Mark Nappi, vice president of Boeing's Commercial Crew Program, added, "We have an incredible opportunity to spend more time at station and perform more tests which provides invaluable data unique to our position."
Weird they just didn't plan for this incredible opportunity from the start but sounds like they are just taking extra time as an opportunity not because they need to evaluate any safety issues (at least per Boeing).
Let's hope it safely returns home, it is becoming quite risky to give legacy makers contracts anymore even ULA which has a good track record of safety is has many tasks being delayed.
I think delays, within reason, are not an issue. Delays are very common in spaceflight. As long as they're delivering a high quality product for a decent price, some delays are acceptable. So far, I think ULA has been within reason on that front.
> Can't wait for them to declare that starliner is actually the newest ISS module and it ain't coming back.
I know that's probably a joke, but that would be incredible bad for NASA. There is already strong competition for access to docking ports on the ISS. Losing one would badly complicated logistics on the station.
If the leaks indicate COPV compromise, it could eventually rupture, causing potentially serious damage -- especially if hypergolic fuel tanks are ruptured in the process.
On the other hand, if the leaks are at the manifold then starliner might become an ISS module indeed, but taking up an airlock is bad news nonetheless so they would still have to find a way to jettison it.
I'm waiting for the pics of the upcoming space walk where the astronauts have Starliner up on blocks with the hood open. Maybe another shot of them with crowbars trying to manually pry it off the station.
Every single person at Boeing should be full of shame at this entire process. The thing is an utter joke to everyone.
How many docking ports are on the ISS? Maybe this is Boeing's way of slowing down Dragon capsule dockings? Or maybe this will be their Apollo 13 version of a successful failure? /s
If Crew Dragon needs to be launched to bring back the Starliner's passengers, that should be the final nail in Starliner's coffin.
I'm seriously shocked that NASA allowed themselves to be bullied by Boeing to allow this thing to have been launched at all.
> Maybe this is Boeing's way of slowing down Dragon capsule dockings?
I'm gonna go with Hanlon's razor here. The Starliner team seems to have enough trouble just getting a single Starliner to the ISS without issues, I can't imagine they're capable of devising a malicious plan to interfere with a competitor.
As far as I understand it, the point isn't just to pressurize the propellant to get it out of the tank and into the engine, but to maintain pressure so that the propellant remains liquid.
If the pressure in the tank drops, the propellant would turn into gas which would effectively be lost and potentially dangerous (by allowing flames to go the wrong way).
As your link points out, helium is nice because it is inert and remains a gas even at liquid hydrogen temperatures.
> [Helium helps to] maintain pressure so that the propellant remains liquid.
IANA rocket scientist, but this doesn't ring true to me. Vaporization of LH2 is related to the partial pressure of Hydrogen, not the absolute pressure of the gaseous phase. You're going to lose ≈PV/RT of hydrogen molecules to the gas phase regardless (P being the vapor pressure of Hydrogen at the tank's temperature and V the volume of the tank).
You still need the absolute pressure for structural stability. He has ≈twice the molar mass of H2, so H2 is better for the dry mass in the rocket equation anyway: what is left in the tank isn't wasted, but used for rigidity.
You just need Helium because it won't have phase transitions: it's always a gas so it is easier to regulate pressure.
> The command module attitude control system consisted of twelve 93-pound-force (410 N) attitude control thrusters, ten of which were located in the aft compartment, plus two in the forward compartment. These were supplied by four tanks storing 270 pounds (120 kg) of monomethylhydrazine fuel and nitrogen tetroxide oxidizer, and pressurized by 1.1 pounds (0.50 kg) of helium stored at 4,150 pounds per square inch (28.6 MPa) in two tanks.
I believe it's fed into fuel tanks as they are depleted in order to maintain pressure in the tanks. Being inert it doesn't have any impact on subsequent combustion or fuel reaction.
Weird they just didn't plan for this incredible opportunity from the start but sounds like they are just taking extra time as an opportunity not because they need to evaluate any safety issues (at least per Boeing).
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