SpaceX’s oldest Crew Dragon spacecraft launched Sunday night time on its fifth mission to the Worldwide House Station, and engineers are crunching information to see if the fleet of Dragons can safely fly as many as 15 occasions.
It has been 5 years since SpaceX launched the primary Crew Dragon spacecraft on an unpiloted take a look at flight to the house station, and almost 4 years since SpaceX’s first astronaut mission took off in Could 2020. Since then, SpaceX has put its clan of Dragons to make use of ferrying astronauts and cargo to and from low-Earth orbit.
Now, it is already time to speak about extending the lifetime of the Dragon spaceships. SpaceX and NASA, which shared the price of creating the Crew Dragon, initially licensed every capsule for 5 flights. Crew Dragon Endeavour, the primary within the Dragon fleet to hold astronauts, is now flying for the fifth time.
This ship has spent 466 days in orbit, longer than any spacecraft designed to move folks to and from Earth. It can add roughly 180 days to its flight log with this mission.
Crew Dragon Endeavour lifted off from Florida aboard a Falcon 9 rocket at 10:53 pm EST Sunday (03:53 UTC Monday), following a three-day delay as a consequence of poor climate situations throughout the Atlantic Ocean, the place the capsule would ditch into the ocean within the occasion of a rocket failure through the climb into orbit.
Commander Matthew Dominick, pilot Michael Barratt, mission specialist Jeanette Epps, and Russian cosmonaut Alexander Grebenkin placed on their SpaceX stress fits and strapped into their seats inside Crew Dragon Endeavour Sunday night at NASA’s Kennedy House Middle. SpaceX loaded liquid propellants into the rocket, whereas floor groups spent the ultimate hour of the countdown evaluating a small crack found on Dragon’s aspect hatch seal. Managers in the end cleared the spacecraft for launch after contemplating whether or not the crack may pose a security risk throughout reentry on the finish of the mission.
“We’re assured that we perceive the problem and may nonetheless fly the entire mission safely,” a member of SpaceX’s mission management crew instructed the crew inside Dragon.
This mission, often called Crew-8, launched on a model new Falcon 9 booster, which returned to touchdown a couple of minutes after liftoff at Cape Canaveral House Drive Station. The Falcon 9’s higher stage launched the Dragon spacecraft into orbit about 12 minutes after liftoff. The four-person crew will dock on the house station round 3 am EST (0800 UTC) Tuesday.
Crew-8 will substitute the four-person Crew-7 crew that has been on the house station since final August. Crew-7 will return to Earth in about one week on SpaceX’s Crew Dragon Endurance spacecraft, which is flying in house for the third time.
The Crew-8 mission come residence for a reentry and splashdown off the coast of Florida in late August of this yr, wrapping up Crew Dragon Endeavour’s fifth journey to house. That is the present life restrict for a Crew Dragon spacecraft, however do not depend out Endeavour simply but.
Fleet administration
“Proper now, we’re licensed for 5 flights on Dragon, and we’re taking a look at extending that life out,” mentioned Steve Stich, NASA’s industrial crew program supervisor. “I believe the objective can be for SpaceX to say 15 flights of Dragon. We might not get there in each single system.”
One after the other, engineers at SpaceX and NASA are taking a look at Dragon’s structural skeleton, composite shells, rocket engines, valves, and different elements to see how a lot life is left in them. Some elements of the spacecraft slowly fatigue from the stresses of every launch, reentry and splashdown, together with the acute temperature swings the capsule sees hundreds of occasions in orbit. Every Draco thruster on the spacecraft is licensed for a sure variety of firings.
Some elements are already accredited for 15 flights, Stich mentioned in a latest press convention. “Some, we’re nonetheless in the course of engaged on,” he mentioned. “A few of these elements should undergo some re-qualification to guarantee that they will make it out to fifteen flights.”
Re-qualifying a element on a spacecraft usually includes placing {hardware} via in depth testing on the bottom. As a result of SpaceX reuses {hardware}, engineers can take away an element from a flown Dragon spacecraft and put it via qualification testing. NASA will get the ultimate say in certifying the Dragon spacecraft for added flights as a result of the company is SpaceX’s major buyer for crew missions.
The Dragon fleet is flying extra typically than SpaceX or NASA initially anticipated. The principle purpose for that is that Boeing, NASA’s different industrial crew contractor, is operating about 4 years behind SpaceX in attending to its first astronaut launch on the Starliner spacecraft.
When NASA chosen SpaceX and Boeing for multibillion-dollar industrial crew contracts in 2014, the company envisioned alternating between Crew Dragon and Starliner flights each six months to rotate four-person crews on the Worldwide House Station. With Boeing’s delays, SpaceX has picked up the slack.
The Boeing delays have been good for SpaceX within the sense that NASA has awarded contract extensions to hold the Crew Dragon program via the top of the 2020s. NASA has bought 14 operational Crew Dragon flights from SpaceX, in comparison with six Starliner flights from Boeing. On Sunday night time, SpaceX launched the eighth operational Crew Dragon flight for NASA, and the thirteenth crew flight on Dragon general.
Whereas SpaceX is flying astronauts for NASA, the corporate can be launching all-private crews to orbit via offers with the Houston-based firm Axiom House and billionaire Jared Isaacman, who plans to carry out the primary industrial spacewalk later this yr.
Enterprise is booming, however SpaceX is reaching certification limits on the Dragon spacecraft quicker than anticipated.
SpaceX has 4 human-rated Dragon spaceships, plus three Dragons designed for cargo missions. A fifth Crew Dragon is on monitor for completion later this yr, and can most likely make its first flight in early 2025, in response to Stich. SpaceX officers have mentioned this would be the ultimate Crew Dragon spacecraft the corporate will construct, and the fleet of 5 capsules shall be sufficient to fulfill demand for Dragon missions till the next-generation Starship automobile is able to take over.
Will probably be a minimum of a number of years, and probably longer, till Starship is licensed for human launches and landings. Till then, Dragons will proceed launching on Falcon 9 rockets, even when some satellite tv for pc missions shift to Starship.
SpaceX has flown a few of its reusable Falcon 9 boosters as many as 19 occasions, almost double the rocket’s unique life expectancy, and is taking a look at certifying Falcon 9s for as many as 40 launches and landings.
Stich mentioned NASA and SpaceX may choose an intermediate variety of flights, someplace between 5 and 15, after they re-certify the Dragon spaceships. A later spherical of testing and opinions may ultimately get to SpaceX’s 15-flight objective. “I want to get out to seven to 10 flights for Dragon, however we’ll see the place we get,” he mentioned.
There are some elements, like warmth protect materials and parachutes, that SpaceX nonetheless wants to exchange after every flight.
It is all the time the valves
Throughout preparations for the Crew-8 mission, SpaceX technicians swapped out valves contained in the spacecraft’s propulsion system that appeared to point out indicators of corrosion. The valves management the circulation of propellant to the Draco thrusters wanted to maneuver the spacecraft in orbit, and to the extra highly effective SuperDraco engines that may solely fireplace within the occasion of a launch abort.
“We have had some valve corrosion within the oxidizer valves, each on the low stress aspect which is used on orbit, after which the aspect for aborts,” Stich mentioned.
The Draco and SuperDraco thrusters eat a hypergolic combination of propellants. Hydrazine is the gasoline and nitrogen tetroxide is the oxidizer, and the propellants ignite after they are available in contact with each other. Stich mentioned technicians changed a number of kinds of valves within the oxidizer aspect of the propulsion system, together with tank isolation valves, Draco manifold valves, and throttle valves for the SuperDraco abort engines.
“All these had been associated to corrosion,” Stich mentioned. “I’d say all of them had been achieved out of an abundance of warning.”
Engineers monitor how the valves cycle throughout checkouts between flights. “If the timing begins to look a little bit uncommon, we’ll go in and substitute these valves,” Stich mentioned.
SpaceX
Invoice Gerstenmaier, SpaceX’s vp of construct and flight reliability, mentioned the valve points may have one thing to do with put on and tear over the course of Crew Dragon Endeavour’s 4 earlier house missions. Nevertheless it most likely has extra to do with environmental components, he mentioned.
“I believe it’s extra how will we preserve the surroundings pristine across the valve and forestall that (corrosion),” Gerstenmaier mentioned. “We might make some design adjustments on the valves sooner or later to work on that space.”
Valve issues are nothing new for SpaceX or just about some other house firm.
Boeing had hassle with corroded valves within the Starliner spacecraft. Investigators traced the reason for that downside to the response of nitric acid with moisture that seeped into the propulsion system. SpaceX apparently detected proof of valve corrosion early, earlier than it manifested right into a extra significant issue like that which grounded a Starliner take a look at flight for almost a yr. Gerstenmaier mentioned SpaceX added purges to the propulsion system to forestall contamination from build up on the valves.
Epps lastly in orbit
Jeanette Epps, a mission specialist on the Crew-8 mission, waited almost 15 years to fly in house after NASA chosen her as an astronaut in 2009.
She was set to turn into the primary Black astronaut to fly a long-duration stint on the house station in 2018, when she was coaching for launch on a Russian Soyuz spacecraft. However NASA changed her with a backup crew member, and the company by no means publicly said a purpose for the crew change.
It is uncommon however not unprecedented for NASA to take away an astronaut from a crew quickly earlier than launch, nevertheless it’s normally for medical causes, like an sickness an damage. In these instances, NASA usually withholds particulars from the general public as a consequence of privateness issues, however the company has recognized a medical subject as the rationale for changing a crew member.
That was not the case for Epps. Some folks outdoors the company theorized Epps might need been faraway from her flight for political or racial causes, however Ars has reported that didn’t look like the case.
Epps, a former CIA expertise intelligence officer, returned from Russia to NASA’s astronaut coaching base in Houston to await one other project. In her public remarks after NASA eliminated her from the Soyuz crew, She was clearly disillusioned. “It’s one thing that I stay with every single day,” Epps mentioned in 2018.
However she declined to “speculate” publicly on the rationale for NASA’s resolution. She mentioned she handed all of her NASA and Russian coaching for the mission. “I did not have any medical situations or something like that,” Epps mentioned in 2018. “And I did not have any household points in any respect, both.”
NASA did make Epps eligible for future flight assignments pretty quickly after she misplaced her Soyuz seat. In 2020, NASA added Epps to the crew slated to fly Boeing’s Starliner crew capsule on its first operational mission to the house station, however NASA later reassigned her to coach for a SpaceX launch after continued delays on Boeing’s Starliner program.
She would probably have flown on SpaceX’s Crew-5 mission in 2022. However NASA and Russia’s house company signed a long-planned barter settlement to permit SpaceX’s Dragon spacecraft to start ferrying Russian cosmonauts to and from the house station and provides US astronauts seats on Russian Soyuz flights. That meant a Russian cosmonaut took the open seat on the Crew-5 mission.
Epps was final member of NASA’s 2009 astronaut class to fly in house. Some astronauts within the 2009 class have already flown twice. In January, she instructed reporters she stored her spirits up by persevering with to coach. Regardless of the lengthy wait to get into house, Epps is among the many few astronauts who’ve skilled to fly on Soyuz, Starliner, and Dragon.
“I’ve been fairly busy over the previous couple of years nonetheless coaching, nonetheless working towards the objective of going to the house station,” Epps mentioned.
Matthew Dominick, the Crew-8 commander, can be a first-time house flier. He was a US Navy take a look at pilot who flew F/A-18 fighter planes earlier than NASA chosen him for the astronaut corps in 2017. Michael Barratt, the Crew-8 pilot and a flight surgeon, is a veteran of two earlier flights to the house station, one on a Soyuz and one other on an area shuttle.
Russian cosmonaut Alexander Grebenkin, one other spaceflight rookie, rounds out the crew. He was a radio communications engineer and served within the Russian navy earlier than becoming a member of Russia’s cosmonaut corps.
March 3, 2024: This story was up to date after the launch of SpaceX’s Crew-8 mission.
