ceiling zero vs zero-zero

ceiling zero

zero-zero

adj
  • Pertaining to the ejection of the occupant of an aircraft from a grounded stationary position (i.e. zero altitude and zero airspeed). 

  • Involving neither of two powers increasing their stockpile of nuclear weapons. 

  • Pertaining to weather conditions of zero ceiling and zero visibility (i.e., opaque cloud all the way down to ground level), or to aircraft operations in such conditions. 

How often have the words ceiling zero and zero-zero occurred in a corpus of books? (source: Google Ngram Viewer )