Europe's space engineers want to put wings on Ariane rockets

Western Europe is set to take a leaf from the book of space engineers in the United States and develop a winged space vehicle. Like the shuttle, the hardware on the drawing boards in Europe would return to Earth after jettisoning a load such as a satellite into space.

The design, under consideration at the 11-nation European Space Agency (ESA) in Paris, is a variation on the agency's successful Ariane rocket, a conventional expendable booster. All parts of the Ariane are destroyed in taking its payload aloft.

As a way to cut costs, space agency engineers are mulling whether to build a new version of the rocket with wings on the first stage. The second stage of the vehicle, which fires after the first has run out of fuel, would be expended in the normal way.

In the design, the winged section would separate after its job was finished. Instead of burning up in the atmosphre, it would fire small, air-breathing turbo jets, allowing it to behave like an airplane and make a safe return to earth.

If the European Space Agency approves the plan, the winged stage would probably land on a runway that would be constructed at the Ariane launch pad in French Guiana.

The space agency has just released a study done by a consortium of European aerospace firms including Aerospatiale of France, Germany's MBB, and Britain's GEC. Engineers working on the study want a decision within the next year or so on whether to go ahead.

Even if development starts in this time frame, the winged Ariane would not be ready until the mid 1990s. But the space agency's engineers want agreement on the plan because they feel expendable rockets will eventually lose out to space planes such as the shuttle on the grounds of costs.

The first stage of the partly reusable Ariane would have a cryogenic engine. This is a particularly powerful thrusting device using liquid hydrogen and liquid oxygen as fuels.

Space agency planners say developing the winged rocket would be more costly than constructing a more powerful version of an ordinary, expendable launcher. Such a vehicle is also under study as an alternative to the returnable spacecraft. The costs work out at $2.3 billion as against $1.8 billion.

Because launch expenses with the recoverable launch-er are $33 million as opposed to $52 million, the ESA says it would pay for itself after about 25 flights.