contrivance vs flight recorder

contrivance

noun
  • A (mechanical) device to perform a certain task. 

  • Something overly artful or artificial. 

  • A means, such as an elaborate plan or strategy, to accomplish a certain objective. 

flight recorder

noun
  • A device which records data that would be of use in investigating the cause of an aircraft accident; usually in pairs, consisting of a flight data recorder and a cockpit voice recorder. 

How often have the words contrivance and flight recorder occurred in a corpus of books? (source: Google Ngram Viewer )