Definition
The unit of magnetomotive force in the centimeter-gram-second (CGS) electromagnetic system. One gilbert is the magnetomotive force required to produce a magnetic flux of one maxwell through a magnetic circuit having a reluctance of one unit.
Plain English
A unit used to measure the magnetic 'push' that drives magnetic field lines through a circuit, similar to how voltage drives current through an electrical circuit.
Context Anchor
Seen in older aircraft electricity, magnetism, generator, motor, and magneto discussions; modern material more often uses ampere-turns.
Derivation
Named after William Gilbert (1544–1603), an English physician and physicist who was one of the first to study magnetism scientifically. The unit honors his foundational work on magnets and the Earth's magnetic field.
Why Pilots Care
Pilots rarely use this unit directly, but it underlies the operation of magnetos, electrical generators, and many cockpit instruments that depend on magnetic fields. Recognizing the term helps when reading maintenance and theory references.
Analogy
Think of the gilbert as the 'voltage' of a magnetic circuit — it's the force that pushes magnetic flux through the circuit, just as voltage pushes electrical current through a wire.
Grounding Statement
When current flows through a coil around a metal core, a gilbert is one way to measure the magnetic push that tries to magnetize that core.
Example Sentence 1
The strength of the magnetic field in the magneto's coil can be expressed in gilberts of magnetomotive force.
Example Sentence 2
Maintenance manuals from the 1950s sometimes listed coil strength in gilberts instead of ampere-turns.