$ PRODUCT DELETE RECOVERY_DATA /OLDEST=2

      The command in this example deletes the two oldest recovery
      data sets starting with the one that was created first,
      followed by next oldest recovery data set. If, for example,
      three patch recovery data sets are on the system disk, you
      still have one set preserved after this operation completes.

      Remember that once a patch recovery data set is deleted, you
      cannot uninstall the patch kit associated with the deleted
      recovery data. The installed patch kits, however, are not
      affected by this action.