Engineering:SpaceX CRS-33

SpaceX CRS-33

Cargo Dragon fires its Draco engines as it approaches ISS
Names	CRS SpX-33
Mission type	ISS resupply
Operator	SpaceX
Mission duration	164 days, 16 hours and 40 minutes (in progress) 3 months (planned)
Spacecraft properties
Spacecraft	Cargo Dragon
Spacecraft type	Cargo Dragon
Manufacturer	SpaceX
Start of mission
Launch date	August 24, 2025, 06:45:36 UTC (2:45:36 am EDT)
Rocket	Falcon 9 Block 5 (B1090.7), Flight 520
Launch site	Cape Canaveral, SLC‑40
End of mission
Recovered by	(planned)
Landing date	December 2025 (planned)
Landing site	Pacific Ocean near Los Angeles, Oceanside, or San Diego (planned)
Orbital parameters
Reference system	Geocentric orbit
Regime	Low Earth orbit
Perigee altitude	374 km (232 mi)
Apogee altitude	377 km (234 mi)
Inclination	51.6°
Docking with ISS
Docking port	Harmony forward
Docking date	August 25, 2025, 11:05 UTC
Undocking date	December 2025 (planned)
Time docked	163 days, 12 hours and 20 minutes (in progress)
Cargo
Mass	2,300 kg (5,100 lb)
Mission insignia Commercial Resupply Services   Cargo Dragon flights

SpaceX CRS-33, also known as SpX-33, is a International Space Station (ISS) 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 9 meters per second (20 mph) 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 are scheduled to begin in September 2025 and continue periodically through the fall. The first reboost attempt was prematurely aborted.

Manifest

The spacecraft was loaded with a total of 2,300 kg (5,100 lb) 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: 1,091 kg (2,405 lb)
• Science investigations: 447 kg (985 lb)
• Spacewalk equipment: 55 kg (121 lb)
• Vehicle hardware: 587 kg (1,294 lb)
• Computer resources: 35 kg (77 lb)

Return and disposal

The spacecraft is scheduled to remain docked until December 2025, 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.

See also

• Uncrewed spaceflights to the International Space Station