Screenshot from NASA/SpaceX shared Webcast of the CRS-26. LOX lines are being chilled down
Mission Rundown: SpaceX Falcon 9 - CRS-26
Written: November 27, 2022 - Edit: January 20, 2023
Mr. Dragon. Your ride is here
Dragon CRS-2 SpX-26 (CRS-26) 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 rocket B1076-1 using Cargo Dragon, C211-1.
Three different vehicles from three different entities have the capability to carry cargo to the ISS. Northrup Grumman’s Cygnus spacecraft launched by NASA, ROSCOSMOS’s Soyuz Progress spacecraft, and SpaceX’s Cargo Dragon spacecraft.
Cygnus recently launched a resupply mission to the ISS with the S.S. Sally Ride vehicle on their CRS-2 NG-18 mission from Wallops Island, Virginia, USA. The last Progress launch was in late October on the Progress MS-21 mission. SpaceX’s Cargo Dragon spacecraft is the only one with a cargo return capability.
The Falcon 9 rocket lifted off on November 26, 2022 at 14:20 EST - 19:20:43 UTC from historic Launch Complex 39A, at the Kennedy Space Center in Florida.
CRS-26 was the sixth flight for SpaceX under NASA’s CRS Phase 2 contract and SpaceX’s 53rd 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 C211-1 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 ~17 hours later, on November 27, at 12:30 UTC (07:30 EST).
Dragon autonomously docked to the ISS’ Harmony module’s forward-facing port. Upon Dragon’s arrival, the crew will proceed with unloading the cargo.
After boosting the second stage along with Cargo Dragon 2, C211-1 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.
B1076-1 will launch CRS-26 to the International Space Station on its maiden voyage.
B1076-1 doesn't need to perform a static fire test because it’s brand new and is ready and waiting for an east coast launch out of the Cape. SpaceX has since omitted this safety precaution many times so far. It is not required to perform a static fire test in house missions like Starlink. Other SpaceX customers have omitted the static fire test.
The Cargo Dragon mission
Dragon C211-1 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 ~17 hours later. 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 C211-1 was opened granting the crew access to the cargo inside.
Dragon C211-1 will spend 45 days at the ISS. Its mission will end in mid January. 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.
The CRS 2 contract employs SpaceX’s Dragon 2 spacecraft now on its 26th mission to the International Space Station , as the Dragon 1 spacecraft was retired at the end of the initial extended CRS 1 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.
Dragon 2 has flown under its own power 17 times; eight crewed and nine uncrewed.
Dragon C211-1 can double as an extra space science laboratory where 4 experiments will share power, downlink data streams and data storage from Dragon C211-1 internal supply. One experiment will be moved from its current home on ISS to its new location on Dragon C211-1, 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.
Dragon research payloads
Arriving on board Cargo Dragon C211-1 are dozens of science experiments and technology demonstrations. The following list is only an excerpt of what has been ferried to the ISS.
CRS-26 carries experiments ranging from vegetation experiments to new solar arrays for the ISS to provide greater power consumption. These research experiments can range from NASA-funded experiments to private companies and universities. If you’d like to learn more, reach out or explore NASA’s website and the ISS National Lab.
The Moon Microscope experiments, also known as the long-winded Moon Medicine: Blood Staining and Novel Miniaturized Imaging Technology to Facilitate Critical Lunar Diagnosis, is aimed at developing a way to analyze blood smear samples from astronauts in a light and compact instrument in minutes.
The Extrusion experiment will be sending a lot of liquid resin to the International Space Station (ISS), and for very good reason. On Earth, people build structures like bridges and buildings to withstand gravity. Similar structures can be built differently in a reduced or microgravity environment.
The Vegetable Production System (Veggie) is an experiment aimed at producing fresh and plentiful crops on station. Unlike some experiments of similar nature before it, Veggie uses more of the environment in the cabin such as pulling from its temperature and carbon dioxide instead of regulating those itself.
Two iROSAs rollable solar arrays will be launched to the International Space Station on CRS-26. These solar arrays will provide a 20% to 30% increase in power consumption for the ISS. Each array has been built from a composite carbon fiber which allows it to be rigid when deployed, by curl-up like a tape measure when stowed. The rolling and lightweight components of the iROSAs are better than other heavier, non-rolling solar arrays.
ELaNa 49 CubeSats on CRS-26
These six CubeSats were selected through NASA’s CubeSat Launch Initiative (CSLI), which provides U.S. educational institutions, nonprofits with an education/outreach component, informal educational institutions (museums and science centers), and NASA centers with access to space at a low cost. + Two more: DanteSat and NutSat. Link
Two Canadian cubesats are also onboard: LORIS - A 2U CubeSat built by Dalhousie University link and ORCASat - A 2U CubeSat built by University of Victoria link.
TJREVERB - The 6U CubeSat built by the Thomas Jefferson High School for Science and Technology Research and Education aims to study the use of iridium as a primary radio communication method. Additionally, the satellite will demonstrate the use of a passive magnet onboard and the Earth’s magnetic field for stabilization rather than using an attitude determination and control system for pointing accuracy and stabilization for iridium.
MARIO - The 6U CubeSat built by the University of Michigan - Measurement of Actuator Response In Orbit - is a technology demonstration that will show how test structures made of a piezoelectric material – a type of material that bends when electricity is applied and can also generate electricity when bent – perform in low-Earth orbit.
PetitSat - The 6U CubeSat built by the NASA Goddard Space Flight Center will study density irregularities in the Earth’s ionosphere – a tiny fraction of the atmosphere made of plasma, or ionized gas. During long distance radio communication, the ionosphere reflects radio waves back to Earth.
SPORT - The 6U CubeSat built by the NASA Marshall Space Flight Center called Scintillation Prediction Observations Research Task (SPORT) will also look to the ionosphere to study space weather. The joint mission of the U.S. and Brazil will examine the formation of plasma bubbles, which scatter radio signals.
Where to land the Dragon?
Seven hazard areas for Dragon C211-1 - Recovery Location LZ 1-7 available - LZ 4 Tampa is chosen
The opportunity for CRS-26 to return to Earth has been determined; they are still in orbit on ISS and docked to IDA-2 now known as the forward facing airlock.
The CRS-26 Cargo Dragon spacecraft is scheduled to undock from the International Space Station at 17:05 EST - 22:05 UTC on January 9, 2023 to begin the journey home.
NASA’s SpaceX CRS-26 mission now is targeting a splash down on Earth no earlier than 05:20 EST - 10:20 UTC on January 11, 2023 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 4 in the Mexican Gulf near Tampa, Florida.
The recovery ship Megan was loitering around LZ-4 so near Tampa it’s no longer a short trip back
CRS-26 will after the trunk is jettisoned perform its deorbit burn at 04:42 EST - 09:42 UTC and close the nose hatch cover. Then CRS-26 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-26 spacecraft.
Teams on the Megan recovery ship, including two fast boats, will be securing CRS-26 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-26 mission, jettisoned on January 11, was in a 210 x 394 km x 51.3 deg orbit. It deorbited 10 days later at 18:28 UTC January 28 over northern Peru near the area at 74o west 4o south.
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.
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.
CRS-26 will mark the 15th autonomous docking to the ISS that SpaceX has completed: DM-1, DM-2, Crew-1, CRS-21, Crew-2, CRS-22, CRS-23, Inspiration4, Crew-3, CRS-24, Axiom, Crew-4, CRS-25, Crew-5 and now CRS-26.
In this G. DE CHIARA drawing of DM-2 there are measurement sticks inserted by Me; the side section has been split to separate the capsule and the trunk. Haven’t found a Cargo Dragon.
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, twin 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 as seen in the inflight abort mission.
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 can stay docked to the ISS for up to 3 months, rather than the one 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 new drone ship “A Shortfall Of Gravitas'' in the Atlantic for landing and recovery.
