48

I’ve continued to do a bit of research on this, and what we’re seeing falling away are two of the lithium-ion battery packs that power the Rutherford engine turbopumps. The Rutherford engine is unique in that its small size allows it to utilise an electric pump-fed cycle. On the second stage in particular, there are three lithium-ion batteries, two of ...


26

A flywheel is so efficient because it is big and heavy, both of which you don't want to add to a spacecraft. As for spinning an existing component, the only parts of a rocket that really have any significant mass (would justify the additional bearings and generator) would be fuel tanks. Spinning a fuel tank with liquid fuel in it would be tricky though, ...


17

This claim of "efficiency" is factually accurate but nearly meaningless as a measure of a rocket's performance. It's similar to pointing out that a car has high-efficiency LED headlights. That's great but it doesn't necessarily mean the car will have better performance or economy. In a gas generator cycle, a small amount of fuel and oxidizer are burned to ...


12

In principle, this should be possible. The question is, is it practical? An example flywheel used in car racing (i.e. a high-performance, cost-no-object application) weighs 18 kg and stores 400 kJ = 400 kWs, is 111 Wh, or 6.1 Wh/kg. A Li-ion battery has a specific energy of 100–265 Wh/kg, 16-44 times higher. So the flywheel solution needs far more ...


11

This is ice breaking away from the vehicle due to vibration, acceleration and aerodynamic forces. The Electron uses cryogenic liquid oxygen and kerosene as its oxidiser and propellant. The low temperature (approx −185 °C) in the tanks causes water vapour from the atmosphere to condense and freeze onto the body of the rocket. This can can be seen on the ...


10

You're quite right that 150kg is unlikely to be the final maximum payload for Electron: SpaceX's Falcon 1 was almost immediately uprated with the addition of a Merlin-1C engine, and was nominally planned to be offered in an extended variant, Falcon 1e, that could take 1010kg to LEO. The most likely upgrade path probably consists uprating the Rutherford ...


9

The blue cylinders contain electric motors that are used to vector the engine assembly. This could be either a linear motor or a conventional motor driving e.g. a thread screw. The pumps and the thrust vector actuators on the engine have brushless DC motors powered by batteries. This means they can avoid hydraulics, simplifying the design. In this 2018 ...


7

Spaceflight Now uses the word 'deploy' in an unusual sense. We normally expect it to mean 'separate the payload from the rocket', but here they mean 'separate the combination of kickstage and payloads from the second stage'. So all the satellites end up in a circular orbit. From RocketLab's site: These new payloads join existing ‘It’s Business Time’ ...


5

A mostly un referenced list would include: Needing to design rocket structure to bear load horizontally pre launch as well as vertically under thrust. Classic rocket design supports the rocket against 1G at the engines using the same structural elements that must handle several Gs in flight anyway so ground based support are largely 'free' other than ...


4

The other answerers have failed to do their research correctly. NASA and China are both researching this. The idea is it helps increase the life of the battery on board since there are less charge cycles - but a battery is still used because by just using the flywheels for energy storage, the life of the flywheel bearings is reduced. Using both provides ...


4

Tim Dodd, the Everyday Astronaut, just uploaded an interview with Peter Beck from Rocket Lab where he asked exactly this question. His answer was that soot build up at the injector and breaks lose from time to time. So basically its just carbon that lights up due to the heat. Unofficial transcription based on listening and watching YouTube's inacurate closed-...


4

tl;dr: According to currently published numbers, No, not at present, but... The Wikipedia article section OneWeb satellite constellation; Design characteristics tells us: The satellites in the OneWeb constellation are approximately 150 kg in mass, a bit smaller than the 2015 design estimate of 175–200 kg (386–441 lb). The 648 operational satellites are ...


4

The design constraints for air launch are more about the first stage being able to light while horizontal (no fuel sloshing away from intakes), and the structural additions to support being hung fully laden sideways rather than vertically in the same direction as thrust loads. There also needs to be the flight controls to achieve the pitch up, which may ...


4

In this image of a Falcon 9 takeoff (CRS-14), you can see some transparency in the exhaust of the (much larger) Merlin 1D: I can make out the rear half of the engine bells through the exhaust (this is clearer in the much larger original of the photo, so click to enlarge). Now comparing to the Rocketlab photo, the structure of the exhaust is different, ...


3

According to Virgin Orbit's Service Guide: Up to 300 kg / 661 lbm to 500 km / 270 nmi Sun-Synchronous Orbit (SSO) Up to 500 kg / 1100 lbm to 230 km / 124 nmi circular 0 degree inclination Low Earth Orbit (LEO) Virgin Orbit claims variously to launch between 0°- 120° and 0°- 180° in different literature. However, since air-launch provides a very ...


3

They're back to their old plan of launching Pegasus XL. In a statement to SpaceNews, a company spokesman said that the company was ending work on its own family of launch vehicles and would instead use its aircraft for launching small Pegasus XL rockets from Northrop Grumman. News of the change in plans was first reported by GeekWire. “Stratolaunch is ...


3

Partial answer (for Centaur and Saturn 1-B) The H2 line emerges from the boost pump, which is mounted at one side of the base of the H2 tank. The line then wraps around the O2 tank and splits near its base to reach both engines. The O2 line emerges from its boost pump which is located in the center base of the O2 tank. The line splits almost immediately ...


1

Recently in an interview with Micheal Sheetz, Peter Beck mentioned that the Electron “We actually showed that we could not only get to the moon, but we can do near-interplanetary stuff. We can go to Venus, we can go to Mars,” Beck said. Then in an interview with Everyday Astronaut, he said; "we can even get 20 odd kilograms to Venus" Note: The ...


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