Definition
A unit of electrical capacitance equal to one-trillionth (10⁻¹²) of a farad. Picofarads are used to measure very small capacitor values commonly found in radio, navigation, and avionics circuits. The symbol is pF.
Plain English
A very tiny measure of how much electrical charge a capacitor can hold. One picofarad is one-trillionth of a farad, so the number is small because the farad itself is a very large unit.
Context Anchor
Seen in aircraft electrical, radio, antenna, and avionics maintenance information when small capacitors or circuit values are listed.
Derivation
The prefix pico- comes from the Italian piccolo, meaning 'small,' and in the metric system it means one-trillionth. Farad is named after British scientist Michael Faraday, who pioneered the study of electricity. So picofarad literally means 'a tiny Faraday-unit of capacitance.'
Why Pilots Care
Pilots rarely measure picofarads directly, but the term shows up when reading avionics documentation or troubleshooting radio gear with a technician. Knowing the unit prevents confusion when discussing component values.
Analogy
If a farad were an extremely large container for electrical charge, a picofarad would be a container so small it is used for fine electronic adjustments rather than large power storage.
Intuition Check
Do not read picofarad as a special aviation device. It is a measurement unit for a very small amount of electrical charge storage.
Example Sentence 1
The radio's tuning circuit used a capacitor rated at 47 picofarads.
Example Sentence 2
During component testing the technician verified the picofarad value printed on the part.