ColRegs structure, right-of-way hierarchy, light arcs, sound signals, and Inland vs. International differences — answered entirely from memory.
90%
Passing threshold — 45 of 50 questions
#1
Highest failure rate of all exam sections
0
Reference materials allowed — pure memory
| Part | Rules | Content | Exam Weight |
|---|---|---|---|
| A — General | 1–3 | Application, definitions, general principles of good seamanship | Low |
| B — Steering & Sailing | 4–19 | Conduct of vessels — crossing, overtaking, head-on, restricted visibility | High |
| C — Lights & Shapes | 20–31 | Which lights and shapes to display, when, and arc requirements | High |
| D — Sound & Light Signals | 32–37 | Whistle signals, fog signals, distress signals | Moderate |
| E — Exemptions | 38 | Older vessels grandfathered in under specific conditions | Minimal |
Every vessel gives way to vessels higher on this list. The vessel at the top has the highest right-of-way.
Not Under Command (NUC)
Rule 3(f)
Restricted in Ability to Maneuver (RAM)
Rule 3(g)
Constrained by Draft (CBD)
Rule 3(h) — International only
Engaged in Fishing
Rule 3(d)
Under Sail
Rule 12
Power-Driven Vessel Underway
Rule 18
Seaplane
Rule 18(e)
Critical Exception: Overtaking (Rule 13)
Any vessel overtaking another must keep clear — regardless of its type. An overtaking power vessel must give way to the sailboat it is passing.
Any vessel coming up on another from more than 22.5° abaft the beam is overtaking. Must keep clear until completely past and clear. Doubt = overtaking.
Both vessels alter course to starboard. A vessel is head-on if it can see both sidelights of the other. When in doubt, assume head-on.
The vessel with the other on its starboard side is give-way. Give-way vessel should avoid crossing ahead. Stand-on vessel maintains course and speed.
Take early and substantial action to keep well clear. A late, small alteration does not comply.
Maintain course and speed. May take action once it becomes apparent give-way is not acting. Must take action to avoid collision if necessary.
All vessels proceed at safe speed. Avoid altering course to port for a vessel forward of beam. Avoid altering toward a vessel abeam or abaft.
| Light | Color | Arc | Notes |
|---|---|---|---|
| Masthead (steaming) | White | 225° | Forward, seen from ahead and from each side up to 22.5° abaft beam |
| Sidelights | Red (port) / Green (stbd) | 112.5° each | Red on port, green on starboard, from dead ahead to 22.5° abaft beam |
| Sternlight | White | 135° | Visible from astern, centered aft |
| All-around | White / Red / Green | 360° | Used for anchor lights, fishing lights, NUC balls |
| Towing light | Yellow | 135° | Same arc as sternlight, shown by towing vessel instead of sternlight |
| Topic | Inland Rules | International (ColRegs) |
|---|---|---|
| Meeting head-on | Exchange 1 short blast signals (propose & agree) | Both alter to starboard (no signal exchange required) |
| Crossing | Signal intent with 1 or 2 blasts; other agrees or disagrees | No maneuvering signal required unless altering |
| Flashing light | Required in addition to sound signal (Rule 34) | Not required |
| Constrained by Draft | Not recognized | Recognized — CBD vessel displays blue cylinder |
| Vessel Traffic Service | VTS rules incorporated in Inland | TSS rules in Rule 10 (different detail) |
| Fishing lights | Blue flash light optional (trawler) | Not an option |
Overtaking is the most tested rule. Any vessel coming from more than 22.5° abaft the beam is overtaking — must keep clear period, regardless of vessel type.
When asked who gives way, immediately apply the Rule 18 hierarchy. NUC → RAM → CBD → Fishing → Sail → Power. Exception: the overtaking rule overrides all.
Many questions specify 'inland waters' or 'international waters.' The rules differ on signals. Inland = whistle-to-whistle agreement. International = just steer right, no mandatory exchange.
Masthead: 225°. Sidelights: 112.5° each. Stern: 135°. All-around: 360°. These come up repeatedly. Commit them.
Stand-on vessel must maintain course and speed initially but MUST take action when collision is imminent. The exam tests this nuance.
Five or more short blasts signal doubt or danger. This is the universal 'I am not sure' signal. Never answer a question where this isn't an option for 'I'm unsure of your intentions.'
90% — the highest passing threshold of all four OUPV exam sections. You must get 45 out of 50 questions correct. The exam is answered entirely from memory: no chart, no reference materials allowed. This section has the highest failure rate.
From highest to lowest: Not Under Command (NUC), Restricted in Ability to Maneuver (RAM), Constrained by Draft (CBD, International only), Engaged in Fishing, Under Sail, Power-driven vessel underway. Seaplanes have the lowest priority and must keep clear of all vessels. A vessel overtaking must keep clear regardless of type.
Key differences: (1) Meeting head-on: both exchange one short blast signals under Inland Rules (whistle-to-whistle agreement); (2) Flashing light signals: Inland Rules require a flashing light in addition to sound signals for cross-traffic; (3) Constrained by Draft: only applies under International Rules; (4) Traffic Separation Schemes: specific rules differ; (5) Vessel Traffic Services: Inland Rules have more VTS requirements.
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