Before the FAA reforms its written knowledge exams, hark back to simpler times and identify these obstruction-to-visibility abbreviations: HZ, FU, PY, SA.


Haze, fumes, dust, sand


Freezing haze, smoke, spray, snow showers


Haze, frost, spray, sand


Haze, smoke, spray, sand

If you enjoyed taking this interactive quiz and would like to see more like it, go to the AVweb Brainteaser page. And if you thought it was unfair, confusing, or a waste of time, we'd like you to tell us that, too. And if you have an idea for a subject that you think would make a good future Brainteaser quiz, be sure to let us know.