Horntail and the drop bugs?

I don't quite understand it.

The other day, I Ht'd for the first time after 5 years of playing in maplestory servers (Which was one of my goals ) but didn't drop anything (since we were 4 and one dced). By what you are saying, if we enter Ht with 5 people, do we have to wait 30 minutes before we completely kill it, or before the party enters HT? Someone explain clearly ^^'

To the best of my understanding, you have to wait half an hour after Horntail is summoned to kill him to get loot. Additionally, I think there's some stipulation (or at least there was for CHT) that you need a certain number of people alive and in Horntail's room when he dies.