head-on vs plain sailing

head-on

adj
  • Direct, abrupt, blunt or unequivocal; not prevaricating. 

  • Of a collision, from the front or in the direction of motion. 

noun
  • A collision from the front. 

adv
  • With the front of a vehicle. 

  • With direct confrontation. 

plain sailing

adj
  • simple, straightforward, or easy 

noun
  • The navigation of waters free from hazards or unfavourable winds. 

  • Something that is simple, straightforward, or easy; something that offers no troubles or difficulties. 

How often have the words head-on and plain sailing occurred in a corpus of books? (source: Google Ngram Viewer )