# USCGQ.com > Practice questions and answers for U.S. Coast Guard merchant mariner license exams (deck, engineering, GMDSS) and FCC commercial radio operator licenses: 26,907 questions released by the Coast Guard and the FCC, refreshed from the National Maritime Center's 2026 sample examinations. Every question page shows the question, its four choices, the correct answer, the USCG reference and the illustration where one exists (the answer is metered for visitors and open to verified crawlers). Module hub pages list every question in a module. Practice-test pages list the modules of each license exam with their question counts. The site has helped mariners since 2008 and is not affiliated with the U.S. Coast Guard. ## Question modules - [Deck](https://uscgq.com/question/deck/): The Deck pool holds the current U.S. Coast Guard questions for every deck credential, from Able Seaman and the OUPV six-pack up to unlimited Master. Each question is multiple choice with four options, graded instantly, with the USCG reference shown where one exists. - [Deck: Rules of the Road](https://uscgq.com/question/deck/1/): 1,168 questions. Steering and sailing rules, lights and shapes, and sound signals, covering both the international COLREGs and the U.S. Inland Rules. This is the strictest module on the deck exam: it requires 90 percent to pass. - [Deck: Deck General](https://uscgq.com/question/deck/2/): 5,775 questions. Seamanship in the broad sense: marlinespike, ground tackle and anchoring, mooring and towing, weather, stability basics, and day-to-day vessel operations. - [Deck: General Navigation](https://uscgq.com/question/deck/3/): 2,639 questions. Chart reading, the U.S. Aids to Navigation System, compass error, tides and currents, and the standard navigation publications. - [Deck: Safety](https://uscgq.com/question/deck/4/): 3,245 questions. Firefighting, lifesaving appliances and survival craft, emergency procedures, first aid, and pollution prevention regulations. - [Deck: Navigation Problems](https://uscgq.com/question/deck/5/): 2,005 questions. Worked chart problems: plotting courses and fixes, time, speed, and distance, set and drift, and compass error corrections. - [Engine](https://uscgq.com/question/engine/): The Engine pool holds the current U.S. Coast Guard questions for engineering credentials, from QMED ratings through DDE and Assistant Engineer up to Chief. Answer any question to see the correct choice instantly. - [Engine: General Subjects](https://uscgq.com/question/engine/11/): 1,465 questions. General engineering knowledge: watchkeeping, pumps and piping systems, hydraulics, instrumentation, and shipboard maintenance. - [Engine: Electricity](https://uscgq.com/question/engine/12/): 1,595 questions. Marine electrical systems: motors and generators, switchboards and distribution, batteries, electronics, and control engineering. - [Engine: Steam Plants](https://uscgq.com/question/engine/13/): 1,029 questions. Boilers, steam turbines, condensate and feed systems, and the operation and maintenance of steam propulsion plants. - [Engine: Motor Plants and Auxiliary Boilers](https://uscgq.com/question/engine/14/): 1,433 questions. Diesel engine theory and operation, fuel and lubrication systems, starting and reversing, and auxiliary boilers. - [Engine: Engineering Safety](https://uscgq.com/question/engine/15/): 1,109 questions. Engine room safety: firefighting and fire prevention, confined space entry, pollution regulations, and safe work practices. - [Engine: Refrigeration AC](https://uscgq.com/question/engine/16/): 623 questions. Refrigeration cycles and components, compressors, refrigerants, and marine air conditioning systems. - [Engine: Gas Turbines](https://uscgq.com/question/engine/17/): 335 questions. Gas turbine theory, construction, operation, and the support systems found in gas turbine propulsion plants. - [GMDSS](https://uscgq.com/question/gmdss/): These are the published GMDSS Element 7 questions covering radio operating practices: DSC, satellite communications, NAVTEX, EPIRBs, and distress procedures. The GMDSS Radio Operator exam draws from this pool. - [GMDSS: Element 7](https://uscgq.com/question/gmdss/1/): 600 questions. GMDSS radio operating practices: digital selective calling, INMARSAT, NAVTEX, EPIRBs, search and rescue transponders, and distress, urgency, and safety procedures. - [GMDSS](https://uscgq.com/question/gmdss_e3/): These are the published GMDSS Element 3 questions covering general radiotelephone operator knowledge: radio law, operating procedures, and equipment fundamentals. - [GMDSS: Element 3](https://uscgq.com/question/gmdss_e3/1/): 605 questions. General radiotelephone operator knowledge: radio law and regulations, operating procedures, and radio equipment fundamentals. - [Marine Radio Operator Permit](https://uscgq.com/question/mrop/): The complete FCC Element 1 question pool for the Marine Radio Operator Permit (MROP): basic radio law and operating practice every maritime radio operator must know. Element 1 is also the written element shared by the GMDSS Radio Operator and Maintainer licences. - [Marine Radio Operator Permit: Element 1](https://uscgq.com/question/mrop/1/): 144 questions. Basic radio law and operating practice for the Marine Radio Operator Permit: equipment and licence requirements, watchkeeping, distress and safety procedures, and frequency rules. The exam asks 24 questions from this pool; 18 correct passes. - [GMDSS](https://uscgq.com/question/gmdss_e7r/): The FCC Element 7R pool for the Restricted GMDSS Radio Operator licence: the GMDSS operating procedures that apply to ships sailing only in sea area A1, with DSC, VHF and EPIRB practice. - [GMDSS: Element 7R](https://uscgq.com/question/gmdss_e7r/1/): 300 questions. Restricted GMDSS operating practices for sea area A1 vessels: VHF DSC, distress alerting, EPIRBs and SARTs, and watchkeeping. The exam asks 50 questions; 38 correct passes. - [Ship Radar Endorsement](https://uscgq.com/question/radar/): The FCC Element 8 pool for the Ship Radar Endorsement: radar theory, installation, servicing and maintenance of ship radar equipment used for navigation. - [Ship Radar Endorsement: Element 8](https://uscgq.com/question/radar/1/): 300 questions. Ship radar techniques: radar principles, transmitters and receivers, antennas, displays, installation, servicing and safety. The exam asks 50 questions; 38 correct passes. - [GMDSS Maintainer](https://uscgq.com/question/gmdss_e9/): The FCC Element 9 pool for the GMDSS Radio Maintainer licence: radio system theory, amplifiers, power sources, troubleshooting, digital theory and GMDSS equipment regulations for sea areas A3 and A4. - [GMDSS Maintainer: Element 9](https://uscgq.com/question/gmdss_e9/1/): 299 questions. GMDSS maintenance practices and procedures: VHF, MF-HF and satellite equipment, power supplies, digital theory, troubleshooting and the regulations for sea areas A3 and A4. The exam asks 50 questions; 38 correct passes. ## Practice tests by license - [All licenses](https://uscgq.com/practice-tests): every module of every deck and engineering license exam from the NMC's 2026 sample examinations. - [Deck Officer Endorsements practice test](https://uscgq.com/practice-tests/deck-officer-endorsements): 3 modules (Q100–Q460), 118 questions. - [Master/Chief Mate of Unlimited Tonnage practice test](https://uscgq.com/practice-tests/master-chief-mate-of-unlimited-tonnage): 9 modules (Q101–Q109), 360 questions. - [Second/Third Mate of Unlimited Tonnage practice test](https://uscgq.com/practice-tests/second-third-mate-of-unlimited-tonnage): 7 modules (Q111–Q117), 320 questions. - [Master Less than 500-1600 Gross Registered Tons practice test](https://uscgq.com/practice-tests/master-under-500-1600-grt): 14 modules (Q120–Q389), 580 questions. - [Second Mate to Master Less than 1600 Gross Registered Tons practice test](https://uscgq.com/practice-tests/second-mate-to-master-under-1600-grt): 2 modules (Q130–Q131), 80 questions. - [Master TV to Master Less than 500 Gross Registered Tons Oceans or Near Coastal practice test](https://uscgq.com/practice-tests/master-tv-to-master-under-500-grt-oceans-or-near-coastal): 4 modules (Q132–Q135), 105 questions. - [Mate Less than 500-1600 Gross Registered Tons practice test](https://uscgq.com/practice-tests/mate-under-500-1600-grt): 15 modules (Q136–Q393), 699 questions. - [Master or Mate Less than 200 Gross Registered Tons practice test](https://uscgq.com/practice-tests/master-or-mate-under-200-grt): 11 modules (Q150–Q461), 360 questions. - [Master Less than 100 GRT to Master or Mate Less than 200 GRT Oceans or Near Coastal practice test](https://uscgq.com/practice-tests/master-under-100-grt-to-master-or-mate-under-200-grt-oceans-or-near-coastal): 2 modules (Q156–Q157), 60 questions. - [OUPV to Master or Mate Oceans or Near Coastal Less than 200 GRT practice test](https://uscgq.com/practice-tests/oupv-to-master-or-mate-oceans-or-near-coastal-under-200-grt): 2 modules (Q158–Q159), 80 questions. - [Master Near Coastal Less than 100 Gross Registered Tons practice test](https://uscgq.com/practice-tests/master-near-coastal-under-100-grt): 3 modules (Q160–Q162), 150 questions. - [Master Less than 100 Gross Registered Tons practice test](https://uscgq.com/practice-tests/master-under-100-grt): 6 modules (Q163–Q403), 180 questions. - [OUPV to Master Near Coastal Less than 100 Gross Registered Tons practice test](https://uscgq.com/practice-tests/oupv-to-master-near-coastal-under-100-grt): 1 modules (Q165), 50 questions. - [Operator Uninspected Passenger Vessel Near Coastal practice test](https://uscgq.com/practice-tests/oupv-near-coastal): 2 modules (Q170–Q171), 100 questions. - [Operator Uninspected Passenger Vessels practice test](https://uscgq.com/practice-tests/oupv): 4 modules (Q172–Q358), 120 questions. - [Master Uninspected Fishing Vessels practice test](https://uscgq.com/practice-tests/master-uninspected-fishing-vessels): 7 modules (Q180–Q186), 230 questions. - [Mate Uninspected Fishing Vessels practice test](https://uscgq.com/practice-tests/mate-uninspected-fishing-vessels): 7 modules (Q188–Q194), 235 questions. - [Master/Chief Mate Offshore Supply Vessels practice test](https://uscgq.com/practice-tests/master-chief-mate-osv): 8 modules (Q200–Q207), 325 questions. - [Mate Offshore Supply Vessels practice test](https://uscgq.com/practice-tests/mate-osv): 7 modules (Q209–Q215), 320 questions. - [Limited Operator Uninspected Passenger Vessels practice test](https://uscgq.com/practice-tests/limited-oupv): 3 modules (Q301–Q361), 120 questions. - [Master of Unlimited Tonnage practice test](https://uscgq.com/practice-tests/master-of-unlimited-tonnage): 6 modules (Q302–Q383), 255 questions. - [Mate of Unlimited Tonnage practice test](https://uscgq.com/practice-tests/mate-of-unlimited-tonnage): 5 modules (Q308–Q312), 250 questions. - [Master TV to Master Less than 500 Gross Registered Tons Great Lakes and Inland practice test](https://uscgq.com/practice-tests/master-tv-to-master-under-500-grt-great-lakes-and-inland): 1 modules (Q326), 70 questions. - [Master Less than 100 GRT to Master or Mate Less than 200 GRT Great Lakes and Inland practice test](https://uscgq.com/practice-tests/master-under-100-grt-to-master-or-mate-under-200-grt-great-lakes-and-inland): 1 modules (Q345), 50 questions. - [OUPV to Master or Mate Less than 200 GRT Great Lakes and Inland practice test](https://uscgq.com/practice-tests/oupv-to-master-or-mate-under-200-grt-great-lakes-and-inland): 1 modules (Q346), 70 questions. - [OUPV to Master Less than 100 Gross Registered Tons Great Lakes and Inland practice test](https://uscgq.com/practice-tests/oupv-to-master-under-100-grt-great-lakes-and-inland): 1 modules (Q352), 50 questions. - [First Class Pilot practice test](https://uscgq.com/practice-tests/first-class-pilot): 4 modules (Q370–Q373), 140 questions. - [Master Unlimited Tonnage Rivers practice test](https://uscgq.com/practice-tests/master-unlimited-tonnage-rivers): 3 modules (Q380–Q382), 150 questions. - [Master Less than 500-1600 Gross Registered Tons Rivers practice test](https://uscgq.com/practice-tests/master-under-500-1600-grt-rivers): 3 modules (Q386–Q388), 150 questions. - [Master or Mate Less than 200 Gross Registered Tons Rivers practice test](https://uscgq.com/practice-tests/master-or-mate-under-200-grt-rivers): 2 modules (Q396–Q397), 120 questions. - [Master Less than 100 GRT to Master or Mate Less than 200 GRT Rivers practice test](https://uscgq.com/practice-tests/master-under-100-grt-to-master-or-mate-under-200-grt-rivers): 1 modules (Q400), 50 questions. - [Master Less than 100 Gross Registered Tons Rivers practice test](https://uscgq.com/practice-tests/master-under-100-grt-rivers): 2 modules (Q401–Q402), 120 questions. - [Apprentice Mate (Steersman) of Towing Vessels practice test](https://uscgq.com/practice-tests/apprentice-mate-steersman-of-towing-vessels): 11 modules (Q410–Q421), 469 questions. - [Towing Vessels – Western Rivers practice test](https://uscgq.com/practice-tests/towing-vessels-western-rivers): 4 modules (Q423–Q426), 160 questions. - [Mobile Offshore Drilling Units practice test](https://uscgq.com/practice-tests/modu): 10 modules (Q430–Q441), 499 questions. - [Lifeboatman practice test](https://uscgq.com/practice-tests/lifeboatman): 1 modules (Q445), 50 questions. - [Lifeboatman Limited practice test](https://uscgq.com/practice-tests/lifeboatman-limited): 1 modules (Q447), 50 questions. - [Able Seafarer Unlimited, Limited, Special, Special OSV, Sail, Fishing Industry practice test](https://uscgq.com/practice-tests/able-seafarer-unlimited-limited-special-special-osv-sail-fishing-industry): 2 modules (Q450–Q451), 100 questions. - [Tank Vessel – Assistant practice test](https://uscgq.com/practice-tests/tank-vessel-assistant): 2 modules (Q456–Q457), 99 questions. - [First Assistant Engineer practice test](https://uscgq.com/practice-tests/first-assistant-engineer): 7 modules (Q511–Q517), 489 questions. - [Third Assistant Engineer practice test](https://uscgq.com/practice-tests/third-assistant-engineer): 8 modules (Q531–Q538), 558 questions. - [Chief Engineer – Limited practice test](https://uscgq.com/practice-tests/chief-engineer-limited): 6 modules (Q601–Q606), 419 questions. - [Assistant Engineer – Limited practice test](https://uscgq.com/practice-tests/assistant-engineer-limited): 6 modules (Q610–Q615), 419 questions. - [DDE – Unlimited HP practice test](https://uscgq.com/practice-tests/dde-unlimited-hp): 6 modules (Q620–Q625), 420 questions. - [DDE – 1000/4000 HP practice test](https://uscgq.com/practice-tests/dde-1000-4000-hp): 5 modules (Q630–Q634), 249 questions. - [OSV – Assistant Engineer practice test](https://uscgq.com/practice-tests/osv-assistant-engineer): 4 modules (Q650–Q654), 280 questions. - [OSV – Chief Engineer practice test](https://uscgq.com/practice-tests/osv-chief-engineer): 4 modules (Q680–Q684), 278 questions. - [UFIV – Assistant Engineer practice test](https://uscgq.com/practice-tests/ufiv-assistant-engineer): 3 modules (Q690–Q693), 150 questions. - [UFIV – Chief Engineer practice test](https://uscgq.com/practice-tests/ufiv-chief-engineer): 3 modules (Q694–Q697), 210 questions. - [MODU – Assistant Engineer practice test](https://uscgq.com/practice-tests/modu-assistant-engineer): 3 modules (Q715–Q717), 149 questions. - [MODU – Chief Engineer practice test](https://uscgq.com/practice-tests/modu-chief-engineer): 3 modules (Q730–Q750), 210 questions. - [QMED practice test](https://uscgq.com/practice-tests/qmed): 9 modules (Q800–Q808), 629 questions. ## FCC radio licenses - [FCC commercial radio practice tests](https://uscgq.com/fcc-radio-license-practice-test): which written elements each license needs (MROP, GROL, GMDSS operator, restricted operator, maintainer, ship radar) and the complete FCC question pools for Elements 1, 3, 7 (2021 pool), 7R, 8 and 9. - [GMDSS practice test](https://uscgq.com/gmdss-practice-test): Element 7 (2021 pool) and Element 3. ## Guides - [captains-license-practice-test](https://uscgq.com/captains-license-practice-test): Captains license practice test: OUPV six-pack and Master 100 ton exam modules, passing scores and study plan. - [oupv-license-practice-test](https://uscgq.com/oupv-license-practice-test): OUPV (six-pack) license practice test. - [uscg-rules-of-the-road-practice-test](https://uscgq.com/uscg-rules-of-the-road-practice-test): Rules of the Road practice test (90 percent to pass). - [nav-rules-practice-test](https://uscgq.com/nav-rules-practice-test): Navigation Rules practice test. - [uscg-deck-practice-test](https://uscgq.com/uscg-deck-practice-test): USCG deck license practice test. - [uscg-engineer-license-exam-questions](https://uscgq.com/uscg-engineer-license-exam-questions): USCG engineer license exam questions. - [captains-license-study-guide](https://uscgq.com/captains-license-study-guide): Captains license study guide. - [uscg-exam-questions-and-answers](https://uscgq.com/uscg-exam-questions-and-answers): The complete question bank with answers, by module. - [faq](https://uscgq.com/faq): Frequently asked questions about the site and the exams. - [pricing](https://uscgq.com/pricing): Free daily questions; subscriptions for unlimited practice and timed exams. ## Optional - [Forum archive](https://uscgq.com/forum/): mariner discussions from the site forum. - [Sitemap](https://uscgq.com/sitemap.xml)