What uncommon characteristic do the following five five-letter words have in common?

ALOFT   CHART   HUMAN   PAEAN   WARTY

Bonus: If you truly have a bit for the uncommon, can you identify any other five-letter English words that share this property?

Perhaps this puzzle's difficulty was set too low. (I had planned on increasing it, but  I saw it already had been posted).

The title of the puzzle gives the hint to the property I am seeking.  None of the nine English words that I found with this property have neither an i nor an s, though I would not discount those letters in non-English words that share the property.