Dream Chaser Spaceplane: Sierra Space's Run to the Station

The era of the space shuttle ended in 2011, leaving a gap in the ability to land spacecraft on a runway. For over a decade, capsules that splash down in the ocean have dominated orbital return. Sierra Space is about to change that dynamic. Their Dream Chaser spaceplane, specifically the first vehicle named Tenacity, is in the final stages of preparation for its maiden cargo flight to the International Space Station (ISS). This mission represents a significant shift in how we transport goods to and from low-Earth orbit.

The Return of the Lifting Body

The Dream Chaser is distinct from the capsules currently used by SpaceX and Boeing. It is a “lifting body” spacecraft. This means the shape of the vehicle itself generates lift as it flies through the atmosphere. It looks strikingly like a miniaturized NASA Space Shuttle, roughly one-quarter of the size.

This design allows for a gentle reentry profile. While capsules experience high G-forces during a ballistic reentry, the Dream Chaser glides home. This results in reentry forces as low as 1.5 g. This is critical for returning delicate science experiments from the ISS, such as protein crystals or biological samples, which might be damaged by a violent splashdown.

The Vehicle: Tenacity

The first spaceplane in the Sierra Space fleet is named Tenacity. It is designed to be highly reusable. Sierra Space engineers have built the vehicle to fly a minimum of 15 missions. This reusability is central to the economics of the program, drastically lowering the cost of access to space over time.

Unlike the toxic hydrazine fuel used by the Space Shuttle’s maneuvering thrusters, Tenacity utilizes a cleaner, non-toxic propellant combination of kerosene (RP-1) and hydrogen peroxide. This allows ground crews to approach the vehicle almost immediately after it lands on the runway, speeding up the process of unloading critical cargo.

Mission Profile: The Maiden Flight

The upcoming mission is a demonstration flight required under NASA’s Commercial Resupply Services-2 (CRS-2) contract. The objective is to prove that Tenacity can launch, dock autonomously, and return safely.

Launch and Orbit

The Dream Chaser does not launch under its own power. It sits atop a rocket inside a protective fairing. For this maiden flight, Sierra Space has partnered with United Launch Alliance (ULA). The spaceplane will launch on ULA’s new Vulcan Centaur rocket from Space Launch Complex 41 at Cape Canaveral Space Force Station in Florida.

Because the spaceplane has wings, it must be folded inside the rocket’s fairing. Once the rocket reaches orbit, the fairing deploys, and Tenacity extends its wings and solar arrays to begin its pursuit of the space station.

The Shooting Star Module

The Dream Chaser does not fly alone. Attached to the rear of the plane is the “Shooting Star” cargo module. This 15-foot attachment serves several purposes:

  • Power and Support: It carries solar panels that generate power for the vehicle during transit.
  • Extra Cargo: It holds up to 7,000 pounds of pressurized and unpressurized cargo.
  • Disposal: unlike the spaceplane, the Shooting Star module is not reusable. Before reentry, it separates from the Dream Chaser and burns up in the Earth’s atmosphere. This provides a necessary service to the ISS by disposing of thousands of pounds of station trash.

Landing at Kennedy Space Center

After spending approximately 45 days docked to the ISS, Tenacity will undock and begin its return. It will perform a deorbit burn and glide back to Earth. The target landing site is the Launch and Landing Facility (formerly the Shuttle Landing Facility) at Kennedy Space Center. This will be the first time a commercial spacecraft lands on a runway like an airplane from orbit.

Why Runway Landings Matter

The ability to land on a standard runway offers logistical advantages over ocean splashdowns.

  1. Immediate Access: When a capsule splashes down, recovery ships must travel to the site, hoist the capsule, and transport it to port. This takes hours or days. With a runway landing, science teams can access the cargo bay within minutes of “wheels stop.”
  2. Global Compatibility: While the primary landing site is in Florida, the Dream Chaser is compatible with commercial runways anywhere in the world, provided they are at least 10,000 feet long. This opens the possibility of returning cargo directly to Europe or Japan in future missions.
  3. Gentle Handling: The low-G entry protects sensitive payloads. For pharmaceutical companies manufacturing drugs in microgravity, this gentle return is a vital feature.

Current Status and Testing

As of late 2024, Tenacity has been undergoing rigorous environmental testing. This includes thermal vacuum testing at NASA’s Neil Armstrong Test Facility in Ohio, where the vehicle was subjected to the extreme freeze of space and the intense heat of the sun.

Following these tests, the vehicle moved to the Space Systems Processing Facility (SSPF) at Kennedy Space Center. Here, technicians are installing the final thermal protection tiles (the heat shield) and integrating the vehicle with the Shooting Star module. The teams are working through the final checklist to clear the vehicle for integration with the ULA Vulcan rocket.

Frequently Asked Questions

Will the Dream Chaser carry astronauts? Not on this flight. The current version, the DC-100, is designed strictly for cargo. However, Sierra Space plans to build a crewed version, the DC-200, which will be capable of carrying up to seven astronauts to low-Earth orbit in the future.

When will the first launch happen? Spaceflight schedules are fluid. Sierra Space and ULA are targeting the latter part of 2024 or early 2025 for the first mission. The exact date depends on the readiness of the Vulcan Centaur rocket and final certification from NASA.

How much cargo can it carry? The total system (Dream Chaser plus the Shooting Star module) can deliver up to 12,000 pounds (5,500 kg) of supplies to the International Space Station. It can return approximately 4,000 pounds (1,850 kg) of cargo back to Earth.

Is this a NASA vehicle? No. Dream Chaser is owned and operated by Sierra Space, a commercial company. NASA is a customer purchasing freight services, similar to how they purchase flights from SpaceX and Northrop Grumman.