A
logbook was originally a book for recording readings from the
chip logA chip log, also called common log, ship log or just log, is a navigation tool used by mariners to estimate the speed of a vessel through water.-Construction:...
, and is used to determine the distance a ship traveled within a certain amount of time. The readings of the log have been recorded in equal times to give the distance traveled with respect to a given start position.
Today's
ship's log has grown to contain many other types of information, and is a record of operational data relating to a
shipSince the end of the age of sail a ship has been any large buoyant marine vessel. Ships are generally distinguished from boats based on size and cargo or passenger capacity. Ships are used on lakes, seas, and rivers for a variety of activities, such as the transport of people or goods, fishing,...
or
submarineA submarine is a watercraft capable of independent operation below the surface of the water. It differs from a submersible, which has more limited underwater capability...
, such as weather conditions, times of routine events and significant incidents,
crewA crew is a body or a class of people who work at a common activity, generally in a structured or hierarchical organization. A location in which a crew works is called a crewyard or a workyard...
complement or what
portA port is a location on a coast or shore containing one or more harbors where ships can dock and transfer people or cargo to or from land....
s were docked at and when. It is essential to traditional navigation, and must be filled in at least daily.
Most National shipping authorities and Admiralties specify that logbooks are kept to provide a record of events, and to help crews navigate should
radioRadio is the transmission of signals through free space by modulation of electromagnetic waves with frequencies below those of visible light. Electromagnetic radiation travels by means of oscillating electromagnetic fields that pass through the air and the vacuum of space...
,
radarRadar is an object-detection system which uses radio waves to determine the range, altitude, direction, or speed of objects. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain. The radar dish or antenna transmits pulses of radio...
or the GPS fail. Examination of the detail in a ship's log is often an important part of the investigative process for official maritime inquiries, in much the same way as a "
black boxA flight data recorder is an electronic device employed to record any instructions sent to any electronic systems on an aircraft. It is a device used to record specific aircraft performance parameters...
" is used on airplanes (see
Mary CelesteThe Mary Celeste was an American brigantine merchant ship famous for having been discovered on 4 December 1872, in the Atlantic Ocean unmanned and apparently abandoned , despite the fact that the weather was fine and her crew had been experienced and able...
). Logbook entries are sometimes of great importance in legal cases involving maritime commercial disputes.
The term
logbook has spread to a wide variety of other endeavors, and logbooks are widely used for e.g. complex machines like nuclear plants or particle accelerators where one is more and more using a computer based
electronic logbookAn electronic logbook is a computer based software for recording states, events or simply conditions used for complex machines like aircraft, nuclear plants, particle accelerators, various areas on board ships replacing paper based logbooks, etc....
. In military terms, a logbook is a series of official and legally binding documents. Each document (usually arranged by date) is marked with the time of an event or action of significance.
Commercial ships and Naval vessels often keep a "rough log," - or "scrap log," - a preliminary draft of the ship's course, speed, location, and other data, which is then transcribed as the "smooth log," - or "official log" - the final version of the ship's record. Changes may be made to the rough log but the smooth log is considered permanent and no erasures are permitted. Alterations or corrections in an official logbook must be initialled by the authorised keeper of the logbook and the original data entries which have been cancelled or corrected must remain legible.
Use in fiction
- The Hornblower
Hornblower is the umbrella title of a series of television drama programmes based on C. S. Forester's novels about the fictional character Horatio Hornblower, a Royal Naval officer during the French Revolutionary Wars and the Napoleonic Wars....
series mentions logs to explain plot development, or to make the story more realistic.
- Reading a log can make a dramatic explanation of a mysterious disaster in most sci-fi.
- In Star Trek
Star Trek is an American science fiction entertainment franchise created by Gene Roddenberry. The core of Star Trek is its six television series: The Original Series, The Animated Series, The Next Generation, Deep Space Nine, Voyager, and Enterprise...
the Captain's log, a form of ship's log, is used to fill in the audience as to the events in progress, and acts as a more realistic form of soliloquyA soliloquy is a device often used in drama whereby a character relates his or her thoughts and feelings to him/herself and to the audience without addressing any of the other characters, and is delivered often when they are alone or think they are alone. Soliloquy is distinct from monologue and...
.
Alternative connotation
A
logbook is also a colloquial term for the V5C car registration document in the
UKThe United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
.
In the
fishing industryThe fishing industry includes any industry or activity concerned with taking, culturing, processing, preserving, storing, transporting, marketing or selling fish or fish products....
, a
logbook is used to record catch data as part of the fisheries regulations. It is then submitted to the fishing authorities of the vessel's flag state.
For
Amateur radioAmateur radio is the use of designated radio frequency spectrum for purposes of private recreation, non-commercial exchange of messages, wireless experimentation, self-training, and emergency communication...
the logbook is where the hams register their QSO and radio activity. There are several programs to help radio operators in the management of their logbook.
Pilots of aircraft must maintain a logbook (as per FAR part 61.51. in the USA, JAR-OPS 1.970 for Nations enrolled in the JAA) Pilots must log flight time used to meet the requirements for a certificate or rating, and for currency purposes.
In
scuba divingScuba diving is a form of underwater diving in which a diver uses a scuba set to breathe underwater....
to log a divers dives. The logbook documents the experience of a diver.
See also
- Binnacle
A binnacle is a waist-high case or stand on the deck of a ship, generally mounted in front of the helmsman, in which navigational instruments are placed for easy and quick reference as well as to protect the delicate instruments. Its traditional purpose was to hold the ship's magnetic compass,...
- CLIWOC
The Climatological database for the world's oceans was a research project to convert ships' logbooks into a computerised database. It was funded by the European Union, and the bulk of the work was done between 2001 and 2003...
(climatological database for the world's oceans)
- Navigation
Navigation is the process of monitoring and controlling the movement of a craft or vehicle from one place to another. It is also the term of art used for the specialized knowledge used by navigators to perform navigation tasks...
External links