Altitude is a 2D side-scrolling airplane shooter game created by Erik Measure and Karl Sabo.
Website: http://altitudegame.com/
PET & SFS: https://copy.com/AJdSgkAOHejT
SFS works just great but if you prefer the PET version, you will have to restart your computer after installation in order to "read" the category and place the icon in the menu ("fixmenus" won't work, don't know why!
).Have fun!!