Having terrible difficulties this week !
21d...US soldier has year free on the road to indulge in reckless acts..?O?R?D?
JOYRIDE ? can't parse this.
3d...One of the old Asian species now inhabiting African nations...?N?A...ANNA ( an old Indian coin)
18d...Tend towards less productive director...?E?N
17d...S African runner cut off in dash out of 18..E?A?