Dair properties

[Metroid475]

At what point does Mario hit the opponent up during his Dair? Also, does Mario fall faster during his Dair, because sometimes I'm able to do the Dair above my opponent hit them and then hit the ground right before them and add in an up smash. Can someone please tell me how im not popping them up with the Dair?

 

[???????]

Last hit of the Dair hits opponents up dealing 7% damage; the previous hits deal 1% damage totaling up to 12% damage. Dair is momentum based like all aerials and you probably are missing the last hit because you aren't DIing while using it to make sure the opponent stays trapped inside it until the last hit.