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SpaceX, NASA Abort Demo-2 Due to Inclement Weather, Next Attempt May 30

SpaceX and NASA aborted the launch of the Demo-2 mission on Wednesday due to inclement weather. The next launch is scheduled for May 30.


SpaceX and NASA were primed to jointly launch the first crewed mission from U.S. soil in nearly a decade today with significant measures in place to shield the mission from the COVID-19 coronavirus crisis.

However the mission — called Demo-2 and set for a 4:33 PM EDT launch via Falcon 9 rocket — was aborted due to inclement weather.

Delayed until May 30, at 3:22 PM EDT, the mission will lift the Crew Dragon into space from Kennedy Space Center in Florida on launchpad 39A — carrying two veteran astronauts. Launchpad 39A carries historic weight, as it hosted several Apollo missions to the moon and most of the Shuttle missions after its construction in the 1960s.


UPDATE May 27, 5:02 PM EDT: Emergency crew escape system disarmed, crew arm moved back into place, Behnken and Hurley disembark

The crew arm was moved back into place and the emergency crew escape system was completely disarmed. This signaled that all of the propellant was removed from the Falcon 9 rocket.

At 5:46 PM EDT, the hatch was opened and the crew began disembarking procedures. 

At 5:53 PM EDT, both astronauts left the Crew Dragon capsule.

UPDATE May 27, 4:50 PM EDT: Why Demo-2 launch was scrubbed amid instantaneous launch window

Today’s launch was scrubbed due to weather, but this was compounded by the fact that it had an instantaneous launch window. This meant that SpaceX couldn’t push the launch time back to wait for the weather to potentially clear later today.

Launch windows often allow for broader variation, but today’s didn’t for several reasons. The launch window depends on the orbital dynamics the craft needs to successfully rendezvous to the ISS. Essentially, if you run calculations for the orbital positions of the Earth and the ISS for today, the only time that allowed for a launch within nominal fuel use parameters for the Falcon 9 was during the minute 4:33 PM EDT. Launching too far outside of that would’ve put the crew and the mission in jeopardy.

We don't yet know what kind of launch window is set for Saturday, but for now the mission is rescheduled for May 30 at 3:22 PM EDT.

UPDATE May 27, 4:33 EDT: Propellants are being removed from Falcon 9; crew waiting for Crew Dragon hatch to open

After the call to abort the launch, crews engaged standard "scrub sequence" procedures to downgrade the rocket from a launch-ready stance. The kerosene and liquid oxygen propellants are at present removed from the rocket. The crew cannot exit until this process is complete due to safety.

The scrub was due to a violation of three launch safety rules: Natural lightning, surface electric field mill rule, and the attached anvil rule, caused by storms in the area related to Tropical Storm Bertha. It should also be noted that weather conditions were expected to clear 10 minutes after the scheduled launch time, at 4:43 PM EDT, but today’s launch window was instantaneous, only allowing a 1-second deviation away from the originally scheduled launch time.

Often, launch windows allow for more deviations that extend to allow for delays after the initially-scheduled launch time. The difference in the type of launch window is due to a variety of conditions that play into exactly how the crew would traverse to the international space station.

UPDATE May 27, 4:18 PM EDT: Due to weather, launch abort proceeds to ‘normal scrub sequence’

Weather has caused SpaceX and NASA to abort the launch of Demo-2 today and it is being moved to May 30. The Falcon and the crew are now beginning to undergo the "normal scrub sequence." The call to abort the launch occurred before fuel was loaded into the second stage of the launch.

Everything from a hardware perspective functioned flawlessly during the flight prep, but weather conditions were just not good enough to risk the lives of Behnken and Hurley.

UPDATE May 27, 4:08 PM EDT: Weather trending toward negative decision

The weather at Cape Canaveral is turning for the worse as the countdown continues, and the crews prepare for launch. A near-final decision is expected in the next five minutes as to whether the countdown for launch may continue without endangering the mission.

UPDATE May 27, 3:47 PM EDT: Propellent begins loading onto Falcon 9, crew access arm retracts

The Demo-2 mission teams are currently taking a launch poll — the launch director will read the poll out at T-minus 45 minutes. This poll is essentially a signal from each engineering and mission team that they're either "go" or "no-go" for launch. However, unlike earlier missions at NASA, we didn't hear an audible checklist performed because the poll is now automated, and activated via computer uplink.

The poll was completed with no issues, and the propellant is presently loading onto the Falcon 9. The launch director is reviewing abort procedures should anything go wrong. The access arm was also retracted from the Dragon capsule.

The propellant is loading onto the first and second stages of the Falcon 9 rocket, and will continue loading so long as all mechanical and technical systems continue to indicate "go for launch." The major concern now is local weather, since conditions at launch are crucial, and the amount of precipitation that occurs before launch can affect the flight. Additionally, if there’s too much precipitation during the loading of the supercooled propellant, ice can build up on the rocket and cause mechanical failures.

The launch escape system has also been armed, which occurs right before fuel is loaded. This gives the crew a way to separate the Dragon capsule from the Falcon 9 in case of emergency.

UPDATE May 27, 3:25 PM EDT: The hatch is closed; 'go for launch'

The closeout crew for the Crew Dragon capsule has departed the pad as the launch team prepares to load the rocket with propellants. A final decision on weather and launch status is expected soon as we are nearing more critical points-of-no-return for launch.

SpaceX has reported no issues with the Falcon 9 rocket as we close in on 60 minutes until launch. The next major event to occur will be the retraction of the crew access walkway, leaving the crew atop the Falcon 9 — where escape becomes complicated.

As of writing, there are several weather factors designated as a "NO-GO," including the surface electric fields, and an attached anvil cloud flight-through-precipitation set of rules. SpaceX and NASA hope weather conditions improve soon. Reports say additional support teams are “go for launch” as scheduled, including a “go for launch” from astronauts Behnken and Hurley.

UPDATE May 27, 3:18 PM EDT: William Shatner, Bill Nye speak on Demo-2 mission

William Shatner — who played Captain Kirk in the science fiction show "Star Trek," spoke during the live-stream to wish the astronauts godspeed and a great flight.

Bill Nye — renowned celebrity scientist and star of "Bill Nye the Science Guy" — also spoke during the broadcast. He urged viewers to consider this mission as the beginning of a new era of commercial space exploration, which he also claimed was great for science.

UPDATE May 27, 3:10 PM EDT: Astronaut interviews and interim before final flight checks and countdown

NASA officials are interviewing several astronauts — some due for future Crew Dragon missions — as the world holds its breath while the countdown ticks forward toward the scheduled launch, still going forward without issues.

One astronaut named Chris Cassidy is the lone American on the International Space Station — and is awaiting his colleagues in LEO.

We are T-minus 1 hour, 25 minutes, and 54 seconds until launch.

UPDATE May 27, 2:48 PM EDT: Air Force One makes flyby of the Demo-2 mission, President Trump arrives to view the launch

Mid-broadcast, spectators saw Air Force One — the U.S. President's private jet — make a flyby of Cape Canaveral on its way to deliver Trump to view the imminent launch of SpaceX and NASA's Demo-2 mission.

UPDATE May 27, 2:45 PM EDT: Inclement weather moves offshore, Crew Dragon hatch closed

Mission control said the inclement weather has begun to move offshore at Cape Canaveral, and the hatch closure happened after additional comms checks between the launch chief engineer and all the subsystem engineers.

This marks the first time that such a comms check was carried out for a SpaceX launch, since no previous launch has featured human passengers.

As of writing, on-site technicians are double-checking O-rings and other devices designed to create a total seal on the Crew Dragon and protect the astronauts from the hazards of outer space.

UPDATE May 27, 2:30 PM EDT: Elon Musk, Jim Bridenstine speak on Demo-2 mission

Administrator of NASA Jim Bridenstine spoke with CEO SpaceX Elon Musk about the Demo-2 mission. Jim noted that SpaceX has been capable of doing things at a speed and rate that NASA was historically never capable of matching.

Musk is the chief engineer of the mission and noted that it's a "dream come true" for him. Musk had doubts that this day would come. He added that when he founded SpaceX in 2002, he thought there was a 90% chance the company would never reach low-Earth orbit (LEO) with a rocket. At this point, the Falcon 9 rocket in its current configuration has flown roughly 20 successful missions. This is the first crewed mission for SpaceX, the gravity of which Musk claims he appreciates.

Bridenstine added that when the government provides both the demand and supply of funding for space missions, innovation is stifled. He underscored that commercial space flight is a new era, one that can bring about a rapid pace of innovation in the industry that NASA couldn't have achieved with U.S. government funding alone.

During the interview, Musk said today's launch is about "getting people fired up about the future — everyone from all walks of life and across the political spectrum should be really excited that this thing is made by humans for humans — it's one of those things that makes you glad to wake up in the morning."

UPDATE May 27, 2:10 PM EDT: Astronauts complete communications check

The crew are strapped into the Crew Dragon capsule and can be heard talking back and forth with mission control. The crews are meticulously checking every communications system for total functionality and performance, to catch potential issues early and before the launch.

After completing the communications system checks, Bob Behnken and Doug Hurley prepared to rotate their seats, and their respective suit technicians have left the capsule.

The crew seats are now rotated upwards so they have a more direct and intuitive view of the touch screen controls.

UPDATE May 27, 1:49 PM EDT: Astronauts board SpaceX Crew Dragon Capsule, tornado warning issued for area

Both astronauts were loaded into the sleek Crew Dragon Capsule as they undergo final checks for launch today. The suit techs are buckling the crew in, hooking up their life-support systems, and otherwise locking Behnken and Hurley into their seats where they will spend the rest of the day.

The umbilical cords were also connected to the crew's spacesuits. These supply fresh and pressurized air, and also feature active communication lines to ground control. The crew dragon can hold up to four astronauts, but today’s first crewed flight will only see two seats occupied.

Inside of the craft, there are three touch screen control boards that the astronauts use without removing their specially-designed SpaceX space gloves. Checkouts of major systems are now complete, including the emergency escape system. There are no current issues and the launch sequence is moving forward as planned.

A tornado warning has been issued for the area by the National Weather Service. NASA has not commented as to how this might affect the launch planned for later in the day.

UPDATE May 27, 1:33 PM EDT: Crew Arrives at launchpad in Tesla Model X vehicles

Astronauts Bob Behnken and Doug Hurley arrived at launch pad 39A after leaving the Operations and Checkout Building. The view of the astronauts exiting the Tesla Model X’s gull-wing doors in SpaceX’s spacesuits felt like science fiction.

The crew listened to AC/DC’s Back in Black, the elevator music from the Blues Brothers, and a few other songs on their drive to the pad.

Both astronauts have taken the elevator 77 meters (255 feet) into the air — to the top of the crew platform — as they prepare to load into the Crew Dragon capsule.

UPDATE May 27, 1:14 PM EDT: Bob Behnken and Doug Hurley wave goodbye to their family, board Model X transport vehicles

Both astronauts have waved goodbye to their wives and children, all from a distance due to the COVID-19 quarantine. They have now boarded the Model X transport SUVs fully donned in their SpaceX flight suits. Now begins a 20-minute ride to the launch pad.

UPDATE May 27, 1:12 PM EDT: Elon Musk and Vice President Pence wait by Two Model X’s ready to transport the Demo-2 crew

Two Tesla Model X SUVs adorned in NASA logos are standing ready to pick up astronauts Bob Behnken and Doug Hurley as they say their final goodbyes before the launch.

UPDATE May 27, 1:09 PM EDT: Kelly Clarkson sings the US National Anthem virtually on livestream

Thanks to COVID-19 restrictions, the events surrounding the Demo-2 launch are all virtual. Kelly Clarkson was selected to sing the U.S. National Anthem today, from her home.

UPDATE May 27, 1:03 PM EDT: No issues with launch, flight plan still go for 4:33 PM EDT

Weather is clearing up at the launch complex and the SpaceX team is beginning the process of loading fuel into the rocket. Weather balloons have been launched that will give a better idea of upper atmospheric weather for launch. So far, hopes are improving for the weather holding out this afternoon.

UPDATE May 27, 12:53 PM EDT: Spacesuit checks are complete and Musk visits astronauts

SpaceX is reporting that the suits have passed their leak check. Elon Musk is currently speaking with the astronauts before they begin their journey to the launch pad. 

UPDATE May 27, 12:42 PM EDT: Astronauts are suited up in futuristic SpaceX suits in the Neil Armstrong Operations and Checkout Building

Both astronauts for the Demo-2 mission have completely suited up in the Neil Armstrong Operations and Checkout Building at the Kennedy Space Center in Florida. The suits are being checked for leaks. The suits will be worn during launch and re-entry to provide a safe pressurized environment.

UPDATE May 27, 12:34 PM EDT: Crew arrive in suit-up room, conditions look acceptable for flight

Astronauts Bob Behnken and Doug Hurley just left their initial weather briefing for the day and have been moved to the suit-up room to begin the initial stages of suiting-up for launch. The launch team is monitoring the Falcon 9 rocket and noted no issues with the flight plan.

The tropical storm has started moving onto shore and conditions are slowly improving at the launch pad.

UPDATE May 27, 12:28 PM EDT: Use the hashtag #LaunchAmerica to ask live NASA questions

Using the hashtag #LaunchAmerica on Twitter, users can ask questions to NASA during its live-stream today. They plan on doing Q&A periods during the stream to engage with users. They also have live polls and tweets on the NASA Twitter account.

UPDATE May 27, 12:20 PM EDT: Weather concerns cast shadow on SpaceX, NASA launch

Hopes are high for the launch on Wednesday, with weather forecasters closely monitoring the formation of a tropical storm off the coast of South Carolina. The US Air Force reports a 50% chance of inclement weather scrubbing the launch. If this happens, SpaceX will try again on May 30.

UPDATE May 27, 12:23 PM EDT: Weather experts are closely evaluating conditions around the launchpad

Tropical storm Bertha could cause NASA and SpaceX to postpone the launch until May 30th, but hopes are still high. Experts say there is a 50/50 chance that the launch will get scrubbed today. That said, the cloudy skies and adverse weather around Cape Canaveral are expected to clear soon.

SpaceX, NASA to launch astronauts from US soil

This will be the first crewed launch into space from U.S. soil since the end of the space shuttle program in 2011. Demo-2 will be manned by Bob Behnken and Doug Hurley, where they will ride on a roughly 19-hour journey to dock with the International Space Station (ISS).

This launch is a major benchmark for both SpaceX and NASA. In essence, we're about to see capabilities of the Crew Dragon capsule and the Falcon 9 reusable rocket system legitimized for human spaceflight. NASA has stressed that in all practicality, the Demo-2 mission is a test flight manned by two expert pilots.

Notably, the U.S. President is scheduled to attend the launch on Wednesday, according to a tweet from Atlantic writer Marina Koren.

After a successful launch, NASA plans to accelerate its space-flight program and partnership with SpaceX.

The end of a Russia-dependent era

This launch will also mark the end of American dependence on Russian craft. Since the end of the Shuttle program, NASA has paid Russia for seats on their Soyuz spacecraft missions — which run upwards of an estimated $86 million per seat.

Additionally, this is the first crewed launch of a new orbital craft since 1981 when the shuttle was first launched. Crew Dragon will go down as the ninth vehicle in world history to carry astronauts into orbit.

President Trump is set to attend the launch to witness the rebirth of crewed U.S.-launched space missions in Cape Canaveral today too, according to a tweet.

Astronauts Bob Behnken and Doug Hurley

Both astronauts set to launch today on the Demo-2 mission are seasoned NASA astronauts. Robert "Bob" Behnken is the former chief of the astronaut office, holds a doctorate in mechanical engineering, and flew aboard shuttle missions in 2008 and 2010. Bob has logged a total of 708 hours in space and 37 hours of spacewalk time.

Doug Hurley is a Marine Corps pilot  and engineer who has piloted two shuttle missions — one in 2009 and one in 2011, the final flight of the shuttle program. He is in command of the Crew Dragon Demo-2 mission, which will restart manned launches from U.S. soil. Notably, aside from his accolades working with NASA, he was the first Marine pilot to fly the F/A-18 E/F Super Hornet.