:: descent to the planet
During the descent phase the heat shield brakes the lander from its interplanetary velocity, energy being lost by frictional heating. Firing the parachute deployment device (PDD) through a patch in the back cover, deploys a pilot chute whose role is to divide the space craft into two sections whilst pulling the main chute from its stowed position.
Pyrotechnic bolts explode to drop the heat shield. The gas-bags are inflated by a gas generator at 200m above the surface (as detected by a radar altimeter) and on first contact the device releases the main parachute so that the lander can bounce away from underneath the canopy. When the whole package comes to rest, a system of laces holding the three gas-bags onto the lander is cut allowing them to reform and roll away, dropping Beagle 2 onto the surface. Irrespective of which way up it falls a hinge will open the clam shell to start the science phase of the mission.