THE FLIGHT to freedom on a hot-air balloon earlier this month by two East German families may well tempt others in that country to attempt to repeat that airborne escape to West Germany.

The balloon on which the two couples and their four children made their flight westward was constructed from curtains and bed sheets and it was fueled by propane from four cylinders. A previous attempt by the same group failed when the gas ran out before they made it across the border.

Balloon flights across European frontiers have precedents going back to 1785, when the first successful -- and peaceful -- flight was made from England to France.

Escape by balloon had its finest hour during the winter of 1970-71 when Paris was besieged by Germany. A total of 66 balloons was dispatched from the city, carrying not only their 66 pilots (61 of whom had never flown before) but 110 passengers, 2.5 million letters (weighing almost a ton) and 400 pigeons.

The pigeons suffered greatly on their return journey, since the besiegers learned to shoot them down, but the survivors among them brought messages and considerable comfort to the Parisians.

Spies also have made use of balloons, even in recent years. Drifting with the wind by night beneath a black balloon with no metal parts is very inconspicuous, both to the human eye and to radar.

When the spy has landed, the balloon will take off again as soon as the passenger steps out of it. It will return to earth later elsewhere, showing that someone has landed somewhere, but that is all. It is not like the discovery of a parachute, which provides a firm starting point for the pursuers to begin their chase.