Keep your Brainteaser Decoder Ring™ handy and refer to this partial NOTAM:
Ailerona IA [IA66]: February NOTAM #45 Aerodrome airport WDI for runway 23 light OUT of SERVICE
The Runway 23 WDI is OUT of SERVICE. But you don't need to push the Ercoupe back into the hangar, because you know that WDI means:
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.