From FreeSpace Wiki
Special-check Mike K.'s special training sexp. Returns a boolean value. Takes 1 argument as follows: 0: Ship "Freighter 1" is aspect locked by the player 1: Player has fired Interceptor#Weak at Freighter 1 2: Ship "Freighter 1", subsystem "Weapons" is aspect locked by the player 3: Apply 10 points of damage to player's forward shields (action operator) 4: Player's front shields are nearly gone 5: Quickly recharge player's front shields (action operator) 6: Reduce all shield quadrants except front to 0 (action operator) 7: Front shield quadrant is near maximum strength 8: Rear shield quadrant is near maximum strength 9: Reduce left and right shield quadrants to 0 (action operator) 10: Player has fewer than 8 missiles left 11: Player has 8 or more missiles left 12: Player has fewer than 4 missiles left 13: Reduce front shield quadrant to 0 (action operator) 100: Player is out of countermeasures 2000: Training failed
As it can be easily noted, this useful SEXP triggers several kinds of effects used in training missions.