Minimum Operational Performance Specifications

It is abbreviated as MOPS.

MOPS are a set of minimum standards and requirements that aviation equipment or systems must meet to operate effectively and safely in real flight conditions. Manufacturers need to build their products to meet these minimum specifications to ensure that the equipment will perform reliably and accurately in airports, airspace, and various flight situations.

For example, if an aircraft navigation GPS system is installed, MOPS defines how accurate, stable, and responsive the system needs to be to be safely used during flight operations.