acid test vs shakedown

acid test

• A rigorous test or appraisal of the quality or worth of something. 

• In the 1960s, a party based around the use and advocacy of the psychedelic drug LSD ("acid"). 

shakedown

• A trial or test period, especially of a ship or aircraft 

• Extortion, especially through blackmail 

• A thorough search; a frisk 

• An improvised bed. 

• that tests the performance of a ship or aircraft