爆睡

ばくすい
Bakusui
Crashed; fast asleep (right away)

*It's interesting how we say the same in Chinese these days...

深夜の飛行機で一睡もできなかったらしく帰宅後爆睡。
Shinya no hikooki de issui mo dekinakatta rashiku kitaku ato bakusui.
It seems I was unable to sleep on the late night plane (but) I crashed upon returning home.