Why are spaceships launched vertically, as opposed to along a runway like an airplane

A.� Both airplanes and spaceships need lift to get them off the ground but they achieve this in different ways, which accounts for their different launch positions.

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An airplane uses its wings for take off. The wings are designed so that when a certain speed is achieved the air passing below them has a higher pressure that that flowing above them. The higher pressure pushes the wings, and the airplane they're attached to, off the ground.

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However a spaceship doesn't have wings and so it relies entirely on the thrust provided by is engines to achieve lift off. Since the spaceship needs to travel vertically, at least to start with, it's more economical to take off vertically so that all the backwards thrust created by the engines, by expelling hot gases through nozzles, propels it in a forward, or vertical direction.

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Q.� Why is it more economical for a spaceship to travel vertically at take off

A.� Our planet has an atmosphere, fortunately for us, but it does cause friction when spaceships take off, slowing it down. By taking off vertically the amount of drag created by our atmosphere is minimised.

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Q.� Why don't spaceships have wings

A.� Because where they're going the air is either too thin or non-existent to lift anything.

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Q.� I'm sure the space shuttle has wings

A.� It does, but they're very small in comparison with those of an airplane and are only used for landing purposes.

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Q.� So we could scrap using planes and just fly from country to country on spacships

A.� Theoretically yes, practically no, because spaceships rely entirely on engine thrust rather than planes that rely on air speed to fly. Space travel consumes huge amounts of fuel and is therefore rather pricey.

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by Lisa Cardy