Definition
The unit of electrical capacitance in the centimeter-gram-second (CGS) electromagnetic system of units. One abfarad equals one billion (10^9) farads, the standard unit of capacitance used in modern electrical work.
Plain English
A very large, old-style unit used to measure how much electrical charge a component can store. It is rarely used today; the farad is the standard unit instead.
Context Anchor
Seen mainly in older electrical theory references or maintenance study material, not on normal flight instruments or cockpit checklists.
Derivation
The prefix 'ab-' comes from 'absolute,' referring to the absolute electromagnetic system of units once used in physics. Combined with 'farad' (named after Michael Faraday), it identifies the CGS-system version of the farad.
Why Pilots Care
A pilot is unlikely to use this unit in flight, but recognizing it prevents confusion when reading older aircraft electrical or maintenance material.
Intuition Check
Do not read abfarad as just another spelling of farad. It is an older, different-sized unit; one abfarad equals one billion farads.
Example Sentence 1
The older textbook listed capacitance values in abfarads, which the technician converted to farads before comparing them to the component spec sheet.
Example Sentence 2
Technicians converted the abfarad figure to farads to check the replacement part.