SpaceX CRS-33


SpaceX CRS-33, also known as SpX-33, is a International Space Station cargo resupply mission contracted by NASA and operated by SpaceX. The flight, launched on August 24, 2025 from Space Launch Complex 40 at Cape Canaveral Space Force Station, is SpaceX's 33rd cargo delivery mission under the Commercial Resupply Services program and the company's 50th overall Dragon flight to the ISS, including both cargo and crew missions.

Boost kit demonstration

A distinguishing feature of this mission is the inclusion of a "boost kit" propulsion module in Dragon's hollow unpressurized trunk, which is typically used to carry larger experiments that are robotically attached to the outside of the ISS. The kit comprises six dedicated propellant tanks containing hydrazine and nitrogen tetroxide, a helium pressurant tank, and two Draco thrusters aligned with the station's velocity vector. The boost kit is based on, but operates independently from Dragon's primary propulsion system. When activated, the system can add about to the ISS's orbital velocity, equivalent to the total reboost impulse of roughly one-and-a-half Russian Progress cargo vehicles, which are normally responsible for orbit maintenance. The kit carries enough propellant to provide about one-third to one-fourth of the ISS's annual reboost needs. Demonstration reboosts began in September 2025. the spacecraft has performed five reboosts, and a final reboost is planned.

Manifest

The spacecraft was loaded with a total of of cargo, including scientific experiments, crew provisions, and fresh food such as 1,500 tortillas. Research equipment aboard the flight supports investigations into 3D printing in microgravity and the effects of long-duration spaceflight on the human body.
The cargo manifest is broken down as follows:
  • Crew supplies:
  • Science investigations:
  • Spacewalk equipment:
  • Vehicle hardware:
  • Computer resources:

    Return and disposal

The spacecraft is scheduled to remain docked until January 2026, when it will undock and return research samples and cargo to Earth with a parachute-assisted splashdown in the Pacific Ocean off California. The pressurized capsule will be recovered for refurbishment and reuse, while the trunk containing the boost kit will be discarded to burn up in the atmosphere.