International Civil Aviation Day has been celebrated since 7 December 1994, the 50th anniversary of the signing the Convention on International Civil Aviation. The day is still celebrated around the world by people in the aviation community like ATC (air traffic control), airport management, and airlines.
This day also celebrates flights like QF32 and US Airways 1549 which were disaster situations but the pilots and crew managed to save the passengers and most of the plane.
The purpose of the day is to recognize the importance of aviation, especially international air travel, to the social and economic development of the world.
Sponsored by the International Civil Aviation Organization, the day celebrates the role of aviation in helping States to cooperate and realize a truly global rapid transit network at the service of all mankind.
P.S. I do know that is is also Pearl Harbor Remembrance Day. I’m just trying to keep it International and celebratory.

This is the official poster for International Civil Aviation Day and was downloaded from the International Civil Aviation Organization website.