MECO (Main Engine Cut Off)
The time at which the main engines of the shuttle, are automatically controlled to stop firing. MECO typically involves a sequence of events, including throttling back the engines before actual cutoff. The MECO sequence for the Space Shuttle begins about 10 seconds before cutoff. About three seconds later, the Space Shuttle Main Engines (SSMEs) are commanded to begin throttling back at intervals of 10% thrust per second until they reach a thrust of 65% of rated power, called minimum power. Minimum power is maintained for just under seven seconds, then the SSMEs shut down.