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9 hours and 30 minutes. Still on track for a launch.
NASA coverage will start about 4 hours before launch.
NASA coverage will start about 4 hours before launch.
Helium serves several important purposes in rockets:
Overall, helium plays a crucial role in ensuring the safe and efficient operation of rocket propulsion systems.
- Pressurization: Helium is commonly used to pressurize the propellant tanks in rockets. As the rocket burns fuel and the propellant tanks empty, helium is injected into the tanks to maintain the necessary pressure for propellant flow.
- Purging: Helium is also used to purge and inert the fuel and oxidizer lines in rockets, preventing the formation of potentially explosive mixtures of fuel and oxidizer gases.
- Cooling: In some rocket systems, helium is used as a coolant for various components, such as the engine nozzles, to prevent overheating during operation.
- Gas generators: Helium is sometimes employed in gas generators, which provide the energy needed to drive turbopumps that feed fuel and oxidizer into the rocket's combustion chamber.
I’ve never heard of helium being used to drive turbines or cool nozzles. You’re leaving performance on the table that way, and helium isn’t a very good coolant compared to your fuel, whether it be hydrogen, methane, kerosene, or hydrazine derivatives.Borg said:According to ChatGPT:
May 22 (UPI) -- Boeing's Starliner manned Crew Flight test has been indefinitely delayed after a string of issues, NASA officials said.
The launch has been scheduled for no earlier than Saturday, and no new date has been announced.
Yes, if for no other reason than to finish the contract to prove it out. After that? Probably not. Too expensive to launch it compared to Dragon.gleem said:Will Starliner ever get off the ground? Seven years and holding.
CNN —
The latest attempt at an inaugural crewed launch of Boeing’s Starliner spacecraft is on track for Wednesday after a computer issue halted the countdown just moments before liftoff on Saturday.
The historic mission, called the Crew Flight Test, is set to launch at 10:52 a.m. ET from Cape Canaveral Space Force Station in Florida. The event will stream live on NASA’s website, with coverage beginning at 6:45 a.m. ET.
United Launch Alliance technicians and engineers assessed the ground support equipment over the weekend, examining three large computers housed inside a shelter at the base of the launchpad. Each computer is the same, providing triple redundancy to ensure the safe launch of crewed missions.
“Imagine a large rack that is a big computer where the functions of the computer as a controller are broken up separately into individual cards or printed wire circuit boards,” said Tory Bruno, president and CEO of United Launch Alliance, during a Saturday news conference. “They’re all stand-alone, but together, it’s an integrated controller.”
The cards within the computers are responsible for different key systems that must occur before a launch, such as releasing bolts at the rocket’s base so it can lift off after ignition.
During the final four minutes before launch, all three computers must communicate and agree with one another. But during Saturday’s countdown, a card on one of the computers was six seconds slower in responding than the other two computers, indicating that something was not correct and triggering an automatic hold, according to Bruno.
Over the weekend, engineers evaluated the computers, their power supply and network communications between the computers. The team isolated the issue to a single ground power supply within one of the computers, which provides power to the computer cards responsible for key countdown events — including the replenishment valves for the rocket’s upper stage, according to an update shared by NASA.
Starliner teams reported no signs of physical damage to the computer, which they removed and replaced with a spare. Meanwhile, mission specialists continue to analyze the faulty power unit to better understand what went wrong.
The other computers and their cards were also assessed, and all of them are performing normally as expected, according to the ULA team.
The Starliner mission management team reviewed the computer replacement troubleshooting steps that were taken, and they have agreed that Starliner is “go” for launch on Wednesday, according to an update from NASA.
“I really appreciate all the work by the NASA, Boeing, and ULA teams over the last week,” said Steve Stich, manager of NASA’s Commercial Crew Program, in a statement. “In particular, the ULA team worked really hard to quickly learn more about these issues, keep our NASA and Boeing teams informed, and protect for this next attempt. We will continue to take it one step at a time.”
Didn't Gemini VI and Gemini VII, each carrying two US astronauts, rendezvous in orbit back in 1965?mfb said:First time two different crewed US spacecraft are in orbit at the same time.
I think he means different designs. Dragon and Starlinerrenormalize said:Didn't Gemini VI and Gemini VII, each carrying two US astronauts, rendezvous in orbit back in 1965?
Boeing’s Starliner mission has safely docked with the International Space Station and the spacecraft’s crew, NASA astronauts Butch Wilmore and Suni Williams, have arrived aboard the station after navigating new issues that cropped up overnight and Thursday en route to the orbiting laboratory.
This is the first time astronauts have arrived at the space station from a Boeing Starliner spacecraft.
Docking occurred at 1:34 p.m. ET. Steps were taken to more firmly secure the connection between Starliner and the space station’s port, and docking was completed about 20 minutes later.
My immediate thought was, "You gotta show me that". With Elon's reputation, you had to believe he could make it work - but still ... like a steam iron?On the windward side, what I want to do is have the first-ever regenerative heat shield. A double-walled stainless shell—like a stainless-steel sandwich, essentially, with two layers. You just need, essentially, two layers that are joined with stringers. You flow either fuel or water in between the sandwich layer, and then you have micro-perforations on the outside—very tiny perforations—and you essentially bleed water, or you could bleed fuel, through the micro-perforations on the outside. You wouldn’t see them unless you got up close. But you use transpiration cooling to cool the windward side of the rocket. So the whole thing will still look fully chrome, like this cocktail shaker in front of us. But one side will be double-walled and that serves a double purpose, which is to stiffen the structure of the vehicle so it does not suffer from the fate of the Atlas. You have a heat shield that serves double duty as structure.