SpaceX Falcon 9 Block 5 - CRS-25 SpX-25 - Launching July 14/15, 2022
Screenshot from NASA/SpaceX shared Webcast of the CRS-25
Mission Rundown: SpaceX Falcon 9 Block 5 - CRS-25
Written: July 30, 2022
Dragon’s up and about this evening
Dragon CRS-2 SpX-25 (CRS-25) is a Commercial Resupply Service mission that flew to the International Space Station (ISS). SpaceX was awarded this mission by NASA back in 2016 and launched it on its Falcon 9 Block 5 rocket using a Cargo Dragon 2, C208-3.
The rocket lifted off on July 14, 2022 at 20:44 EDT - July 15, 2022 at 00:44:20 UTC from Launch Complex 39A, at the Kennedy Space Center in Florida.
CRS-25 was the fifth flight for SpaceX under NASA’s CRS Phase 2 contract and SpaceX’s 30th launch in 2022 compared to a total of 31 launches in 2021. On board are ~2,650 kg (~5,800 lb) of food, hardware, and scientific research.
Dragon C208-3 separated from the second stage of the Falcon 9 Block 5 at ~T+12 min. After that, it performed a series of thruster firings to adjust its orbit and reach the ISS. The spacecraft arrived at the ISS ~38 hours later, on July 16, at 15:21 UTC (11:21 EDT). Dragon autonomously docked to the ISS’ Harmony module’s zenith – or space-facing – port.
Upon Dragon’s arrival, the crew proceeded with unloading the cargo.
After boosting the second stage along with Cargo Dragon 2, C208-3 towards orbit, the first stage will perform a 20 second re-entry burn to slow the vehicle down in preparation for atmospheric reentry. The booster will then perform a 20-25 second landing burn aboard one of SpaceX’s autonomous spaceport drone ships.
B1067-5 will launch CRS-2 SpX-25 to the International Space Station and upon completion of this first launch with CRS-25, the boosters changes designation to B1067-5.
B1067-5 didn’t perform a static fire test after refurbishment and waiting for an east coast launch out of the Cape. SpaceX has since Starlink V1.0 L08 omitted this safety precaution many times so far. It is not required to perform a static fire test in house missions like Starlink. Only one mission other than Starlink has omitted the static fire test.
Returning to Earth from ISS
Dragon C208-3 will spend around one month at the ISS with its mission ending in August. After that, the spacecraft will travel back to Earth and will splash down under parachutes off the coast of Florida, returning valuable research and cargo to Earth.
After a month-long stay at the International Space Station, NASA and SpaceX will have successfully returned the CRS-25 Cargo Dragon back to Earth.
The CRS 2 contract employs the Dragon 2 spacecraft, as the Dragon 1 spacecraft was retired at the end of the initial CRS contract after 19 CRS missions plus the COTS 2+ visit to ISS. CRS-7 was destroyed mid-flight by a loose COPV in the second stage.
Since its maiden flight, Dragon 2 has flown 15 times; seven crewed and eight uncrewed.
Where to land the Dragon?
Seven hazard areas for Dragon C212-1 - Recovery Location LZ 5 Cape Canaveral is chosen
The opportunity for CRS-25 to return to Earth has been determined; they are still in orbit on ISS and docked to IDA-3 now known as IDA-Z airlock - Z for zenit.
The CRS-25 Cargo Dragon spacecraft is scheduled to undock from the International Space Station at 11:05 EST - 15:05 UTC Thursday, August 19, to begin the journey home.
NASA’s SpaceX CRS-25 mission now is targeting a splash down on Earth no earlier than 14:53 EST - 18:53 UTC on August 20, 2022 near Cape Canaveral.
The Cargo Dragon spacecraft will aim for a splashdown at one of seven targeted landing zones in the Atlantic Ocean or Gulf of Mexico off the coast of Florida. Recovery is in the splashdown zone 5 in the Atlantic Ocean.
The recovery ship Megan is loitering around LZ-7 so near Cape Canaveral it’s just a daytrip.
CRS-25 will after the trunk is jettisoned perform its deorbit burn at 14:04 EST - 18:04 UTC and close the nose hatch cover. Then CRS-25 will reorient itself with its heat shield forward and enter the Earth's atmosphere.
Four minutes before splashdown, the drogue parachutes will deploy at about 18,000 feet in altitude while the Cargo Dragon is moving approximately 350 miles per hour, and less than a minute later, the main parachutes deploy at about 6,000 feet in altitude while the spacecraft is moving approximately 119 miles per hour.
For normal crew rescue and recovery operations, the NASA and SpaceX teams select two primary splashdown locations from the seven possible locations about two weeks prior to return, with additional decision milestones taking place prior to crew boarding the spacecraft, during free flight, and before the Cargo Dragon performs a deorbit burn.
NASA and SpaceX coordinate with the U.S. Coast Guard to establish a 10-nautical-mile safety zone around the expected splashdown location to ensure safety for the public and for those involved in the recovery operations, as well as the cargo aboard the returning CRS-25 spacecraft.
Teams on the Megan recovery ship, including two fast boats, will be securing CRS-25 Cargo Dragon and ensuring the spacecraft is safe for the recovery effort. As the fast boat teams complete their work, the recovery ship will move into position to hoist the Cargo Dragon onto the main deck of the ship.
Once on the main deck, the important and time-sensitive research samples will be taken out of the spacecraft before a helicopter ride back to Cape Canaveral.
The discarded Dragon trunk from the CRS-25 mission, jettisoned on August 19, has now been cataloged in a 210 x 394 km x 51.3 deg orbit. 11 days later it is predicted to reenter at 07:55 UTC August 31 over the eastern Central Africa area.
A low apogee of 210 km in this orbit must have been the contributing factor in deorbiting the Dragon trunk section so fast. It is after all a BIG barrel or dustbin, so maybe it should be rebuilt as a space debris hunter gatherer collecting space junk.
Hmm. How can that come about? Hall effect Ion thrusters? Pincers? Radar?
Cargo Dragon Payload
Dragon C208-3 separated from the second stage of the Falcon 9 Block 5 at ~T+12 min. After that, it performed a series of thruster firings to adjust its orbit and reach the ISS. The spacecraft arrived at the ISS ~38 hours later, on July 16, at 15:21 UTC (11:21 EDT). Dragon autonomously docked to the ISS’ Harmony zenit module after soft capture.
Soft capture is the first contact between the spacecraft and the space station. A “soft” capture ring hooks to its counterpart on the docking port and slowly retracts to bring in Dragon for hard capture. Just 10 minutes later a hard capture was confirmed after the 12 hooks secured the spacecraft to the space station.
After leak checks and pressurization of the vestibule (the small space between station and Dragon), the hatch to C208-3 was opened granting the crew access to the cargo inside.
Dragon C208-3 will spend around one month at the ISS. Its mission will end in late August or early September. After that, the spacecraft will travel back to Earth and will splash down under parachutes off the coast of Florida, returning valuable research and cargo to Earth.
Starting with CRS-23 SpX-23, SpaceX’ cargo missions will have an extended duration – from two months and beyond if chosen.
Dragon C208-3 can double as an extra space science laboratory where 4 experiments will share power, downlink data streams and data storage from Dragon C208-3 internal supply. One experiment will be moved from its current home on ISS to its new location on Dragon C208-3, where it will join 3 already installed experiments.
The redesign of Cargo Dragon Capsules will extend ISS ability to conduct experiments, and it seems ISS is due for an extension with an extra laboratory module some time soon.
CRS-25 research payloads
Arriving on board Cargo Dragon C208-3 are dozens of science experiments and technology demonstrations. The following list is only an excerpt of what has been ferried to the ISS. More information on the different science payloads can be found on the websites of NASA and the ISS National Lab.
Materials International Space Station Experiment-16-Commercial
Study of Induced Pluripotent Stem Cells (iPSCs) in Microgravity
ELaNa 45 CubeSats On CRS-25
ELaNa is an initiative that was proposed by NASA and is managed by the Launch Services Program (LSP) at NASA’s Kennedy Space Center. The main aim of this program is to collaborate with universities all across the US to design, manufacture, and launch research satellites into space. ELaNa brings university students closer to real space missions, giving them opportunities to dive in and get involved in the process from A to Z, from designing and assembling CubeSats, to launching and operating them.
ELaNa 45 consist of the following CubeSats:
BeaverCube – Massachusetts Institute of Technology, Cambridge, Massachusetts
CapSat-1 – The Weiss School, Palm Beach Gardens, Florida
CLICK A – NASA’s Ames Research Center, Mountain View, California
D3 – Embry-Riddle Aeronautical University, Daytona Beach, Florida
JAGSAT – University of South Alabama, Mobile, Alabama
The Cargo Dragon 2
Dragon capsule C208 during processing at SpaceX HQ in Hawthorne prior to CRS-21
Cargo Dragon 2 is essentially a Crew Dragon, without an abort system, so it has all of the upgrades from Crew Dragon. Most importantly, Dragon 2 is designed to be reused up to 5 times, with a turnaround time of under 6 months, which is significantly lower than Dragon One; Dragon One’s fastest turnaround time was 418 days, with most turnaround times being significantly longer.
Dragon 1 was unable to dock with the International Space Station. Meaning that Dragon 1 would hold a position away from the ISS. In this position the Canadarm would capture the spacecraft, and attaching it to the ISS. This is called berthing.
Dragon 2 autonomously attaches itself and docks to the ISS. CRS-25 will mark the twelfth fully autonomous docking SpaceX has completed: DM-1, DM-2, Crew-1, CRS-21, Crew-2, CRS-22, CRS-23, Crew-3, CRS-24, Axiom, Crew-4 and now CRS-25.
Cargo Dragon 2’s trunk is also different from Dragon 1 and Crew Dragon 2, that has its solar panels integrated onto its trunk, while Dragon 1 had a deployable solar array from its trunk. However, Crew Dragon 2 is equipped with 4 fins, which are used for aerodynamic control during ascent. Cargo Dragon 2’s trunk only has 2 solar cell fins.
Externally, Cargo Dragon 2 differs from its crewed counterpart, lacking windows and the SuperDragon abort system. The differences between Crew Dragon and Cargo Dragon are derived from the fact that Cargo Dragon is not required to have launch escape capability. Crew Dragon is fitted with eight SpaceX-developed SuperDraco engines, located in four, two engine clusters around the outside of the capsule, which are there to pull the capsule and its crew to safety away from a Falcon 9 in the event of a catastrophic failure during fueling or launch.
Since Cargo Dragon does not carry crew, the spacecraft does not have to carry those systems; therefore the SuperDracos have been removed from the Cargo Dragon capsule giving a mass reduction that allows for additional cargo to be carried to ISS.
Cargo Dragon 2 also lacks most of the life support and onboard control systems present on Crew Dragon that are needed for humans. Instead, it carries minimal support systems to ensure conditions are kept acceptable for hatch opening on the Station and ISS Crew ingress to the vehicle.
Cargo Dragon 2 is also significantly more massive, with a dry mass of ~12,000 kg. With this mass increase Dragon 2 is able to carry ~50% more science to the ISS than Dragon One. Because of this, missions after CRS-21 will stay docked to the ISS for 3 months, rather than the 1 month that CRS-21 stayed docked.
Dragon 2’s nose cone is also significantly different as it opens instead of being jettisoned on ascent. It is protecting the docking mechanism.
At a press conference after Crew-1, Gwynne Shotwell said SpaceX is expecting to have a fleet of 8 dragons: 5 Crew Dragons and 3 Cargo Dragons. This will allow SpaceX to conduct up to 25 crewed missions and 15 resupply missions.
Unlike prior cargo resupply missions, the new Cargo Dragon 2 carried too much mass to permit a Return To Launch Site (RTLS) landing of the Falcon 9 first stage. Instead, the first stage — like Crew Dragon, from which Cargo Dragon is now derived — made use of a newly built drone ship “A Shortfall Of Gravitas'' in the Atlantic for landing and recovery.
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