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SpaceX explains why his space ship "Crew Dragon" exploded in April



  • SpaceX's new spacecraft for NASA's astronauts explodes during a terrain in Florida on April 20th. No one was hurt.
  • The seven-pound capsule called the Crew Dragon exploded due to a valve problem, SpaceX's director Hans Koenigsmann said on Monday.
  • Konigsmann said the investigation was "80% done" and added that he was unsure whether Crew Dragon would start with astronauts before the end of the year. An official NASA official called the discovery of the "huge gift for us" problem in terms of making the ship safer.
  • Visit the Business Insider homepage for more stories.

SpaceX believes he can understand what caused his new space ship, Dragon Crew, to explode during a test on April 20th.

The Capsule-like ship is designed to carry NASA astronauts to and from the International Space Station, but first have to pass a series of major tests.

In April, SpaceX conducted a ground test, which was a warm-up to a rocket break test. The interruption test is designed to prove that space evacuation ships can find cosmonauts for safety (in case there is a missile problem).

But instead of showing that the push pushers are working normally, the procedure sends clouds of harmful pink smoke rising in the air over Cape Canaveral, Florida.

SpaceX called the "anomaly" incident on the day it happened, and the next day a video showed up on the Dragon Crew that exploded on the test site. In May, Hans Koenigsmann, SpaceX's mission statement assistant, confirmed that the test really destroyed the company's ship.

Now, almost three months after the accidental blast, Konigsmann said the investigators are about 80% of their work and believe they have discovered what happened.

"We know we had a missing component in the system," Koenigsmann told reporters at a teleconference on Monday. This "triggered a violent reaction" after the escape system was activated, he added.

NASA's Cathy Luders also joined the press conference on Monday. She runs the agency's commercial agency program through which SpaceX is paid to develop, build and test the Crew Dragon.

"In many ways, it was a gift to us because it was a test on the ground," Lueders said. "We had the potential to find a hardware problem and find the hardware and appreciate the hardware."

What SpaceX believes the seepage valve has destroyed the crew ship of Dragon's Crew Dragon

SpaceX crew spacecraft on a restocking boat after returning to Earth on March 8, 2019.
A NASA TV

In March, the Drak Crew Capsule came out in orbit hanging from the space station and returned to Earth. The mission was one of several uncompleted demonstration tests that NASA requires. SpaceX then recovers the car from the ocean, checks it and refreshes it.

Leading to the next company event, his flight break test initially planned for the summer, SpaceX workers fixed the refitted test rig capsule. The test had two stages. The first is to launch low-pressure engines called Dragos to show they can maneuver the capsule in space. The next is a test launch of high-pressure engines called the Super Dracos that power the space ship escape system. The smaller Draco engines shot for about five seconds, and Konigsmann said the test was successful. However, the entire hell disappeared when the spacecraft began to exert pressure on its Super Draco system.

SpaceX, NASA, the US Air Force and other investigating team members spent weeks collecting the Dragon's crew. They also looked at the data from spacecraft and played high-speed videos in search of a cause.

Koenigsman revealed on Monday that investigators have detected traces of burning in the pressure boosting system valves: a component designed to hold the liquid oxidant until the system can shoot it in the engines at the right speed. The explosion coincided with the activation of the system, he added. The best experience of the researchers at this point, says SpaceX, is that during the processing of the spacecraft used, the "mica" of the Super Dragon Oxidant – a toxic substance called nitrogen tetroxide – passes through the return valve and in the pressure boosting pipes.

When this system switched on, it almost instantly rotated the pressure to 2300 pounds per square inch (more than 150 times the normal sea-level air pressure). At that moment, the liquid sluice shifted to the safety valve like a bullet. "It basically destroyed the valve and triggered an explosion," Koenigsmann said. "This effect was not expected."

The Super Dragon is used for spacecraft crew of the SpaceX spacecraft as part of the escape system. Although the investigation continues, Konigsmann said the planned replacement of the non-return valve – which can be switched on and off – with a "blast valve" which opens one-way under high pressure. The lifting valve will not allow any leaks, he said, but the component is more difficult to test because it is a one-time use. (The attempt to test many other valves produced in the same batch.)

SpaceX hoped to release its first astronauts by the end of the year, but Coenigman expressed doubts about keeping this schedule. "We will fly when we are ready," he said.

SpaceX and NASA did not respond immediately to further questions about the failure and its plan to re-test engine evacuation engines after repair.

What else did SpaceX say about the crew explosion of the dragon

Below is the full and detailed statement of SpaceX on the matter:

On Saturday, April 20, 2019 at 6:13 pm UTC, SpaceX held a series from static fire engines testing the tested vehicle on a dragon during a flight on a test rig at SpaceX's Landing Zone 1, the Cape Canaveral Air Force in Florida.

The Crew Dragon design incorporates two different propulsion systems – a low pressure propulsion system with six Draco orbital drives and a high pressure propulsion system with eight SuperDraco engines for use only in the event of a launch escape. Following the successful demonstration mission of the vehicle to and from the International Space Station in March 2019, SpaceX performed additional tests on the vehicle propulsion systems to ensure functionality and detect any system-level problems before the planned flight disruption test.

Initial tests of the twelve Draco engines on the car have been successful, but the initial test of eight SuperDraco pushers led to vehicle destruction. In accordance with pre-established safety protocols, the test area was clear and the team monitored winds and other factors to ensure public health and safety.

After an anomaly, SpaceX called an Accident Investigation Team, including NASA and FAA observers and NTSB, and began systematic work on a complete tree of errors to determine the probable cause. SpaceX also works closely with the US Air Force (USAF) to protect the test site and collect and clean the debris as part of the investigation. The site was operational before launching STP-2 into SpaceX's Falcon Heavy and landing of two first-stage booster blasts in landing zones 1 and 2 on June 25, 2019.

The initial data from the data show that the anomaly has occurred approximately 100 milliseconds before the eight SuperDraco pushers of the Crew Dragon are launched and during the sealing of the vehicle propulsion systems. Evidence shows that a leak component allows a liquid oxidant – nitrogen oxides (NTO) – to enter high pressure helium pipes during ground treatment. The hose from this NTO was propelled by a high-velocity helix valve during a quick initialisation of the escape system, resulting in structural damage to the return valve. The failure of a titanium component in a high pressure NTO environment was sufficient to ignite the check valve and lead to an explosion.

In order to understand the exact scenario and characterize the flammability of the internal components of the titanium valve of the control valve and the NTO and other materials used in the system, the accident investigation team carried out a series of tests at the SpaceX rocket launcher at McGregor , Texas. The debris collected by the Florida test site, which identified the burn-back in the valve, informed the tests in Texas. In addition, the SuperDraco engines recovered from the test site remained intact, emphasizing their reliability.

It is worth noting that the reaction between titanium and NTO at high pressure is not expected. Titan has been safely used for many decades and many spacecraft from all over the world. However, the static fire test and the anomaly provided many data. The lessons learned – and others in our overall test campaign – will lead to further improvements in the safety and reliability of SpaceX's aircraft.

SpaceX has already initiated several actions by eliminating each flow path in the liquid propellant discharge system to enter the gas pressure system. Instead of reversing valves, which usually allow the fluid to flow in just one direction, bursting discs that seal completely while opening from high pressure will completely reduce the risk. Comprehensive testing and analysis of these mitigations have already begun in close coordination with NASA and will be completed before future flights.

With multiple vehicles from the Dragon crew in various production and testing phases, SpaceX transferred the spacecraft tasks forward to stay on the runway for the Commercial Crew Program flight. The Dragon Crew Spacecraft, originally assigned to Demo-2's second SpaceX Demo SpaceX demonstration mission, will perform the company's flight break test and the spacecraft initially assigned to the first operational mission (crew-1) will start as part of Demo-2.


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