Rule 29 — Pilot Vessel Lights

TL;DR — A vessel engaged on pilotage duty displays two all-round lights in a vertical line at or near the masthead: upper white, lower red. When underway she adds sidelights and a sternlight; when at anchor she adds anchor lights or shapes instead. A pilot vessel not on pilotage duty shows only the lights appropriate to her length and type.

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What the Rule Says

The identifying signal: two all-round lights, upper white, lower red

The single most testable fact about pilot vessels is the masthead signal. Under 33 CFR §83.29, a vessel engaged on pilotage duty shall exhibit, at or near the masthead, two all-round lights in a vertical line, the upper being white and the lower red. 33 CFR §83.29

An all-round light, by definition, shows an unbroken light over an arc of the horizon of 360 degrees. 33 CFR §83.21 These two all-round lights are therefore visible from any direction — they are the pilot vessel's identity signal, not a directional light.

Underway on pilotage duty

When the vessel is underway and engaged on pilotage duty, she exhibits, in addition to the white-over-red all-round pair:

• Sidelights — green to starboard, red to port, each covering 112.5 degrees from right ahead to 22.5 degrees abaft the beam on the respective side 33 CFR §83.21
• A sternlight — white, covering 135 degrees centered on right aft (67.5 degrees each side) 33 CFR §83.21

Note carefully what is not listed: there is no requirement for a masthead steaming light under Rule 29. The white-over-red all-round pair replaces the masthead light that a power-driven vessel would otherwise show under Rule 23. 33 CFR §83.29

At anchor on pilotage duty

When at anchor and engaged on pilotage duty, the vessel exhibits the white-over-red all-round pair plus the anchor light, lights, or shape prescribed in Rule 30 for vessels at anchor. 33 CFR §83.29 She does not add sidelights or a sternlight — those are only required when underway.

Not on pilotage duty

A pilot vessel when not engaged on pilotage duty shall exhibit the lights or shapes prescribed for a vessel of her length. 33 CFR §83.29 In other words, the white-over-red identity signal disappears entirely; she reverts to the standard lights for her size and propulsion type.

Vertical spacing of the two all-round lights

Annex I addresses the physical placement of lights carried in a vertical line. On a vessel of 20 meters or more in length, two lights in a vertical line shall be spaced not less than 1 meter apart, and the lowest of those lights shall be placed at a height of not less than 4 meters above the hull. 33 CFR §84.02 On a vessel of less than 20 meters, the spacing is still not less than 1 meter apart, but the lowest light need only be at a height of not less than 2 meters above the gunwale. 33 CFR §84.02

Visibility ranges

The two all-round lights are white and red all-round lights, so their required visibility ranges follow Rule 22. For a vessel of 50 meters or more: white or red all-round light, 3 miles. 33 CFR §83.22 For a vessel of 12 meters or more but less than 50 meters: 2 miles. 33 CFR §83.22 For a vessel of less than 12 meters: 2 miles. 33 CFR §83.22

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Why It Matters on the Exam

OUPV and Master 100 GT written exams test Rule 29 in several recurring ways:

1. Color and order of the all-round lights. The most common distractor is reversing the colors — placing red on top and white on the bottom. The rule is unambiguous: upper white, lower red. 33 CFR §83.29 Memorize the order as "white on top, red below," just as white is above red in a traffic signal.

2. Underway vs. at anchor light combinations. Exam questions frequently present a scenario and ask which complete set of lights is correct. When underway on pilotage duty, the correct answer is white-over-red all-round pair plus sidelights and sternlight. 33 CFR §83.29 When at anchor on pilotage duty, the correct answer is white-over-red all-round pair plus anchor light(s) or shape — no sidelights, no sternlight. 33 CFR §83.29

3. The "not on pilotage duty" trap. A question may describe a pilot vessel that is transiting between assignments or returning to port without a pilot embarked. In that case, she shows no white-over-red signal — only the lights appropriate to her length. 33 CFR §83.29 Candidates who memorize "pilot vessel = white over red" without the qualifying condition will miss this.

4. No masthead steaming light. Rule 23 requires a power-driven vessel underway to show a masthead light forward. 33 CFR §83.23 A pilot vessel on pilotage duty does not add a Rule 23 masthead light on top of the white-over-red pair. The all-round lights at or near the masthead serve as her identity signal; the rule does not prescribe an additional forward masthead light. 33 CFR §83.29

5. Arc of the identity lights. Because both lights are all-round (360 degrees), they are visible from any bearing — ahead, astern, or abeam. 33 CFR §83.21 This distinguishes them from sidelights (112.5 degrees each) 33 CFR §83.21 and the sternlight (135 degrees). 33 CFR §83.21

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Common Pitfalls

Pitfall 1 — Reversing the colors. Upper white, lower red. Not upper red, lower white. 33 CFR §83.29 This is the single most frequently missed detail on the exam.

Pitfall 2 — Confusing "at or near the masthead" with a masthead light. The white-over-red pair is carried at or near the masthead, but these are all-round lights (360 degrees), not masthead lights (225 degrees). 33 CFR §83.21 A masthead light by definition covers only 225 degrees. 33 CFR §83.21 The pilot vessel's identity lights cover the full horizon.

Pitfall 3 — Adding sidelights and sternlight when at anchor. When at anchor on pilotage duty, the vessel adds anchor lights or shapes, not sidelights and sternlight. Sidelights and sternlight are only added when the vessel is underway. 33 CFR §83.29

Pitfall 4 — Applying pilot vessel lights when not on duty. If the vessel is not engaged on pilotage duty, she shows no special lights at all — only the standard lights for her length and type. 33 CFR §83.29 Do not assume that any vessel labeled "pilot boat" automatically shows white over red.

Pitfall 5 — Forgetting the vertical spacing minimums. Annex I requires the two vertical all-round lights to be spaced not less than 1 meter apart regardless of vessel length. 33 CFR §84.02 The minimum height of the lower light differs by vessel size: 4 meters above the hull for vessels 20 meters or more, 2 meters above the gunwale for vessels less than 20 meters. 33 CFR §84.02

Pitfall 6 — Misapplying visibility ranges. The white and red all-round lights on a pilot vessel are subject to the all-round light visibility requirements of Rule 22, not the masthead light requirements. A vessel under 50 meters must show those all-round lights to a minimum of 2 miles; a vessel 50 meters or more must show them to 3 miles. 33 CFR §83.22

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Quick Check

Q1 — A vessel engaged on pilotage duty is underway. List every light she is required to exhibit.

Two all-round lights in a vertical line at or near the masthead (upper white, lower red), plus sidelights and a sternlight. 33 CFR §83.29

Q2 — What is the color arrangement of the two all-round lights on a pilot vessel on pilotage duty?

Upper white, lower red. 33 CFR §83.29

Q3 — A pilot vessel is at anchor and engaged on pilotage duty. What lights does she show?

The two all-round lights (upper white, lower red) at or near the masthead, plus the anchor light, lights, or shape prescribed by Rule 30. She does not show sidelights or a sternlight while at anchor. 33 CFR §83.29

Q4 — A pilot vessel is returning to port with no pilot embarked and is not on pilotage duty. What lights does she show?

The lights or shapes prescribed for a vessel of her length — no white-over-red all-round lights. 33 CFR §83.29

Q5 — What is the arc of visibility of each of the two all-round lights carried by a pilot vessel on pilotage duty, and what regulation defines "all-round light"?

Each all-round light shows an unbroken light over an arc of the horizon of 360 degrees. 33 CFR §83.21

Q6 — For a pilot vessel of 25 meters in length on pilotage duty, what is the minimum required visibility range for the white all-round light at the masthead?

2 miles. A vessel of 12 meters or more but less than 50 meters must show a white, red, green, or yellow all-round light to a minimum of 2 miles. 33 CFR §83.22

Q7 — Annex I requires the two vertical all-round lights on a pilot vessel of 22 meters to be spaced how far apart, and the lowest light placed at what minimum height?

Not less than 1 meter apart vertically, with the lowest light at a height of not less than 4 meters above the hull. 33 CFR §84.02

Q8 — Does a pilot vessel on pilotage duty also exhibit a forward masthead light as required by Rule 23 for power-driven vessels?

No. Rule 29 prescribes the lights for a vessel engaged on pilotage duty, and it does not require an additional Rule 23 masthead light. The white-over-red all-round pair at or near the masthead constitutes the vessel's identity signal. 33 CFR §83.29