pilotage vs voyage

pilotage

noun
  • The use of landmarks to guide a vessel or aircraft to its destination. 

  • The occupation of a pilot. 

  • The fee paid to a pilot. 

voyage

noun
  • A long journey, especially by ship. 

verb
  • To go on a long journey. 

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