Survivability
From Kerbal Space Program Wiki
Survivability is the fifth node on the technology tree, the third and final of the stage 3 nodes. It costs 15 Science and adds three new parts to the game. The focus of this tech node is making landings easier by adding the first landing struts, an alternative parachute option and a compact rocket engine suitable for powered descent.
Required Research
Available Research
This node unlocks two new nodes on the tree: