Definition
The maximum amount of information that an avionics database, navigation receiver, or flight management system can hold at one time. In RNAV and GPS equipment, this capacity sets a practical limit on how many navigation data records — such as airports, waypoints, airways, approaches, and departure or arrival procedures — can be loaded onto the unit for a given coverage area or update cycle.
Plain English
How much information the box in the panel can store. If the unit only has room for a certain amount of navigation data, you may not be able to load every airport and procedure in the world at once — you load what you need for where you're flying.
Context Anchor
Seen when checking, loading, or using an aircraft navigation database for instrument flying.
Derivation
Data comes from a Latin word meaning “things given.” Capacity comes from a Latin word meaning “to take in or hold.” Together, the phrase points to how much given information a system can hold.
Why Pilots Care
Exceeding storage capacity can result in incomplete navigation databases, forcing pilots to rely on backup methods or limiting route options.
Analogy
It is like the storage space on a phone. If the phone is full, it cannot hold more apps or photos; if the aircraft system is full, it may not hold all the aviation data the pilot expects.
Intuition Check
Do not assume data storage capacity tells you whether the information is correct or up to date. It only tells you how much information the system can hold.
Example Sentence 1
Because of the GPS unit's data storage capacity, the pilot subscribed only to the North American coverage area rather than the worldwide database.
Example Sentence 2
Due to limited data storage capacity, older procedures had to be removed to accommodate new instrument approaches.