SESKStuff Everyone Should Know
SESK: Stuff Everyone Should Know · sesk.info/boat-sailboat-running-lights

A sailboat moving under sail alone at night shows which lights?

Sidelights and a sternlight.

  1. Sidelights and a sternlight ✔
  2. A masthead light and a sternlight
  3. One red all-round light

Why: Inland Rule 25 says a sailing vessel underway shows sidelights and a sternlight. Unlike a power-driven vessel under Rule 23, it shows no white masthead light.

Huh, didn't know that: Sailboats under 20 meters may combine those lights into one lantern at or near the top of the mast.

The dad joke
What did the mermaid wear to math class? An algae-bra.
Like this card?
Play the game

Sources

  1. 33 CFR 83.25 Sailing vessels underway and vessels under oars, Inland Rule 25 (eCFR) https://www.ecfr.gov/current/title-33/section-83.25

Test yourself in the game

Boating & WaterWhen must recreational boats show their navigation lights?Boating & WaterAt night you see only another boat's white sternlight, no red or green. What situation is this?Boating & WaterA sailboat has its sails up but is also running its engine. Under the Navigation Rules, it counts as what?

That's stuff everyone should know.