What Are Space Planes?

These hybrid aircraft provide reusable means to access space. 

Written by Brooke Becher
Published on Apr. 22, 2024
What Are Space Planes?
Image: Shutterstock

A space plane combines elements of an airplane and a spacecraft into one high-flying vessel. Like a commercial jetliner, it’s designed to glide in the sky, and like a rocket ship, it can maneuver through outer space — including orbit entry — without a problem. Space planes typically feature wings, rocket engines and heat-resistant coating, which protects the vehicle during its return journey.

What Is a Space Plane?

A space plane is an aircraft capable of both space and atmospheric flight. It’s built to withstand multiple missions traveling from the Earth’s surface into outer space and back, landing intact on a conventional runway.

A defining characteristic of space planes is that they are built to withstand multiple trips, for “re-use,” and remain intact after landing. Typically, they launch vertically with the help of a rocket or mothership, and autonomously touch down for a conventional runway landing.

Despite their late-1950s debut, space planes are still considered an emerging technology. To date, only six space planes have successfully flown to outer space and re-entered Earth’s atmosphere with safe landing.

Space planes have always been about expanding access to space. They’ve been used to conduct in-orbit experiments, ferry cargo and provide infrastructure support. More recently, as the private sector overtakes government-funded projects, space planes have become a choice vehicle for space tourism.

Below is a list of space planes — retired, active and in progress — that have contributed to the development of this hybrid aircraft technology.

Related ReadingWhat Are Electric Planes?

 

10 Examples of Space Planes

Space Rider is an unmanned robotic laboratory used to conduct experiments in microgravity. | Video: ESA

Space Rider

Space Rider is a multi-use, uncrewed robotic laboratory built by the European Space Agency that’s set to launch in late 2025. It’s designed as an “affordable” end-to-end launch service that provides commercial access to space. At about the size of two minivans, the 4,900 kilogram vehicle can carry a payload of 600 kilograms in low orbit for two months at a time. With 600 watts of power, thermal control, data-handling and telemetry capability, Space Rider allows customers to conduct experiments in microgravity that support research across pharmaceutics, biomedicine, biology and physical science.

 

Dream Chaser plans to ferry cargo from Earth to the International Space Station in a 2024 mission. | Video: Sierra Space

Dream Chaser

Built by Sierra Space, Dream Chaser is a reusable, lifting-body commercial space plane designed to carry up to seven people and more than six tons of cargo to and from low Earth orbit. Each model, about the size of a school bus, can fly up to 15 missions. In partnership with NASA, the space plane’s first mission is set for 2024, where an uncrewed, remotely controlled Dream Chaser will resupply the International Space Station with 7,800 pounds of cargo — including food, water and research materials.

 

The X-15 was the first space plane to reach outer space and remains the fastest on record. | Video: Real Engineering

North American X-15

The North American X-15 is a hypersonic, rocket-powered aircraft that was the first to breach the edge of space, located 100 kilometers from Earth’s surface — making it the original “space plane.” Initially launched in 1959, the winged vehicle was a part of  the X-plane series — a shared project between NASA, the U.S. Air Force and the U.S. Navy — that carried out in-flight experiments from 1959 to 1968. X-15 planes were the first to fly mach 4, 5 and 6. To date, it still holds the record for fastest manned aircraft with a top speed at mach 6.7, or 4,520 miles per hour.

Related ReadingAirships Are on the Rise

 

NASA’s Space Shuttle is regarded as one of the most important aircrafts in history. | Video: NASA Johnson

Space Shuttle

NASA’s Space Shuttle, in operation from 1981 to 2011, was the world’s first reusable spacecraft that was used to carry satellites — including the Hubble Space Telescope — to and from orbit. The crewed, 184-foot vehicle also assisted in building the International Space Station as well as deploying robotic probes Galileo and Magellan to explore Jupiter and Venus, respectively, on separate missions. The Space Shuttle was composed of four major components: the orbiter that housed the crew, the engine, a large external fuel tank and two solid rocket boosters used for liftoff. On record, its longest mission lasted 17.5 days.

 

China’s Shenlong space plane has completed three missions to date. | Video: Sky News Australia

Shenlong

China’s experimental robotic space plane Shenlong, coined the “Divine Dragon,” has completed three missions total, including its maiden voyage in 2020 and a 276-day flight. The aircraft, which is operated by the China National Space Administration, is often described as “mysterious” as little is known about the space plane’s purpose or operational capacity, similar to U.S. military vehicles like the X-37B space plane. On its latest mission in December 2023, Shenlong deployed six unidentified objects into Earth’s orbit that emit signals.

 

Now defunct, SpaceShipOne was the first non-governmental aircraft that sent a human to space. | Video: EAA

SpaceShipOne

Although SpaceShipOne retired within two years of its first launch in 2003, the experimental vehicle goes down in history as the first privately developed space plane capable of spaceflight. Developed by California-based aerospace company Scaled Composites, this crewed aircraft air-launched from its mothership, named White Knight, and was powered by a hybrid rocket motor that helped it reach speeds up to 2,000 miles per hour. In 2004, SpaceShipOne won the Ansari X Prize, a space-aviation competition that awards $10 million to a top non-governmental reusable, crewed spacecraft, as well as the Collier Trophy

 

VSS Unity is a suborbital space plane developed for space tourism. | Video: Virgin Galactic

VSS Unity

VSS Unity is an active suborbital, commercial space plane developed for space tourism. The crewed, rocket-powered aircraft is the second of Virgin Galactic’s fleet, and can seat up to four passengers and two pilots. It’s been a frequent flier since its inaugural flight in 2018, but is scheduled to retire in mid 2024 to make way for a new series of “Delta-class” space planes from the company to launch in 2026. In its travels, VSS Unity only breached 80 kilometers from sea level, which is about 20 kilometers short of the Kármán Line, where space “starts.” Regardless, there’s a waiting list with more than 600 reservations, with tickets starting at $450,000 per seat.

Related ReadingWhy We Send Robots to Space (and 7 Examples)

 

Owned by the U.S. military, Boeing X-37 is a mini Space Shuttle that can remain in flight for 900 days. | Video: Boeing

Boeing X-37

Boeing X-37 is a reusable, robotic spacecraft operated by the United States military. This uncrewed, lifting-body vehicle acts as a mini Space Shuttle, with the capability to remain in flight for more than 900 days and return with experiments for further analysis. Boeing X-37 took its maiden voyage in 2006 and remains active. Currently, it’s embarked on a seventh mission. Given its association with the U.S. Space Force, the nature of its activities remain confidential.

 

This animation demonstrates how the soon-to-launch Ascender manages sub-orbital flight. | Video: Bristol Spaceplanes

Ascender

Ascender is a small, two-seater sub-orbital space plane with a minimalist design for the purpose of space tourism. Developed by British aerospace company Bristol Space Planes, the privately funded aircraft can climb up to 100 kilometers and reach a maximum mach 3 speed. While Ascender has achieved EUREKA status as a suggested project by the ESA, it remains in the conceptual stage. According to the company’s website, Ascender may be able to begin test flights before 2030.

 

Radian One aims to be the first single-stage-orbit space plane with horizontal take-off and landing. | Video: PortalTele

Radian One

Developed by a Washington-based aerospace startup, Radian One is a conceptual, five-seater space plane capable of reaching outer space without any extra help from external hardware, like rockets, as well as horizontal take-off and landing. The company claims that its aircraft, which are about the size of a shipping container, will be able to carry out up to 100 missions each, with its first flight launching before 2030

Hiring Now
Consensus Cloud Solutions
Artificial Intelligence • Cloud • Healthtech • Information Technology • Software • Business Intelligence
SHARE