It happened either when I was in Hong Kong airport, waiting for a transfer on to Kaohsiung (coming from Vancouver), or in the air between Hong Kong and Kaohsiung.
People were talking about it in Chinese in the minivan taxi between Kaohsiung and Tainan. I managed to gather that a plane had hit a building in New York, but assumed it was just a minor incident. Of course I learned very differently when I got home.
Now I’m wondering how much news I actually managed to follow that week. I don’t think I had TV, and I may have only had internet access at work. I mostly followed the news just with the weekly Economist. I probably figured out what was going on by calling my parents. Likely with a calling card? Were we still using those for long-distance calls in 2001?