It wasn't the first, even at cruise phase of the flight, nor was the last.<p>You can check a list here: <a href="https://en.wikipedia.org/wiki/Mid-air_collision#List_of_notable_civilian_and_military-civilian_mid-air_collisions" rel="nofollow">https://en.wikipedia.org/wiki/Mid-air_collision#List_of_nota...</a>