' and a 'stay'?
Shrouds support the mast from the sides; stays support it fore and aft
Terms
What does amidships mean?
The middle area of the vessel
Coastal planning
What is a lee shore and why is it considered dangerous?
A shore towards which the wind blows — dangerous because wind and waves can reduce sea room and drive the vessel towards danger
Direction and movement
What is the difference between 'course' and 'track'?
Course is a specified intended or steered direction; track is the actual path made over the ground
Coastal planning
In navigation, what is 'fetch'?
The distance over water for which wind blows in a broadly consistent direction—one factor in wave development
Direction and movement
What does 'making good' a course mean?
Actually achieving the desired track over the ground; planned corrections may help, but the result is observed
Coastal planning
What is a transit in navigation?
Two identified charted objects observed in line, giving one line of position without a compass
COLREG terminology
What does it mean when a vessel is described as 'making way through the water'?
The vessel is moving relative to the surrounding water
Direction and movement
What is the difference between 'heading' and 'bearing'?
Heading is the direction the bow points; bearing is the direction of an external object measured from the vessel or from north
Special marks
What should you do with a yellow special mark?
Check the chart and current publication to identify its purpose, limits and route implication
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Day Skipper33
Show this course as a focused listWhat colour is a port-hand mark in IALA Region A?What is an isophase light?How do you calculate tidal height for a simple depth check?Where can I take a free Day Skipper theory mock test?What does a yellow flag mean on a boat?For practical Mercator chartwork, one minute on the nearby latitude scale represents what distance?On a vessel's sidelights, what colour marks the starboard side?What is the 'draught' of a vessel?What does a halyard do?What is 'leeward' and how is it pronounced?What is 'freeboard'?What is the 'kicking strap' (vang) used for?What does 'abeam' mean?What is the difference between a 'shroud' and a 'stay'?What does amidships mean?When facing forward, which side of the boat is 'port'?Which lifejacket level is typically intended for coastal and offshore use?Under MARPOL, deliberate discharge at sea is prohibited for which type of garbage?Two sailing vessels are approaching each other. Vessel A is on port tack, Vessel B is on starboard tack. Who gives way?When entering harbour from seaward in Region A, what colour marks should be on your port side?What is 'variation' in compass work?What does 'Fl(3) W 15s' mean on a chart?What is Chart Datum approximately equal to in most UK tidal waters?What is the difference between a DR position and an EP?What does a large-scale chart show?What does 'veering' mean in weather terminology?What does APEM stand for in passage planning?A yacht is under sail and its propulsion machinery is not being used. Which Rule 35 signal should it make in restricted visibility?Which property most strongly supports considering a suitable nylon product for mooring lines and anchor warps?As an initial guide in moderate conditions, what scope is commonly taught for all-chain cable?Which task are navigators' dividers designed to perform in paper chartwork?On which VHF channel is a voice MAYDAY distress call broadcast?Under the current England marine and coastal wildlife visitor code, how far should a motorised vessel stay from marine wildlife?
Marine Radio22
Show this course as a focused listWhat is the difference between Mayday and Pan-Pan?What is the difference between VHF Channel 16 and Channel 70?You have bought a handheld VHF for your boat. What does holding the SRC primarily prove?What should you do before making a routine marine VHF voice call?What does Say Again request?Which description of Channel 16 is operationally correct?Which phrase correctly introduces your own vessel identity in a routine voice call?A yacht is being driven onto rocks, cannot arrest the approach and needs immediate outside help. Which priority is appropriate?A crew member needs urgent medical advice, but the facts do not yet show grave and imminent danger. Which route fits?Which channel is used for VHF DSC digital signalling?What is an EPIRB's primary alerting function?Which statement correctly distinguishes the simulator's microphone paths?A learner has completed online revision and wants the official SRC assessment. Where is the practical assessment taken?What does PTT mean in normal VHF operation?Why should Over and Out not be combined?What is the defining operating rule for Channel 70?Why should detailed routine traffic move from an initial calling route to a suitable working channel?Which position report gives responders the most usable information when the coordinate is current and verified?Which signal introduces an authorised general navigation-safety message?What does an MMSI identify?What may safely be concluded from an AIS display with no target at the harbour entrance?What matters most when reviewing a spoken radio call?
Coastal Skipper12
Show this course as a focused listWhat is a lee shore and why is it considered dangerous?What is the difference between 'course' and 'track'?In navigation, what is 'fetch'?What does 'making good' a course mean?What is a transit in navigation?What does it mean when a vessel is described as 'making way through the water'?What is the difference between 'heading' and 'bearing'?Under MARPOL Annex V, which garbage must not be deliberately discharged at sea?Two sailing vessels are in sight with collision risk. Vessel A is on port tack and Vessel B is on starboard tack. Who keeps out of the way?Following the charted conventional direction of buoyage in Region A, which normal lateral colour marks the port-hand side of the channel?What Rule 35 signal should a yacht under sail alone make in restricted visibility?Under the current marine and coastal wildlife visitor code for England, how far should a motorised vessel stay from marine wildlife?
Essential Navigation21
Show this course as a focused listWhat should you do with a yellow special mark?What is the safest first shape for a beginner short-trip plan?For the final approach to a harbour, which chart choice gives the strongest starting evidence?In IALA Region A, what do red and green lateral marks depend on?Which sequence correctly turns compatible chart and tide inputs into a depth decision?Which pre-departure weather pack supports a short-trip go/no-go decision?What are the two basic habits behind collision avoidance?Which description best captures pilotage near a harbour?Which set of checks belongs before choosing an anchorage?A familiar short trip is proposed. What is the governing purpose of its passage plan?The plotter position looks precise, but depth and visual marks disagree. What is the safest role for the electronics?Which item belongs in a useful crew briefing?A route crosses an unfamiliar symbol in apparently deep-coloured water. What should you do before relying on the route?What does a north cardinal mark indicate?A shallow-water calculation only just exceeds the chosen requirement. Why must the safety margin remain in the decision?Why must the forecast wind direction be drawn against the actual route?What does constant bearing with decreasing range suggest?Which feature makes a pilotage cue operationally useful?What does scope describe in this small-boat anchoring plan?Why must a round trip appraise the return separately rather than reverse the outward assumptions?Why can zoom level be a navigation trap?
Yachtmaster3
Show this course as a focused listCEVNI20
Show this course as a focused listA learner says, ‘CEVNI is one identical law that gives me permission to use every European waterway.’ Which correction is strongest?A.5 tells vessels not to berth on the side where the board is placed. Which interpretation is complete?An upstream commercial vessel displays the prescribed light-blue board and bright white scintillating light to an approaching downstream vessel. What arrangement is it indicating?A vessel gives one long blast near a blind fairway section. What is the sound signal communicating?What should shape a CEVNI meeting decision before two vessels enter a narrow fairway?A lock gate is moving and red plus green entry lights show. What is the correct decision?What is the safest and most accurate view of a pushed convoy?An A.5 no-berthing sign has an arrow marked 1000 m. What is the correct reading?A sample item shows A.5, an arrow and 1000 m. What should you identify first?A UK applicant has passed the RYA CEVNI test but has not applied for an ICC or supplied boat-category competence evidence. What have they established?B.3b requires a vessel to keep to the starboard side of the fairway. Which response follows the exact instruction?Which statement preserves the exact distinction between CEVNI blue dangerous-goods and authority signals?Which method best separates look-alike CEVNI sound signals?Travelling downstream, you see the prescribed blue-board meeting indication on an upstream vessel's starboard side. What must you avoid?A small craft reaches a lock before a commercial vessel and both will share it. When should the small craft enter?You see a towing leader but cannot find the last section. Which action is unsafe?When is a berth unsuitable despite available space?How should you decide between two technically plausible CEVNI options?Before moving from coastal water into a signed canalised river, what is the safest planning decision?A C.2 board before a bridge shows 3.50 m. What is the defensible pre-entry check for a boat with 3.20 m maximum air draught?
Radar20
Show this course as a focused listWhat does a radar display show?Why can a clean-looking radar display be unsafe?What does a VRM measure?Which factors affect target strength on radar?A relative plot forecasts a CPA of 1.0 M. What does CPA mean here?Why is AIS not a complete traffic picture?What is radar pilotage best used for?What does radar allow in restricted visibility?What is the first step in a radar scenario?Why must a small craft remain in the risk picture when its echo fades in rough water?What does gain primarily affect?What does an EBL measure?What is the safest claim about radar reflectors?What does a plotted TCPA of 30 minutes mean?What should you do with a radar echo that has no AIS label?What is parallel indexing?What is the safest response if CPA is uncertain in fog?How should a crossing contact be assessed?A blank wedge remains on the same relative bearing when the boat changes heading. Which cause should be investigated first?What is the risk of excessive sea clutter suppression?
Powerboat ICC20
Show this course as a focused listWhat is the ICC best described as?Why are pre-departure checks especially important in powerboats?What should be assessed before committing to a slipway launch?What is the safest close-quarters speed principle?What changes most at planing speed?What is the first crew action after someone falls overboard?What should be considered before anchoring?What is safe speed?What should a short powerboat passage plan include?What does Level 2 Powerboat Handling focus on?How should a kill cord be used?Why check the tide window before launch?Why use short bursts of power?When should speed be reduced near a hazard?A person overboard is alongside the recovery point. Which engine control is essential before bringing them within reach of the propeller?What confirms an anchor is probably holding?What should powerboats do in a head-on situation?Why plan the return before leaving?What should be checked before relying on an ICC abroad?What should be included in a powerboat fuel check?