At Kennedy Space Center’s Launch Complex 39A, valves are open and propellants are beginning to flow into the SpaceX Falcon 9 rocket. Atop the rocket is the SpaceX Crew Dragon spacecraft, with two NASA astronauts – Robert Behnken and Douglas Hurley – safely strapped inside.
Liftoff on NASA’s SpaceX Demo-2 mission to the International Space Station remains planned for an instantaneous launch window at 3:22 p.m. EDT.
NASA’s SpaceX Demo-2 astronauts Robert Behnken and Douglas Hurley have been given the “go” to close their visors and arm the Crew Dragon’s launch escape system (LES). The crew access arm has been retracted.
Consisting of a set of eight SuperDraco engines integrated into the spacecraft’s body, the LES is designed to separate the spacecraft from the Falcon 9 rocket and carry the crew away to safety in the unlikely event of an emergency.
The system was tested during January’s uncrewed In-Flight Abort Test to show the Crew Dragon’s capability to safely separate from the Falcon 9 rocket. For that test, SpaceX configured Crew Dragon to trigger a launch escape about a minute and a half after liftoff. All major functions were performed, including separation, engine firings, parachute deployment and landing. Crew Dragon splashed down just off the Florida coast in the Atlantic Ocean.
The SpaceX Demo-2 crew, astronauts Robert Behnken and Douglas Hurley, were just informed that weather is currently “go,” with an upgraded forecast predicting a 70% chance of good weather at the 3:22 p.m. EDT launch time.
The launch team just verified controllers are “go” to begin loading propellants – liquid oxygen and a refined, rocket-grade kerosene called RP-1 – into the Falcon 9 rocket’s first and second stages.
With about an hour and five minutes remaining until today’s 3:22 p.m. EDT liftoff time, SpaceX Demo-2 launch countdown is proceeding according to schedule at NASA’s Kennedy Space Center in Florida. A weather update is coming up; although rain in the launch area has let up, some conditions are still “no go,” including lightning, cumulus clouds and electric fields.
Here’s a look at some of the major milestones still to come. (Times are shown in “L-time” – minutes and seconds prior to launch time.)
-45:00 SpaceX Launch Director verifies “go” for propellant load
-42:00 Crew access arm retracts
-37:00 Dragon launch escape system is armed
-35:00 RP-1 (rocket grade kerosene) loading begins
-35:00 1st stage LOX (liquid oxygen) loading begins
-16:00 2nd stage LOX loading begins
-07:00 Falcon 9 begins engine chill prior to launch
-05:00 Dragon transitions to internal power
-01:00 Command flight computer to begin final prelaunch checks
-01:00 Propellant tank pressurization to flight pressure begins
-00:45 SpaceX Launch Director verifies “go” for launch
-00:03 Engine controller commands engine ignition sequence to start
-00:00 Falcon 9 liftoff
Several NASA and SpaceX teams across the country have roles in today’s launch. SpaceX’s launch team is commanding the countdown from Firing Room 4 in Kennedy’s Launch Control Center, then will transfer control to the company’s mission control center in Hawthorne, California. Meanwhile, NASA teams at Kennedy and the agency’s Johnson Space Center in Houston are monitoring today’s activities.
Liftoff of the SpaceX Falcon 9 rocket and Crew Dragon spacecraft carrying NASA astronauts Robert Behnken and Douglas Hurley remains scheduled for 3:22 p.m. EDT – an instantaneous launch opportunity. The crew is already strapped into the spacecraft at Kennedy’s Launch Complex 39A. The launch team continues to closely monitor the weather, which has a 50-50 chance of cooperating at launch time according to meteorologists with the U.S. Air Force 45th Weather Squadron.
NASA’s SpaceX Demo-2 mission to the International Space Station will serve as an end-to-end flight test to validate the SpaceX crew transportation system, from launch to docking to splashdown. It is the final flight test for the system to be certified for regular crew flights to the station as part of NASA’s Commercial Crew Program.
Weather is “no go” for now, but meteorologists predict there could be a clearing in the rain later in the countdown. The next decision point for the launch team will be prior to propellant loading operations, which will begin at about 2:47 p.m. EDT or about 35 minutes prior to launch.
NASA’s SpaceX Demo-2 mission is targeted to launch today at 3:22 p.m. EDT. At that time, the International Space Station will be flying at an altitude of 259 statute miles over the Atlantic off the coast of North Carolina.
The Demo-2 mission will serve as an end-to-end flight test to validate the SpaceX crew transportation system, from launch to docking to splashdown. It is the final flight test for the system to be certified for regular crew flights to the station as part of NASA’s Commercial Crew Program.
The hatch through which NASA’s SpaceX Demo-2 crew members entered the Crew Dragon spacecraft has been closed and a leak check is complete. Launch of the SpaceX Falcon 9 rocket and Crew Dragon spacecraft carrying NASA astronauts Robert Behnken and Douglas Hurley remains scheduled for 3:22 p.m. EDT from Kennedy Space Center’s Launch Complex 39A. Teams continue to monitor weather conditions throughout the area; there are showers popping up in the area, but the team is proceeding with the count. The next decision point will come prior to the loading of the rocket’s propellants.
NASA’s SpaceX Demo-2 mission will serve as an end-to-end flight test to validate the SpaceX crew transportation system, from launch to docking to splashdown. It is the final flight test for the system to be certified for regular crew flights to the station as part of NASA’s Commercial Crew Program.
The two-stage SpaceX Falcon 9 rocket has flown 83 times for NASA and other customers. The vehicle made history in 2012 when it delivered Dragon into the correct orbit for rendezvous with the International Space Station, making SpaceX the first commercial company to visit the station. Since then, Falcon 9 has made numerous trips to space, delivering satellites to orbit as well as delivering and returning cargo from the space station for NASA. Click here to see a labeled Falcon 9 illustration.
Falcon 9, along with the Dragon spacecraft, was designed from the outset to deliver humans into space, a goal on the cusp of being achieved.
Falcon 9’s first stage incorporates nine Merlin engines and aluminum-lithium alloy tanks containing liquid oxygen (LOX) and rocket-grade kerosene (RP-1) propellant. Falcon 9 generates more than 1.7 million pounds of thrust at sea level but produces over 1.8 million pounds of thrust in the vacuum of space. The first-stage engines are gradually throttled near the end of first-stage flight to limit launch vehicle acceleration as the rocket’s mass decreases with the burning of fuel.
The rocket’s second stage relies on a single Merlin engine that also runs on LOX and RP-1.
Technical Overview
Height: 70 meters or 229.6 feet
Mass: 549,054 kilograms or 1,207,920 pounds
Payload to Low Earth Orbit: 22,800 kilograms or 50,265 pounds
Diameter: 3.7 meters or 12 feet
The Falcon 9 is the first orbital class rocket capable of reflight, and today, the first-stage booster will aim for a vertical landing on a SpaceX drone ship called “Of Course I Still Love You,” which is waiting offshore in the Atlantic.
The seats inside the SpaceX Crew Dragon spacecraft have been rotated into position for today’s launch. NASA astronauts Douglas Hurley and Robert Behnken are now in a reclining position, with their backs nearly parallel with the ground and with easy access to their spacecraft displays.