Spacex is increasing its launch rate while also making two substantial improvements to its Falcon 9 launch system. The first, recoverability, has gotten the most attention. SpaceX has now landed three of its Falcon 9 boosters on an autonomous drone ship and one on land. Another land-based try is forthcoming—about eight or nine minutes after Monday morning's launch, the first stage of the Falcon 9 will fly back to a landing zone near Cape Canaveral.
The second improvement, using super-cooled liquid rocket fuel, also represents a significant advance. In December 2015, the company debuted its Falcon 9 Full Thrust vehicle, an upgrade from the Falcon 9 v1.1 that included a number of improvements. Perhaps most notable was its use of supercooled liquid oxygen and kerosene fuels. Because colder liquids can be compressed, more of these fuels can be loaded into the Falcon 9's tank. Although it initially led to some difficulties during the fueling process and launch aborts, SpaceX appears to have mastered loading these colder fuels onto the rocket.
The result is a 30-percent gain in power and the ability to launch considerably more mass to low-Earth orbit—22.8 tons now compared to 13.2 with the older version of the rocket. This also means that if you're launching a payload that weighs less than that into space, you've got plenty of fuel left over to stick a first stage landing back on Earth.
SOURCE- Ars Techica