What is Pitot Speed Log?

Pitot Log is a type of Speed Log which is used to measure the speed of a ship.

Features of Pitot Speed Log:
  • Pitot log works on sensing of pressure difference.
  • Has retractable tube which has two pipes, one of these is facing forward (the dynamic tube) the other is facing down (the static tube).
  • When there is no movement across the tubes, pressure exerted on both tubes will be the same. (when relative speed of water is ZERO).
  • When there is movement of water across the face of the tubes, the pressure in the dynamic tube will be greater than in the static tube.
  • This difference is converted into an EMF and shown on the speed indicator.
  • Greater the speed of water, greater the pressure difference, greater emf, greater the displayed speed.