Originally Posted by mugaliens

I read CNN's Phoenix Mission article with interest, but balked at the following:

""I love airbags," said Weiler. "We got three success stories with airbags, but you don't invent science by continuing to do what you know how to do."

Engineers did not use airbags on Phoenix because the lander is simply too big and heavy for them to work properly. And NASA will have to figure out how to land reliably with thrusters and landing legs in order to fly even larger spacecraft in the future."

The Russians have been using parachuted palat deliver system for years whose rate of descent during it's final few feet is arrested. They simply hang a weight "depth guage" over the side, and when it touches the ground, the rockets fire, slowing the palat to a near stop by the time it touches down.

Simple side-looking doppler radar combined with a steerable parachute can easily halt sideways movement. Finally, a laser ground mapping device can be used in the parachute descent phase to find a rockless and level piece of land on which to touchdown.

This isn't rocket science - these applications have been around for years!