I lived in Flagstaff, AZ for 6.5 years - Jan 1975 to Sept 1981. While attending NAU for my MBA degree and for several years afterwards, I was a flight instructor, charter and corporate pilot.
I had the good/great fortune/special opportunity to fly a number of sight-seeing trips through the Grand Canyon back in the day when flying fixed wing aircraft below the South Rim was allowed. Each trip through the Canyon was special!
Hiking the Canyon, North to South is a huge feat! KUDOS to that gentleman!
I never wanted to hike the Canyon; would rather fly!
I envy you for flying in that gorgeous area.