Menyelek's Flying Wagons

The Ethiopian epic Kebra Nagast tells of "flying wagons" used by Menyelek (or Menelik), the son of King Solomon and the Queen of Sheba. Menyelek escapes with the stolen Ark of the Covenant: "...having loaded their wagons none of them travelled on the ground, but in wagons that were suspended in the air; and they were swifter than the eagles that are in the sky, and all their baggage travelled with them in wagons above the winds." So what are these "flying wagons"?