Complete USCG Captain's License
Exam Prep Guide
Everything you need to pass the USCG captain's license exam — all 4 modules, top-tested topics, chart plotting formulas, stability concepts, common traps, and a proven 4-week study plan.
OUPV (6-Pack) vs. Master License — What's the Difference?
The first decision every prospective captain faces: which license do you actually need? The USCG offers multiple license pathways, but for most recreational boaters and small charter operators, it comes down to two options: the OUPV (Operator of Uninspected Passenger Vessels) and the Master license, both limited to vessels up to 100 gross tons.
OUPV — The 6-Pack License
The OUPV is the entry-level commercial captain's license. It authorizes you to operate uninspected vessels carrying up to 6 passengers for hire. Routes are limited to within 100 miles of shore (or up to 200 miles with a Near Coastal route) on ocean waters, or any distance on inland waters. Sea-time requirement: 360 days on the water, with at least 90 days in the past 3 years.
Master 100-Ton License
The Master license removes the 6-passenger cap, allowing you to operate inspected passenger vessels. This is required for ferry operations, dinner cruises, whale-watching trips, or any commercial operation carrying more than 6 paying passengers. Sea-time requirement: 720 days on the water, with at least 360 days of service as an able seaman or equivalent.
Exam Differences
Both licenses use the same 4-module exam structure with a 70% passing threshold per module. The core subject matter is identical. Master license candidates may face additional modules for inspected vessel operations, passenger vessel safety, or specific endorsements (towing, sailing, etc.) depending on their intended operations. For most candidates, the practical difference in exam difficulty is minimal — the 4-module battery is the main event.
| Feature | OUPV (6-Pack) | Master 100-Ton |
|---|---|---|
| Passenger limit | Up to 6 passengers | More than 6 (inspected vessels) |
| Sea-time required | 360 days | 720 days |
| Route limit | Up to 100 nm offshore | Up to 100 nm offshore (same base) |
| Vessel type | Uninspected only | Inspected passenger vessels |
| Core exam modules | 4 modules (same) | 4 modules (same) + possible add-ons |
| Passing score | 70% per module | 70% per module |
How the USCG Exam Is Administered
Understanding the logistics of the exam before you sit down to study makes the entire process less intimidating. The USCG licensing exam is not a mystery black box — it is a known, public system with documented rules.
The National Maritime Center (NMC)
The NMC is the federal agency that processes all merchant mariner credentials, including captain's licenses. They set the exam content, maintain the official question bank, and issue the final credential. You submit your application (with sea-time documentation, first-aid/CPR certification, physical, drug test, and background check) to the NMC before or after testing, depending on your path.
Regional Examination Centers and Approved Facilities
The actual exam is taken at a Regional Examination Center (REC) or an NMC-approved third-party testing facility (often affiliated with maritime schools or captain's license prep courses). Most candidates who attend a prep course take the exam at the school's facility immediately after the course — this is the most common path. Walk-in testing at REC offices is available in some locations but requires advance scheduling. Check the NMC website for current REC locations and hours.
The Question Bank — Your Biggest Study Asset
The USCG publishes the entire exam question bank publicly on the NMC website. Every question that can appear on your exam is in that database. The exam randomly selects questions from this bank for each module. This means studying the actual exam questions — not just textbooks — is the most efficient preparation strategy available. Many candidates who fail the exam did not realize the question bank was public.
Retake Policy
If you fail one or more modules, you do not retake the entire exam. You retake only the failed module(s). There is a waiting period between retakes, and the number of attempts before additional requirements (such as remedial training) kick in is limited. Pass your modules one by one if needed — but the goal is to pass all four on the first attempt with proper preparation.
The Four Exam Modules — Complete Breakdown
The USCG captain's license exam consists of four modules. You must pass all four — a 70% score on each — to receive your credential. Here is exactly what each module tests and what you must know.
| Module | Questions | To Pass (70%) | Format | Primary Topics |
|---|---|---|---|---|
| Rules of the Road | 33 | 24 correct | Multiple choice | COLREGS, Inland Rules, lights, shapes, sound signals |
| Deck General Safety | 33 | 24 correct | Multiple choice | Safety equipment, fire, stability, MARPOL, regulations |
| Navigation General | 33 | 24 correct | Multiple choice | Compass, tides, chart symbols, speed/time/distance, weather |
| Chart Plotting | 3 problems | All 3 pass | Hands-on (paper chart) | DR, fixes, set/drift, course, ETA calculations |
Module 1: Rules of the Road
This module is heavy on pure memorization. The COLREGS (International Regulations for Preventing Collisions at Sea) and the U.S. Inland Rules govern vessel behavior in every situation — and the exam tests both. You must know: which vessel is give-way and which is stand-on in every encounter type (head-on, crossing, overtaking); exact light configurations for power-driven vessels, sailing vessels, vessels not under command, restricted in ability to maneuver, constrained by draft, fishing, towing, and at anchor; sound signals for maneuvering, restricted visibility, distress, and pilot vessels; and the narrow channel, traffic separation scheme, and restricted visibility rules.
Module 2: Deck General Safety
Deck General covers the operational side of seamanship. Major topic areas include: fire fighting (classes of fire, extinguisher types, PASS technique, fire prevention); life-saving appliances (life jackets, life rings, EPIRBs, flares, survival craft); MARPOL (marine pollution regulations — oil discharge rules, garbage management, sewage); vessel stability concepts (G, B, M, GM, free-surface effect); federal regulations under CFR Title 46 (vessel inspection, manning, equipment requirements); and emergency procedures (man overboard, flooding, grounding).
Module 3: Navigation General
Navigation General is the theoretical counterpart to Chart Plotting. It covers: compass correction (variation, deviation, and the TVMDC mnemonic); tides (predicting high/low water, tidal range, rule of twelfths); currents (tidal vs. non-tidal, set and drift); chart symbols and the use of Chart No. 1; speed/time/distance mathematics; weather interpretation (isobars, fronts, Beaufort scale, storm signals); piloting concepts (bearing, range, danger bearing, running fix); and basic celestial navigation terminology.
Module 4: Chart Plotting
Chart Plotting is a hands-on practical examination. You are given a printed NOAA nautical chart, parallel rulers (or a course plotter), and dividers. You must solve 3 problems that typically involve: plotting a dead-reckoning (DR) track from a given position; determining the effect of current (set and drift) and finding your actual position; and calculating course to steer, ETA, or distance off. Every answer must be within acceptable tolerances. Practice this physical skill — it cannot be mastered by reading alone.
Test-Taking Strategy for the USCG Exam
Knowing the material and passing the exam are related but distinct skills. The USCG exam has specific characteristics that reward strategic test-taking alongside deep knowledge.
Process of Elimination
Many USCG exam questions include one or two obviously wrong answers — eliminate those first. The question bank is public, and many answers are clearly designed to test whether you know a specific number (22.5 degrees vs. 45 degrees, for example) or a specific word (the "give-way" vessel must "take early and substantial action" — every word matters). When you are unsure, eliminate the clearly wrong options and select from the remaining choices.
Time Management
You are not racing a clock on the knowledge modules — take your time. Read every question twice. Many candidates miss questions because they misread a key word: "NOT," "EXCEPT," "INLAND ONLY," "INTERNATIONAL RULES." On Chart Plotting, manage your time more actively. Each problem requires multiple steps. Work methodically: plot, calculate, verify. Do not rush the plotting — an error in the first step cascades through the entire problem.
Know the Question Bank Cold
The single highest-yield study activity for the knowledge modules is working through the official USCG question bank — all questions, all modules, repeatedly, until you can answer each one instantly. Because the exam draws directly from this bank, full familiarity with every question and answer is the best possible preparation. Question bank mastery beats textbook reading for the purpose of passing the exam.
Flag and Return
When you encounter a question that genuinely stumps you, flag it and move on. Answer every question you know, then return to the flagged ones. Often, a later question in the same module will jog your memory on an earlier one. Never leave a question blank — there is no penalty for wrong answers, so guess strategically if you must.
COLREGS vs. Inland — Always Check
One of the most common sources of careless errors: a question specifies "under International Rules" or "under Inland Rules" and you answer for the wrong set. Some rules differ between COLREGS and Inland Rules — particularly for sound signals, certain light configurations, and the narrow channel rule. Read every Rules of the Road question for which ruleset applies before answering.
Top 20 Must-Know COLREGS Rules for the Exam
The Rules of the Road module draws from a large question bank, but the highest-frequency topics cluster around a core set of rules. Master these 20 and you will handle the majority of the exam.
Steering and Sailing Rules (The Big Picture)
- Rule 2Responsibility — The rules do not excuse a departure from them when necessary to avoid immediate danger. Know the "general prudential rule" exception and when it applies.
- Rule 5Lookout — Every vessel must keep a proper lookout by sight AND hearing at all times. No exceptions, no conditions.
- Rule 6Safe Speed — Every vessel must proceed at a safe speed. Factors include visibility, traffic density, maneuverability, and for radar-equipped vessels, radar characteristics and sea state.
- Rule 8Action to Avoid Collision — Action must be large enough to be readily apparent, taken in ample time, and must not result in another close-quarters situation.
- Rule 9Narrow Channels — Vessels shall keep to the starboard side. Vessels under 20 meters or sailing vessels shall not impede vessels that can only navigate in the channel.
- Rule 13Overtaking — Any vessel overtaking any other shall keep out of the way. You are overtaking if you approach from more than 22.5 degrees abaft the other vessel's beam.
- Rule 14Head-On Situation — Both vessels alter course to starboard so each passes on the port side of the other. Applies when vessels meet head-on or nearly so.
- Rule 15Crossing Situation — The vessel which has the other on her starboard side shall keep out of the way (give-way). The stand-on vessel is to port of the give-way vessel.
- Rule 16Action by Give-Way Vessel — Take early and substantial action to keep well clear.
- Rule 17Action by Stand-On Vessel — Maintain course and speed. May take action when it becomes apparent the give-way vessel is not acting. Must take action when collision is imminent.
Lights and Shapes
- Rule 23Power-Driven Vessel Underway — Masthead light(s) forward, sidelights (red/green), sternlight (white). Vessels under 50 meters may combine masthead and sternlight into an all-round white light if under 12 meters.
- Rule 25Sailing Vessels Underway — Sidelights and sternlight. May use combined lantern at top of mast. If using engine AND sail, vessel is deemed power-driven and must show a cone point down forward.
- Rule 27Vessels Not Under Command — Two all-round red lights in a vertical line and appropriate sidelights/sternlight when making way. Restricted in Ability to Maneuver (RAM): red-white-red in a vertical line plus diamond-ball-diamond shapes.
- Rule 28Constrained by Draft — All-round red-white-red (like RAM) plus a cylinder shape. International Rules only — no Inland equivalent.
- Rule 30Anchored Vessels — All-round white light forward (or two all-round white lights for vessels over 50m). Anchor ball shape by day. Vessels over 100m must also illuminate their decks.
Sound Signals
- Rule 34Maneuvering and Warning Signals — 1 short = altering course to starboard; 2 shorts = altering course to port; 3 shorts = operating astern propulsion; 5 or more shorts = doubt or danger. International Rules: 1 and 2 shorts are intent signals. Inland Rules: 1 and 2 shorts are agreement signals (propose-agree exchange).
- Rule 35Sound Signals in Restricted Visibility — Power-driven vessel making way: 1 prolonged every 2 minutes. Power-driven vessel stopped: 2 prolonged every 2 minutes. Sailing vessel underway: 1 prolonged + 2 short every 2 minutes. Vessel at anchor: rapid ringing of bell for 5 seconds every minute.
- Rule 36Signals to Attract Attention — Any light or sound signal that cannot be confused with an aid to navigation. Caution: a vessel must not use signals that could be confused with a distress signal.
- Rule 37Distress Signals — The complete list is in Annex IV. Key signals: SOS by any means, MAYDAY by radio, red parachute or hand-held flare, orange smoke, flames on the vessel, continuous sounding of fog signal apparatus.
- Rule 18Responsibilities Between Vessels — The hierarchy: vessel not under command has right of way over all. Then RAM, then constrained by draft, then fishing, then sailing, then power-driven. Every vessel avoids impeding seaplanes. Know this hierarchy cold.
Must-Know Chart Plotting Formulas
Chart Plotting separates candidates who prepare physically from those who only study reading material. You must be able to execute these calculations accurately on paper with real tools. Know the formulas cold, then practice until the physical process is automatic.
TVMDC — Compass Correction
TVMDC is the mnemonic for the five elements of compass correction:
Apply variation and deviation carefully. East errors make the compass read high (compass heading is greater than true), so you subtract when converting compass to true. West errors make the compass read low. Get this wrong once on exam day and you will know why it matters.
Speed, Time, and Distance
The most common error here is using hours instead of minutes. The formula uses minutes (60 minutes in an hour = the "60" factor). Convert all times to minutes before solving. Example: a vessel traveling at 8 knots for 45 minutes covers (8 x 45) / 60 = 6 nautical miles.
Set and Drift (Current Effect)
Remember: current "sets" in the direction it flows TOWARD, not from. A northerly current sets north. Wind is described by where it comes FROM. Know this distinction — the exam will test it.
Running Fix and Advancing a LOP
A running fix uses two bearings on the same object taken at different times, with the vessel's track plotted between them. To advance a Line of Position (LOP): draw the course line from any point on the first LOP, measure the distance traveled in the elapsed time, and draw a parallel line through that endpoint. The intersection of the advanced LOP and the second LOP is your running fix. Label all LOPs with time, bearing, and object name.
| Formula | Expression | Common Trap |
|---|---|---|
| Compass Correction (T to C) | T ± V = M ± D = C | Applying E/W in wrong direction |
| Distance | D = (S x T) / 60 | Using hours instead of minutes |
| Speed | S = (60 x D) / T | Forgetting to convert time |
| Time | T = (60 x D) / S | Leaving answer in minutes (convert to H:MM) |
| Drift (current speed) | Drift = (DR-to-Fix Distance) / elapsed hours | Confusing set direction (toward, not from) |
| Course to Steer (with current) | Vector triangle: vessel + current = actual track | Forgetting to apply leeway separately |
Critical Stability Concepts for the Exam
Vessel stability questions appear primarily in Deck General Safety and require understanding of the relationships between several key concepts. This is a domain where conceptual understanding beats memorization — if you understand why a vessel becomes unstable, you can answer questions you have never seen before.
The Stability Triangle: G, B, and M
Three points define a vessel's stability picture. G (center of gravity) is the point through which all the vessel's weight acts. B (center of buoyancy) is the geometric center of the underwater volume — it shifts as the vessel heels. M (metacenter) is the point where a vertical line through the shifted B intersects the vessel's centerline when heeled to small angles. The height of M above G — called GM, or metacentric height — is the fundamental measure of initial stability.
- •Positive stability (GM positive): M is above G. The vessel returns to upright after a heel. A larger GM means a stiffer vessel that resists heel — but a very large GM produces uncomfortable snap-rolling.
- •Neutral stability (GM zero): G and M coincide. The vessel has no tendency to return to upright or to capsize — it stays at whatever angle it reaches.
- •Negative stability (GM negative): G is above M. The vessel has a tendency to heel and capsize. It is dangerous at any angle of heel.
Free-Surface Effect
Free-surface effect is one of the most heavily tested stability topics. When a tank is partially filled with liquid, the liquid shifts to the low side when the vessel heels. This shifting mass raises the effective center of gravity — reducing GM — even though the total weight has not changed. A free surface in a tank is equivalent to raising G by the free-surface correction (FSC). Multiple free surfaces in multiple tanks compound the effect. The only way to eliminate free-surface effect in a tank is to empty it completely or fill it completely.
Effect of Adding, Removing, or Shifting Weight
The exam frequently presents scenarios asking how a weight change affects stability. The rules:
- •Adding weight above G raises G, reducing GM (decreasing stability).
- •Adding weight below G lowers G, increasing GM (increasing stability).
- •Removing weight above G lowers G, increasing stability. Removing weight below G raises G, decreasing stability.
- •Shifting weight upward raises G and decreases stability. Shifting weight downward lowers G and increases stability.
- •Shifting weight transversely (off-center) creates a list — the vessel heels toward the side the weight was moved to.
Righting Arm and Righting Moment
The righting arm (GZ) is the horizontal distance between G and the vertical line through B when the vessel is heeled. The righting moment is GZ multiplied by displacement (GZ x W). A stability curve plots GZ against angle of heel. The area under the curve represents the vessel's range of positive stability. When GZ reaches zero at a large angle of heel, the vessel will capsize if heeled beyond that point — even momentarily. Know how to read a stability curve and what happens at the point of vanishing stability.
Common Exam Traps and Gotchas
These are the patterns that trip up prepared candidates who know the material but miss the specific phrasing or context that changes the correct answer.
COLREGS vs. Inland — Read the Question
Multiple questions specify which ruleset applies. Under Inland Rules, maneuvering sound signals operate as a propose-and-agree system. Under International (COLREGS), they are action signals (you signal what you ARE doing, not what you intend). A question about "1 short blast" under Inland Rules and under International Rules has different correct answers. Always note the ruleset before selecting your answer.
22.5 Degrees Abaft the Beam — Not "Behind"
The overtaking rule (Rule 13) applies when a vessel approaches from more than 22.5 degrees abaft the beam of the vessel ahead. The question bank tests the exact angle. "Abaft the beam" means behind 90 degrees from the beam. 22.5 degrees further back than that defines the sector within which you are officially overtaking. Know the number — 22.5 — not just the concept.
Set Direction — Toward, Not From
Current set is described as the direction the current flows TOWARD. A northerly current sets to the north (toward north). Wind is described by where it comes FROM — a northerly wind blows FROM the north. These opposite conventions are tested regularly, often in the same question to see if you conflate them.
Free-Surface Effect Does Not Require More Weight
A common wrong answer on stability questions involves adding liquid to a tank to improve stability. A partially-filled tank with free surface creates a virtual rise in G, reducing GM. A tank that goes from partially full to completely full eliminates the free surface entirely — and can actually improve stability. Adding liquid to an already partially-full tank does not eliminate the free surface, and the increase in weight may raise G further. Know the nuance.
Compass Error Direction (East vs. West)
The mnemonic "Compass Error West, Compass Best; Compass Error East, Compass Least" means: when your compass error (variation + deviation combined) is West, the compass reading is higher (best = largest number) than true. When East, the compass reading is lower (least) than true. Candidates who reverse this fail multiple TVMDC questions. Practice the formula in both directions until the direction of correction is automatic.
Chart Plotting: Units and Scale
On the chart plotting exam, measure distances using the latitude scale on the sides of the chart (1 minute of latitude = 1 nautical mile). Do NOT use the longitude scale for distance — longitude minutes vary in length with latitude. Also confirm whether a speed/distance problem uses nautical miles and knots (the default for maritime navigation) vs. statute miles and mph (which some questions introduce to test unit awareness).
Recommended Study Resources
The right resources make the difference between months of scattered studying and a focused 4-week sprint. Here are the materials that matter most, in order of impact.
Official USCG Question Bank (Free — NMC Website)
The most important resource available. The NMC publishes every question that can appear on the exam. Download the question bank for each module and work through all of them. Flag questions you miss and return to them. A candidate who knows the entire question bank will pass — full stop. Do not skip this resource thinking textbooks are sufficient.
USCG Navigation Rules and Regulations Handbook
The authoritative text for both the COLREGS (Annexes I through IV included) and the Inland Navigation Rules. Available free as a PDF from the USCG and inexpensively as a physical book. Reading the actual rules — not summaries — ensures you encounter the exact language the exam uses. The exam quotes from this document directly.
Chapman Piloting, Seamanship and Small Boat Handling
The most comprehensive seamanship reference in American boating. Chapman's covers navigation, anchoring, weather, stability, safety equipment, rules of the road, and boat handling in depth. It is the go-to reference for Deck General and Navigation General concepts. While dense, the relevant chapters (navigation, stability, safety, rules) provide the conceptual foundation that makes the question bank make sense.
NauticEd Online Courses
NauticEd offers structured online courses covering the USCG exam curriculum with embedded quizzes and practice tests. The structured format is helpful for candidates who need a guided curriculum rather than self-directed study. Particularly useful for Navigation General topics like tides, currents, and compass correction where a visual, step-by-step explanation accelerates comprehension.
NOAA Nautical Charts — Physical Practice Charts
For Chart Plotting, download or purchase the chart used by your local exam center (often Chart 12221 — Chesapeake Bay or similar training charts) and practice on real paper with real tools. Parallel rulers or a course plotter, dividers, and a sharp pencil. You cannot develop the physical skill of plotting on a screen — practice on paper. Practice at least 10-15 complete plotting problems before exam day.
Captain's License Prep Courses (In-Person)
Many maritime schools offer 5-8 day intensive prep courses that cover all four modules and allow you to test immediately after completion at the school's facility. These courses are efficient for candidates who prefer a structured classroom environment and want to compress their preparation into a single week. The best schools provide chart plotting equipment, practice tests drawn from the actual question bank, and testing immediately after the course while the material is fresh.
4-Week Study Schedule
This schedule assumes approximately 1.5 to 2 hours of focused study per day, 5 days per week. Adjust the pace based on your prior maritime experience. Candidates with active sea time or prior exposure to rules of the road may compress Weeks 1-2 and spend more time on Chart Plotting.
| Week | Primary Focus | Daily Activities | End-of-Week Target |
|---|---|---|---|
| Week 1 | Rules of the Road — Core Rules COLREGS Rules 1-19: steering and sailing rules, right-of-way hierarchy | Days 1-2: Read Navigation Rules book, Rules 1-18. Days 3-4: Work through USCG question bank — Rules of the Road section. Day 5: Review missed questions; create personal flashcards for rules with specific numbers (22.5°, Rule 18 hierarchy). | Score 75%+ on Rules of the Road practice test (knowledge module questions only) |
| Week 2 | Rules of the Road — Lights, Shapes, Sound COLREGS Rules 20-37 + Annexes; complete module mastery | Days 1-2: Read Rules 20-37; draw light configurations from memory for each vessel type. Days 3-4: Complete all Rules of the Road question bank questions again; focus on lights, shapes, and sound signals. Day 5: Full timed Rules of the Road practice exam; review every missed question. | Score 80%+ on full Rules of the Road module; begin Deck General overview |
| Week 3 | Deck General Safety + Navigation General Safety equipment, fire, stability, MARPOL; compass, tides, currents, chart symbols | Days 1-2: Deck General — Chapman's relevant chapters (safety, stability, regulations). Work question bank for Deck General. Days 3-4: Navigation General — compass correction (TVMDC), tides (rule of twelfths), speed/time/distance math. Question bank for Navigation General. Day 5: Practice exams for both modules; begin first chart plotting practice problem. | Score 75%+ on both Deck General and Navigation General practice tests; complete 3 chart plotting problems |
| Week 4 | Chart Plotting Intensive + Full Review Physical plotting skill development; full-exam simulations | Days 1-2: Chart plotting intensive — complete 5+ full plotting problems per day on paper. Focus on TVMDC, set/drift, running fix, ETA calculations. Days 3-4: Full four-module practice exams timed. Address any weak areas in knowledge modules. Day 5: Light review only; pack exam supplies. Exam day prep: 2 sharp pencils, parallel rulers, dividers, approved calculator. | All 4 modules scoring 80%+ on practice; chart plotting problems completing accurately and confidently |
Study Schedule Notes
- •Never skip a day of chart plotting practice in Week 4. The physical skill deteriorates quickly without practice.
- •If you are struggling with one module after Week 2, add 30 minutes per day dedicated to that module throughout the remaining weeks.
- •Candidates with prior boating experience can compress Rules of the Road to 1 week and allocate the saved time to chart plotting.
- •Get all your paperwork (sea-time logs, physical, drug test, first aid/CPR certification) organized before Week 1 so credential processing does not delay your license after you pass.
Frequently Asked Questions
Answers to the most common questions from candidates preparing for the USCG captain's license exam.
Q.What is the difference between the OUPV and Master captain's license exam?
The OUPV (6-Pack) license limits you to vessels under 100 GRT carrying up to 6 passengers for hire. The Master license removes the 6-passenger cap and allows operation of inspected passenger vessels. Both licenses use the same 4-module exam with the same 70% passing threshold. Sea-time requirements differ: OUPV requires 360 days, Master 100-ton requires 720 days. The core exam content is identical for both — the difference is in what you are qualified to operate afterward.
Q.How is the USCG captain's license exam administered?
The exam is administered by the National Maritime Center (NMC) at Regional Examination Centers (RECs) or NMC-approved testing facilities. Knowledge modules (Rules of the Road, Deck General, Navigation General) are taken on computer. Chart Plotting is a hands-on test on paper with real NOAA charts and plotting tools. Most candidates test at a maritime school immediately after completing a prep course. The official USCG question bank — which the exam draws from directly — is publicly available on the NMC website.
Q.What is the passing score on each USCG exam module?
You must score at least 70% on each module. For the 33-question knowledge modules, that means 24 correct answers out of 33. Chart Plotting requires successfully completing all 3 problems within accepted accuracy tolerances. A failure in any single module means retaking only that module — not the entire exam.
Q.How many questions are on each USCG exam module?
Rules of the Road, Deck General Safety, and Navigation General each contain 33 multiple-choice questions. Chart Plotting consists of 3 practical problems on a printed NOAA nautical chart. All questions in the knowledge modules are drawn randomly from the official USCG question bank for each testing session.
Q.What are the most important COLREGS rules to know for the exam?
Highest-frequency topics: the Rule 18 hierarchy (NUC, RAM, constrained by draft, fishing, sailing, power-driven), the crossing rule (Rule 15 — give-way to vessel on your starboard), the overtaking rule (Rule 13 — 22.5 degrees abaft the beam), sound signals under Rules 34 and 35 (especially the difference between COLREGS and Inland Rules), light configurations for power-driven vessels (Rule 23), NUC and RAM lights (Rule 27), and anchor lights (Rule 30). Rule 2 (responsibility) appears frequently and tests whether you understand when to deviate from the rules.
Q.What chart plotting formulas must I know for the USCG exam?
The three core frameworks: TVMDC for compass correction (True + or minus Variation = Magnetic + or minus Deviation = Compass); 60D = ST for speed/time/distance (D = distance in nm, S = speed in knots, T = time in minutes); and the set-and-drift vector (plot DR position, plot actual fix, measure bearing and distance from DR to fix for set and drift). Also know how to advance a Line of Position for a running fix and how to solve a current triangle to find course to steer.
Q.What stability concepts are tested on the USCG exam?
Key topics: the G-B-M relationship and what GM means for stability (positive, neutral, negative); free-surface effect (partial tank fill raises virtual G, reducing GM — only filling completely or emptying eliminates it); the effect of adding, removing, and shifting weight on G and therefore GM; righting arm (GZ) and the stability curve; and range of positive stability vs. initial stability. Questions often present loading scenarios and ask whether stability increases or decreases.
Q.What study resources are recommended for the USCG captain's license exam?
In order of impact: (1) Official USCG question bank (free, NMC website — the exam draws directly from it); (2) USCG Navigation Rules and Regulations Handbook (authoritative text for COLREGS and Inland Rules); (3) Chapman Piloting and Seamanship (comprehensive reference for Deck General and Navigation General concepts); (4) NauticEd online courses (structured curriculum with practice tests); (5) physical NOAA charts with parallel rulers and dividers for chart plotting practice; (6) in-person prep courses at maritime schools (most efficient for candidates who want a compressed timeline).
Ready to Start Practicing?
NailTheTest gives you interactive practice questions drawn from the official USCG question bank, organized by module, with instant explanations for every answer. Study smarter and pass on the first attempt.
Start Practicing FreeAll 4 modules — Rules of the Road, Deck General, Navigation General, and Chart Plotting