Description

Non Volatile Memory (NVM) is the name given to the ‘flash’ RAM found in many items of solid state avionic equipment fitted to modern aircraft. ‘Non Volatile’ means that, subject to memory capacity, stored data is retained when electrical power is removed. NVM is most often included in a design to aid fault identification and rectification by the provision of a history of recorded fault signals. In a few specific cases where it is used in alerting equipment, it has been envisaged from the outset that such a history might also be of operational use by additionally recording alert activations - Airborne Collision Avoidance System (ACAS) and GPWS/TAWS are the main examples of this and the most likely to be routinely used as data sources for aircraft operators rather than just investigation agencies.