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Almost done: SpaceX still has to work before Dragon is ready for the crew



This article originally appeared in the SpaceNews magazine's March 11, 2019 issue.

Among the thousands of spectators watching the Falcon 9 launch the first Crew Dragon spacecraft in the early hours of March of Kennedy Space Center out watched 2, few had a greater interest in the mission than Bob Behnken and Doug Hurley. The two experienced NASA astronauts with four shuttle flights have been part of the commercial crew program in recent years, working with Boeing and SpaceX to design and operate their vehicles.

The two were particularly interested This demo-1 launch is the crew of the next crew Dragon mission, Demo-2, which will be held in July. The two followed the launch of a refurbished launch control center in the Apollo era at KSC and then, 24 hours later, SpaceX's mission control at its Hawthorne, California headquarters to watch as the spacecraft approached and docked with the International Space Station

The two had to please what they saw. Crew Dragon made it into orbit after a smooth start from the historic KSC Launch Complex 39A. The spaceship approached the station a day later and connected to the Station's Harmony module about 1

5 minutes ahead of schedule.

"We have been following this process for several years at this point," Behnken said at one point. Start press conference at KSC. "Seeing such a success like this definitely gives us a lot of confidence for the future."

"It seemed like everything went smoothly," added Hurley. "From our point of view, you want to see this. They want to see how the team makes its way.

  NASA astronauts Doug Hurley (left) and Bob Behnken (right), who are to fly with the manned Demo 2 mission, are watching the launch of a SpaceX Falcon 9 on March 2, launching the Crew Dragon The company's Spaceship for the Demo 1 mission, from the Launch Control Center at the Kennedy Space Center. Photo credits: NASA / Joel Kowsky
NASA astronauts Doug Hurley (left) and Bob Behnken (right), who are to fly with the manned Demo 2 mission, watch the launch of a SpaceX Falcon 9 rocket on 2. March, the company's crew carries Dragon Spacecraft on the Demo 1 mission from the Launch Control Center at the Kennedy Space Center. Credit: NASA / Joel Kowsky

The demo-1 mission ended on March 8 with a successful disconnection from the ISS, followed six hours later by the Atlantic Ocean off the coast of Florida with SpaceX's rescue vessels. The final stages of the mission seemed to be as smooth as the rest of the flight.

"I can not believe how well the whole mission went," said Benji Reed, director of commercial crew mission management at SpaceX, in an interview on NASA TV shortly after the splash.

More to do

Even though the recovery and post-flight inspections are as smooth as take-off and docking, that does not mean that Crew Dragon is ready for Behnken and Hurley to board the ship before they leave NASA officials said that work had already been identified before the demo-1 flight that needed to be done before the agency was allowed to fly astronauts aboard.

"There are two drivers" for this additional work, Kathy Lueders, manager of NASA's commercial crew program, said at a briefing. Part of this work includes systems that are not needed for the Demo 1 mission because there is no crew on board. For example, the spacecraft did not have a comprehensive life support system on board, but a scaled-down version designed to collect test data.

Another system that is not needed for Demo-1 are the displays and interfaces that astronaut flying spaceship would use. "Obviously, you do not need crew interfaces unless Ripley is flying by plane," she said, referring to the mannequin aboard the spacecraft, which is equipped with instruments to measure the environment astronauts experience on the spacecraft would.

Other work concerns problems testing the demo 1 spacecraft, which are not enough to delay the launch, but need to be corrected before demo-2. "The second piece is the stuff we've found in the last six to nine months, and after the capsule is basically done, we apply that knowledge to the Demo 2 vehicle," she said.

One such issue concerns the Draco power Crew Dragon. In the spacecraft's thermal vacuum test, engineers found that temperatures could be so low that the fuel lines would not freeze. "For the entire environment that we expected to run this mission within this mission, the Dracos did not like the environment. They did not work well in this environment, "Lueders said.

  A Falcon 9 rocket crewed by Crew Dragon takes off from the Launch Complex 39A at 2:49 am on March 2 at Kennedy Space Center. Credit: SpaceX
A Falcon 9 rocket crew Dragon is carrying will lift off from Launch Complex 39A at Kennedy Space Center at 2:49 am Eastern Time on March 2. Credit: SpaceX

The solution for Demo-1 was to limit the mission design so that it was unlikely that the spacecraft could get cold until the lines freeze – this only had to be started on days when Crew Dragon was launched within a day of launch If the launch was scrubbed on March 2 due to weather or technical reasons, the next launch window was not until March 5. The permanent solution to be implemented on the Demo 2 and the later Crew Dragon spaceship , it is best to install heaters in the LPG piping

Depending on the analysis of data collected during the flight, further corrections may be required for Crew Dragon. "I would not be surprised if that happens," said Hans Koenigsmann, vice president of construction and flight safety at SpaceX. "This is a test flight, so we will learn something and gain experience with our subsystems."

Timing Between Balance and Safety

NASA's recent public commercial schedule for the commercial occupation program envisages that Demo-2 will take place the earliest in July, one month after a crew test of the Crew Dragon demolition system, using the same capsule like Demo-1. Koenigsmann said that even though there are changes that need to be made to the spacecraft, it may still be possible to fly the mission this summer.

"There's really a lot of ingenuity in both teams," he said of NASA and SpaceX, referring to changing the mission profile for demo 1 as an example. "If it's like that, I'd expect to find a similar operational solution."

However, NASA officials were not nearly as optimistic. Although they did not provide accurate data, they suggested they could rely on Crew Dragon later in the year before NASA astronauts.

  SpaceX chief Elon Musk, left, NASA astronaut Victor Glover, Doug Hurley, Bob Behnken NASA administrator Jim Bridenstine and NASA astronaut Mike Hopkins are about to launch Demo-1 during the launch of the Launch Complex 39A -Mission early Saturday morning to see the crew's arm. Credit: NASA / Joel Kowsky
SpaceX chief Elon Musk, left, NASA astronauts Victor Glover, Doug Hurley, Bob Behnken, NASA administrator Jim Bridenstine and NASA astronaut Mike Hopkins are in the crew with the SpaceX Crew Dragon spacecraft Crew Watching You will be visible during a tour of Launch Complex 39A before launching the Demo 1 mission on Saturday morning. Credit: NASA / Joel Kowsky

Being at the start of Demo 1 was exciting, said Pat Forrester, head of NASA's astronaut corps. "But it will be more exciting when we come back to Demo-2," he said. "Although much progress has been made, much remains to be done, and we look forward to working with SpaceX as a team to accomplish that."

"There are some questions we are working through," Crew Dragon said Mark Geyer, Director of the Johnson Space Center. "We'll start when we're ready, and it might be a bit, but none of it is insurmountable."

When NASA awarded commercial contracts to crews in September 2014, the agency set itself the goal of having both crews. The CST-100 Starliner of Dragon and Boeing was certified to carry passengers by the end of 2017, an appointment that two years before NASA's original schedule for the 2010 program had dropped. There are doubts even with the success of Demo 1. There are doubts that both companies – Boeing's test flights one month behind SpaceX's public NASA schedules – will be certified by the end of 2019.

Such delays are common for large NASA programs, from the James Webb Space Telescope to Space Launch, Endemic System, and Orion. One complicating factor, however, is that NASA's access to Soyuz seats is exhausted by the end of this year, jeopardizing its ability to maintain an American presence on the station.

On February 13, NASA issued a notice announcing its intention to acquire two Soyuz seats from the Russian space company Roscosmos. One seat would be on a mission this autumn, the other in spring 2020 to ensure station presence next September, regardless of the crew members' status. Seating was available, Agency sources said, as Roscosmos did not plan to fill in the crew of three station crew members due to ongoing delays in introducing new Russian modules.

The seats give NASA, Boeing and SpaceX some breathing room. "What we do not want is for the teams to feel under pressure, to fly those things when we're not ready," Geyer said. "The purchase of these additional seats gives us the assurance of having Americans aboard the space station."

Another option that NASA had announced last year is to turn the Starliner test flight into a long flight lasting up to six months. (There are no plans for the Demo 2 mission that will be docked at the station for no more than a month.) The three-person crew for this mission, which includes former NASA astronaut Chris Ferguson, is now working for Boeing was trained for a longer stay.

NASA Administrator Jim Bridenstine, however, said prior to the launch of Demo 1 that NASA had not yet decided on the duration of this Boeing mission. "As things get closer, we will be able to assess what the needs are, and we will make findings based on those needs," he said. "I currently have no timeline."

  SpaceX plans to reuse the demo-1 Crew Dragon capsule pictured above in January for a test of the vehicle's onboard board system before the flight crewed demo 2 mission only in July. Credit: SpaceX
SpaceX plans to use the demo-1 Crew Dragon capsule, shown in January, for a test of the vehicle's board crash system during the flight, before the occupied Demo 2 mission departed in July becomes. Credit: SpaceX

This decision to buy Soyuz seats is a relief to the Aerospace Safety Advisory Panel. In his most recent annual report, released on February 8, he warned against time pressure and urged NASA and Congress to develop a "climate change plan designed to ensure continued US presence on the ISS until commercial crew providers be available." a lot of groundwork that both must complete, "said Sandy Magnus, a former astronaut and member of the panel, at his last public meeting on March 7 at the KSC. "We are not ready to put people in a vehicle yet. We are pleased that NASA has taken steps to ensure the continuation of the US presence on the ISS, and this continues to diminish perceived deadline pressure.

The demo 2 crew is just ready to wait and fly the spaceship is ready. "I think they would admit that they will have more work to do in preparation for the demo-2 flight we will be attending," Behnken said before launching SpaceX's demo-1. "I think as a team we would all agree that we're probably not ready for the Demo 2 mission."

But with the demo-1 mission now in the books, they're almost done.


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