N.A.S.E., Known as Nicholas Aeronautics Servicable Experiment, was designed to be fully reusable. This program allowed N.S.P. to understand the benefits of fully reusable spaceplane, along with how to make them.
The first mission of the N.A.S.E. Program was to test if the spaceplane was able to fly aerodynamically and land without issues. It succeeded in both areas, which allowed for the plane to be used in future launches.
The second launch of the N.A.S.E. Program was to test if the vessel could achieve orbit while being fully reusable. It passed this test with flying colors, allowing for roughly 2000 m/s^2 in fuel after orbit.
The Third Launch of the N.A.S.E. was to dock to the U.S.S., a space station module that needed supplies. Luckily, the N.A.S.E. passed all regulations, and was sent up to dock. It was able to dock successfuly.
After the N.A.S.E. proved itself to be a success, N.S.P. decided that it would be used primarily as a cargo vessel and a satellite deployment vessel. Thus, supplies were sent to space, and the craft later returned to Kerbin.
