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Toby Speight
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Well, firstly, there's generally no need, given that any reasonable navigator carries a compass, thereby allowing the direction to be determined. With two or more known lights in sight, a simple resection gives the vessel's position.

However, some lights are set up to give rapid indication of whether the vessel is on the right heading in one of two ways:

  • Leading lights which are in the same direction when approaching from the correct direction (e.g. into a harbour), and
  • sector lights which show different colours according to direction, allowing vessels to correct a course which would intercept an obstacle.

No timing is required for either of these to work.


The presupposition to the question is probably that VOR solves a problem for aircraft navigation, so there ought to be a solution to the same problem in marine navigation.

The flaw in that reasoning is that there is no marine equivalent problem: radio receivers are almost omnidirectional (by design), but light receivers (our eyes) are very directional. So, the problem that VOR solves is one that simply doesn't exist for lighthouses.

Well, firstly, there's generally no need, given that any reasonable navigator carries a compass, thereby allowing the direction to be determined. With two or more known lights in sight, a simple resection gives the vessel's position.

However, some lights are set up to give rapid indication of whether the vessel is on the right heading in one of two ways:

  • Leading lights which are in the same direction when approaching from the correct direction (e.g. into a harbour), and
  • sector lights which show different colours according to direction, allowing vessels to correct a course which would intercept an obstacle.

No timing is required for either of these to work.

Well, firstly, there's generally no need, given that any reasonable navigator carries a compass, thereby allowing the direction to be determined. With two or more known lights in sight, a simple resection gives the vessel's position.

However, some lights are set up to give rapid indication of whether the vessel is on the right heading in one of two ways:

  • Leading lights which are in the same direction when approaching from the correct direction (e.g. into a harbour), and
  • sector lights which show different colours according to direction, allowing vessels to correct a course which would intercept an obstacle.

No timing is required for either of these to work.


The presupposition to the question is probably that VOR solves a problem for aircraft navigation, so there ought to be a solution to the same problem in marine navigation.

The flaw in that reasoning is that there is no marine equivalent problem: radio receivers are almost omnidirectional (by design), but light receivers (our eyes) are very directional. So, the problem that VOR solves is one that simply doesn't exist for lighthouses.

Source Link
Toby Speight
  • 4.8k
  • 23
  • 43

Well, firstly, there's generally no need, given that any reasonable navigator carries a compass, thereby allowing the direction to be determined. With two or more known lights in sight, a simple resection gives the vessel's position.

However, some lights are set up to give rapid indication of whether the vessel is on the right heading in one of two ways:

  • Leading lights which are in the same direction when approaching from the correct direction (e.g. into a harbour), and
  • sector lights which show different colours according to direction, allowing vessels to correct a course which would intercept an obstacle.

No timing is required for either of these to work.