LOB (line of bearing)
A line of bearing (LOB) is a straight line that is used in navigation and surveying to determine the location of an object or a point of interest. It is a critical component of various applications such as marine navigation, air traffic control, and military operations. A line of bearing is typically established by taking two or more measurements of the direction of an object or point from different locations, which are then used to calculate the line of bearing.
LOBs are often used to determine the direction of an object or point relative to a fixed reference point, such as a navigational beacon or a survey station. This can be accomplished using various tools and techniques, such as compasses, radio direction finders, and GPS devices. LOBs are typically represented as straight lines on a map or chart, and can be used to plot a course or navigate to a destination.
In this article, we will explore the concept of line of bearing in more detail, including its definition, types, and applications.
Definition of Line of Bearing
A line of bearing is defined as a straight line that passes through two or more points and indicates the direction of an object or point of interest relative to a fixed reference point. The reference point is typically a navigational beacon or survey station that is used to establish a known position.
LOBs are typically measured using various instruments and techniques, including compasses, radio direction finders, and GPS devices. The accuracy of the LOB measurement depends on the precision of the measurement instrument and the technique used to establish the reference point.
Types of Line of Bearing
There are two main types of line of bearing: magnetic and true.
Magnetic line of bearing (MLB) refers to the direction of an object or point relative to magnetic north. It is measured using a magnetic compass, which is calibrated to compensate for magnetic declination, or the difference between true north and magnetic north. Magnetic declination varies depending on the location on Earth and can be determined using charts or GPS devices.
True line of bearing (TLB) refers to the direction of an object or point relative to true north. It is measured using a gyrocompass or a GPS device that is calibrated to true north. Unlike magnetic north, true north is a fixed reference point that is located at the North Pole.
Applications of Line of Bearing
LOBs have various applications in navigation, surveying, and military operations. Some of the key applications of LOBs are:
- Marine navigation: LOBs are used in marine navigation to determine the direction of a ship or boat relative to a navigational beacon or landmark. This information is used to plot a course and navigate safely to a destination.
- Air traffic control: LOBs are used in air traffic control to determine the direction of an aircraft relative to a navigational beacon or radar station. This information is used to guide the aircraft to a safe landing or to avoid collisions with other aircraft.
- Surveying: LOBs are used in surveying to establish the location of survey points relative to a fixed reference point. This information is used to create accurate maps and charts.
- Military operations: LOBs are used in military operations to determine the location of enemy forces and to plan tactical maneuvers. This information is critical for successful military operations.
In addition to these applications, LOBs are also used in various other fields, such as geology, wildlife tracking, and search and rescue operations.
Conclusion
Line of bearing is a critical concept in navigation and surveying. It is used to determine the direction of an object or point of interest relative to a fixed reference point, such as a navigational beacon or survey station. LOBs are typically measured using various instruments and techniques, such as compasses, radio direction finders, and GPS devices. They have various applications in marine navigation, air traffic control, surveying, military operations, geology, wildlife tracking, and search and rescue operations.