By a backflip, I think you mean a tantrum. For sure, go ahead and try one. It's not a difficult trick, and you really don't need that much air to get the board under you. Plus, it's not a trick where you're really going to eat you don't stick it, so just throw it.
It might help to put a little extra weight in the boat, and make sure you throw it late, or else you'll get tripped in the trough (flip too fast with little or no air).