**2.1 Space applications**

The space applications scenario belongs to space activities related to in-orbit activities and space exploration. Usually, hypersonic vehicles of this class are referred to as space planes and are unpowered and very blunt to slow down as much as possible while controlling the aerodynamic heating during re-entry or atmospheric entry (i.e. flying on other planets with atmosphere like Mars). So far, only three space planes have ever successfully flown: NASA's Space Shuttle, Boeing's X-37B, and the Soviet Buran, as shown in **Figure 2**.

Further, other countries are developing their own space plane like China and Europe. Few information about research developments of China is available due to reasons of confidentiality and secrecy. But, European Space Agency (ESA) is

**Figure 2.** *US shuttle orbiter, soviet buran, and US X-37. Not to scale. Courtesy of Giuseppe De Chiara.*

*Introductory Chapter: The Challenge to Fly Faster and Higher DOI: http://dx.doi.org/10.5772/intechopen.103729*

**Figure 3.** *Space rider. Courtesy of ESA.*

**Figure 4.** *SNC dream chaser. Courtesy of Giuseppe De Chiara.*

expected to fly its own in-development space plane, namely Space Rider, whom maiden flight is expected in 2023, see **Figure 3** [2, 3].

More mature and nearly ready to flight is the two-stage space plane, namely Dream Chaser, under development by the Sierra Nevada Corporation (SNC) [4]. This space plane will support cargo resupply missions to and from the International Space Station (ISS), by 2022, and astronauts transfer by 2025, as well. With the Dream Chaser, the US will have again a commercial vehicle return from the ISS to a runway landing for the first time since the retirement of the NASA's space shuttle program (**Figure 4**).
