Judah wrote in message
Where would I find out the total number of airplanes owned by all of the
airlines worldwide?

The FAA estimated that in 2002 there were 5,156 passenger jet
aircraft, 976 regional jets, 1,034 cargo jet aircraft, and 2,521
commuter (prop and jet) aircraft in the U.S. That's a total of 9,687
aircraft.

Source: FAA Aerospace Forecasts, FY 2003-2014, Tables 20, 21, and 27.