In 2001, the Israeli airline El Al rejected a request to allow certain passengers to zip themselves into body bags when their planes passed over a cemetery.
Under Ultra-Orthodox Jewish law, Jews descended from the biblical priests must not enter a cemetery.
The request to El Al came after a recent interpretation extended that ruling to cover the airspace above cemeteries too.
If they were in plastic body bags, however, they would no longer be deemed unclean if they flew over a cemetery. The religious authorities dropped the idea when told it was not safe to zip yourself inside a body bag. They adopted instead an alternative solution of taking night flights from Tel Aviv, when noise pollution regulations forced them to alter their usual flight path to one that avoided cemeteries.