Triumph! SpaceX returns Dragon to service with CRS-8, nails landing on Drone Ship
CAPE CANAVERAL, Fla. — The hits kept right on coming for SpaceX today as the NewSpace firm successfully returned their Dragon spacecraft to service and carried out the first completely successful ocean landing in the company’s history when at approximately 4:52 p.m. EDT (20:52 GMT) the Falcon 9’s first stage successfully touched down on the “Of Course I Still Love You” Autonomous Spaceport Drone Ship (ASDS) positioned out in the Atlantic.
SpaceX launched the CRS-8 mission to the International Space Station (ISS) on April 8, at 4:43 p.m. EDT (20:43 GMT). The launch site for the mission was Cape Canaveral’s Space Launch Complex 40 (SLC-40) in Florida. The flight should see some 7,000 lbs (3,175 kg) of cargo, crew supplies, and experiments arrive at the ISS on Sunday, April 10.
This afternoon’s launch marked the first time that SpaceX’s Dragon has taken to the skies since the June 2015 CRS-7 mishap that saw another Dragon and the Falcon 9 v1.1 rocket explode in the skies above Kennedy Space Center some 139 seconds after it had lifted off of the pad.
SpaceX has already returned the Falcon 9 launch vehicle to flight. In fact, a mere six months had elapsed between the CRS-7 anomaly and the rocket’s return to flight (the Dec. 22, 2015, launch of Orbcomm OG2). Two more flights of the rocket followed in January and March of this year (2016). However, today’s flight was all about the Dragon.
NASA has spent considerable energy highlighting the experiments and technology demonstrators that roared aloft with the Falcon 9 FT.
Included in the payload for this mission were the Veg-03, Micro-10, Genes in Space, and an array of other scientific investigations that will join the 250 or so that are already being carried out on the ISS.
“The cargo will allow investigators to use microgravity conditions to test the viability of expandable space habitats, assess the impact of antibodies on muscle wasting, use protein crystal growth to aid the design of new disease-fighting drugs and investigate how microbes could affect the health of the crew and their equipment over a long duration mission,” said NASA’s Deputy Administrator Dava Newman via a statement issued by the agency.
There’s little doubt that the payload that has “expanded” interest in the mission the most is the Bigelow Expandable Activity Module (BEAM). This technology demonstrator will further studies that have been and are underway into the concept of inflatable habitat modules—something of keen interest to NASA who is hoping to get back into the business of sending astronauts far beyond the orbit of Earth.
In terms of the crew on board the space station, they will spend very little time in BEAM. NASA and Bigelow Aerospace have stated crews will only enter the habitat about three times per year during the its planned two-year stint attached to the outpost. Although it is possible that astronauts on the ISS might spend more time in the hab, at present, they’re only slotted to spend three to four hours in the module during each visit.
As is the case with any research done on orbit, mission planners first have to get their experiments out of Earth’s gravity well. That took place under mostly clear skies which granted a 90 percent chance of favorable conditions for launch.
“The rodents on our experiment will stay on the station for about six weeks, coming back with the CRS-8 Dragon,” NASA Ames Research Center’s Dennis Leveson-Gower told SpaceFlight Insider. “It’s thrilling to see your experiment go up, our team has been really working hard on this […] it’s really exciting to see it go off on the first day that it was scheduled.”
On the afternoon of Thursday, April 7, Dragon was loaded with what is known as “late load” cargo in preparation for the launch attempt.
Some 38 minutes before the launch was scheduled to take place, the launch conductor carried out a readiness poll. This was followed three minutes later with the fueling of the Falcon 9 FT began. The two-stage rocket is fueled by a mixture of RP-1 (a highly refined version of kerosene) and liquid oxygen (LOX). The RP-1 is loaded first, which is then followed about 20 seconds later by the LOX (fueling was completed about a minute-and-a-half before T–0).
With just about 10 minutes remaining before launch, the Falcon 9 FT entered into an engine chill; this was followed about three minutes later by the Dragon spacecraft being switched over to internal power.
Eight minutes later, SpaceX’s Launch Director confirmed that the mission was ready to get underway with the 45th Space Wing’s Range Control Officer verifying that the Eastern Range was ready to support the launch about 30 seconds later.
At just one minute prior to launch, the rocket’s command flight computers began final pre-launch checks. SLC-40’s sound suppression system, dubbed “Niagara”, was activated during this time. Twenty seconds after that, the rocket’s flight tanks were pressurized and the stage was set for flight.
Three seconds before launch, the engine controllers directed the engine ignition sequence to start.
As the new countdown clock in front of the Turn Basin at Kennedy Space Center ticked down to zero, the nine Merlin 1D rocket engines in the Falcon 9 FT’s first stage came alive with fire and thunder—announcing their fury to the residents of the surrounding wetlands.
Just one minute after it had left SLC-40 and the Falcon 9 and Dragon entered the region known as maximum dynamic pressure or “max-Q”—the point where aerodynamic stress on the Falcon 9 is at its maximum.
Three minutes into the flight, the rocket’s first stage had completed its part in the mission and main engine cutoff took place. With its mission complete, staging occurred with the rocket’s first and second stages separating. At this point in the flight, the second stage’s lone Merlin 1D came alive and the nose cone that had shielded Dragon was jettisoned.
Nine minutes after it had left the pad, second engine cutoff or “SECO” took place with the spacecraft separating from the second stage approximately one minute later.
Free of its launch vehicle, Dragon continued on its way, deploying its solar array three minutes after SECO took place. If everything continues apace, at about two hours and twenty minutes after launch, Dragon’s guidance and navigation control bay door will deploy. This will reveal the sensors that will be used on Saturday when the Expedition 47 crew will grapple Dragon and berth it to the ISS.
Before today, SpaceX has only been able to retrieve the first stage once, the December 2015 flight of 11 Orbcomm OG2 satellites. That, however, was a ground landing at Cape Canaveral Air Force Station’s Landing Zone 1 (formerly known as Space Launch Complex 13). Today’s landing was a far more difficult sea landing.
While some launch service providers might rest and review at this point, SpaceX is pressing ahead with a very busy 2016 launch manifest which currently shows as many as twelve more flights—including the inaugural flight of the new Falcon Heavy rocket.
For SpaceX’s CEO and Founder, Elon Musk, practicality and testing new technology need not require separate programs.
“It’s really hard to do these test flights without, actually, going to orbit. We could conceivably, I suppose, put a huge weight, a 120-ton weight on top of the boost stage, and then do these launches, drop the 120-ton weight and then try to land—but there’s no point in that. Why not just send a useful payload while you’re at it, instead of the dead weight,” Musk told SpaceFlight Insider.
That regimen appears to have paid off big time for the NewSpace firm as it has successfully delivered payloads to orbit and demonstrated its ability to land the Falcon 9’s first stage not once, but twice.
Jason Rhian spent several years honing his skills with internships at NASA, the National Space Society and other organizations. He has provided content for outlets such as: Aviation Week & Space Technology, Space.com, The Mars Society and Universe Today.