Wet Dress Rehearsal

Wet Dress Rehearsal Latest News

Recently, NASA found a hydrogen leak during a wet dress rehearsal of its Artemis II mission.

About Wet Dress Rehearsal

• It is the final practice run for a high-stakes rocket launch. 
• The “wet” in the name refers to the loading of cryogenic fuel (typically liquid oxygen and liquid hydrogen for large rockets) into the rocket’s massive tanks.
• It is a rigorous demonstration of ground team preparedness. 
• The team will cool the fuel feed lines, load the tanks, pressurise them, monitor leak detectors, and execute the countdown into its final stages. 
• These rehearsals also keep the tanks full as the propellant warms and boils off, then executes a stop just before ignition, followed by draining and returning the vehicle to a stable configuration. 
• This puts the entire craft through each step of a simulated launch, exposing it to the super-chilled fuels to ensure that everything will function properly on launch day. 
• Wet rehearsals are important because only they can reveal events that happen in cryogenic conditions, e.g., leaks in seals or in the connections between the rocket and ground equipment.

‹ ›

What is a Dry Dress Rehearsal?

• It practices the countdown and important operations without loading cryogenic propellants into the rocket. 
• Instead, the team will power up vehicle and ground systems, verify its communications equipment, simulate critical events, and validate decision-making and handoffs between launch control, engineering, range safety, and, if applicable, crew operations. 
• Many of the testing steps use simulated sensor inputs. 
• These rehearsals are useful to reveal logical problems in the flow of events without risking fuel leaks.

Key Facts about Artemis II Mission

• It is the second scheduled flight of NASA’s Artemis program and the first crewed Artemis mission. 
• It will be the first mission to carry humans to the moon’s vicinity since 1972.
• It is the first to fly astronauts aboard the Space Launch System (SLS) rocket and Orion spacecraft. 
• While Artemis 1 successfully flew Orion around the moon without astronauts in 2022, Artemis 2 will be the first time humans travel aboard the spacecraft and venture beyond Low Earth Orbit in more than 50 years.
• Four astronauts will take a 10-day flight around the moon and back to Earth, testing systems ahead of the Artemis 3 mission, which aims to deliver astronauts to the lunar surface by 2028.
• The mission will include three NASA astronauts and one astronaut from the Canadian Space Agency (CSA).
• The astronauts and mission controllers will collect data on Orion and the crew’s performance to assess how ready the Artemis program is to send people to the moon’s surface.
• Orion will undergo high-speed reentry through Earth’s atmosphere before safely splashing down in the Pacific Ocean off the coast of San Diego.

Source: TH