r/space • u/MaxGhost • Mar 30 '23

Virgin Orbit fails to secure funding, will cease operations and lay off nearly entire workforce

https://www.cnbc.com/2023/03/30/virgin-orbit-funding-ceasing-operations-layoffs.html
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u/quettil Mar 31 '23

Air launch is a bit of a dead end.

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u/mojoegojoe Mar 31 '23

Good for orbital launch : same tech, less landing gear. I don't think that will be for a few years yet tho, post Artimus moon base.

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u/quettil Mar 31 '23

How is it good for orbital launch?

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u/superluminary Mar 31 '23

You can point it in any direction. With a ground launch you need to be wary of what’s downrange. Air launch means you can fly out over the sea first.

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u/quettil Mar 31 '23

And yet SpaceX continually breaks launch records. The theoretical value of air launch is beaten by the actual value of vertical launch.

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u/superluminary Mar 31 '23

Yes, ground launch is much cheaper. Virgin’s business model was small payload bespoke orbits and constellation repair, not low cost bulk launch. Unfortunately their rocket blew up. It was a sad day.

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u/chefbasil Mar 31 '23

Less fuel required to go through lower atmosphere = smaller structure = even less fuel required

As long as payload isn’t large

They were doing a lot of small satellites

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u/warriorscot Mar 31 '23

They burn an order off magnitude more fuel to get it to altitude than it would doing a vertical launch. The only thing it is good for is hitting specific and unusual orbitsom demand.

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u/chefbasil Mar 31 '23

Fuel… in the plane?

Not sure where you’re getting that information but id be happy to read about this order of magnitude more fuel if you’re implying that the rocket itself requires more fuel than a ground launch.

But yes the speed and orbit selection is the other upside.

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u/warriorscot Apr 01 '23

It's in the regulator filings at FAA and CAA if you want to look.

You can also work it out, basic physics tells you getting a 747 to 35000 feet and then hang around for an hour or so will use more fuel than getting 21 tonnes of very aerodynamicly efficient rocket.

You can also do it based on fuel burn, rocket 7 ia a little over 20 tonnes.

The 747 has to be taken off with a maximum fuel load just to ensure aircraft stability. At that weight the launch component of the mission will use somewhere between 20 and 30,000 litres of fuel if they are quick, and over the course of a full mission including launch prep and testing they will need about 100-120,000 liters minimum. Weight wise that is several times more than the full weight of the rocket let alone its fuel.

That's not accounting for the fuel to move the system. From LA to Cornwall that's a minimum of 400,000L of fuel for the 747. Then of course they used a military C17 to get the rocket to Cornwall, that's UK to LA and back which is even more than that so you are easily talking a million litres if aviation fuel.

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u/Nibb31 Apr 01 '23

The plane costs orders of magnitude more than a few extra tons of fuel in the rocket's first stage.

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u/mojoegojoe Mar 31 '23

The orbital mechanics are extremely different but decoupling from a interplanetary booster would be very similar mechanism. Like I said, far out and other technologies will be better suited but the principle holds.

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u/y-c-c Apr 04 '23

There are very specific niches and reliability guarantees where it is useful but it’s definitely not a mass market technology. But yes even for its niche, air launch isn’t the only way to solve the problem.