VTVL

Building on the decades of development, SpaceX utilised the VTVL concept for its flagship Falcon 9 first stage, which has delivered over three hundred successful powered landings so far.

After the success of the DC-X prototype, the concept was developed substantially with small rockets after 2000, in part due to incentive prize competitions like the Lunar Lander Challenge.

In 2013, after the failure of stage recovery with parachutes, SpaceX demonstrated vertical landing on a Falcon 9 prototype after climbing 744 meters in the air.

[1] Later, Blue Origin (New Shepard) and SpaceX (Falcon 9), both demonstrated recovery of launch vehicles after return to the launch site (RTLS) operations, with Blue Origin's New Shepard booster rocket making the first successful vertical landing on November 23, 2015, following a flight that reached outer space, and SpaceX's Falcon 9 flight 20 marking the first landing of a commercial orbital booster roughly a month later, on December 22, 2015.

It can also be necessary to be able to ignite engines in a variety of conditions potentially including vacuum, hypersonic, supersonic, transonic, and subsonic.

The main benefit of the technology is seen in the potential for substantial reductions in space flight costs as a result of being able to reuse rockets after successful VTVL landings.

This view was sufficiently ingrained in popular culture that in 1993, following a successful low-altitude test flight of a prototype rocket, a writer opined: "The DC-X launched vertically, hovered in mid-air ...