Virgin Galactic's SpaceShipTwo completes 2nd powered flight | Hacker News Reader

Virgin Galactic's SpaceShipTwo completes 2nd powered flight

cnn.com

68 pointstimjahn25 comments

Good for them, but man it's been a long time. SS1 won the X-Prize almost exactly 9 years ago, and apparently took about 3 years to get there. I know a revenue version is going to have more details to attend to, but that's still a long time for approximately the same system.

My understanding from the "industry" is that most of the delay was in scaling the hybrid engine up. Which I can imagine, as it's the largest operational hybrid ever made--though a smallish motor as far as conventional liquid or solid rocketry goes.

I wonder if they regret pioneering in this particular area. If it works eventually (and looks like they finally got it going) it may work out okay, but they'd probably have been flying years ago with a liquid system. As is they may just barely beat XCOR (which has next to no money in comparison) into revenue flight.

Personally I don't doubt that the hybrid approach was a poor idea (if for no other reason than casting and reloading giant rubber grains seems cumbersome in comparison to re-filling with kerosene), but we'll soon have a hybrid rocketplane (SS2) and a liquid rocketplane (Lynx) flying side-by-side, so I guess we'll see. Though Virgin's money and press may tilt the playing field.

I think it comes down to safety. Supposedly the hybrid is a safer rocket motor than a conventional liquid engine. I understand their concern. They already have 600 tickets sold at $250k a piece and if on launch number 40 the rocket goes BOOM, which liquid rockets are prone to do, it could be a disaster. I think eventually it's a given that one of the rocket motors will explode. Hopefully when the hybrid one goes, say from a air pocket in the solid fuel, it won't be a fatal disaster.

That all being said - space is dangerous. I hope people are prepared for all that entails.

Agreed, They might as well close the company when a disaster happens. I wouldn't risk my life for 3 minutes of weightlessness. A week or two in space is another story.

Yeah I don't like the idea of going to space for a quick trip very much. Rockets are incredibly powerful, and hence dangerous, machines. Never mind all the inherent dangers of the environment. It's just not enough pay off for me.

One could always take a lift on the vomit comet if they want to feel weightless: http://en.wikipedia.org/wiki/Reduced_gravity_aircraft

A trip to the ISS though? Holy cow I'd risk my life to go there. 300km orbit for a few weeks? It's just too much to pass up.

Of course you are right it would be a complete disaster. However that might not be the end of it all.

HN's SimonW gave a talk at Electromagnetic Wave 2013 about the fun and frolics of Zepplins.

Apparently plenty of them crashed and burned, but people kept travelling on them. Early aeroplanes would crash too.

http://lanyrd.com/2013/emw/scgptt/

There's very little evidence of their hybrid rocket motor being safer than liquid fueled engines. An accident at the Scaled Composites plant killed 3 people and severely injured several others during a test of the rocket system, for example.

Also, liquid rockets are not particularly prone to "go boom", the most likely failure scenario is a loss of control, but that can happen to any rocket.

Scaled Composites had an accident back in 2007 with SpaceShipTwo that killed three people while they were testing their N2O tanks on the ground. I think that may have set them back a few years.

I am looking forward to this being available. I consider it one of the bell weathers of the private space flight 'business.' A healthy source of revenue for private access to space will change the market dynamics on what gets built, a small niche revenue will not. Either way, we get a data point.

The thing that would concern me is that once the novelty wears off, and there's no place in particular to "go" in space, a healthy revenue source might be difficult.

Jerry Pournelle once suggested that while there is no place to "go" in space, that "doing things" in space was always entertaining in its own right. And by "doing things" he strongly hinted that he felt that "doing it" would be the strongest driver.

I expect he is correct, and don't doubt for a minute that if the Bigelow Space guys figure out how to deploy a hotel in space, an entrepreneur will deploy a bordello.

ha! I agree.

I'm actually thinking most of the promise in getting places to go built will be a by-product of astroid mining. But we'll see.

Nausea and not having any idea how to move around effectively in space probably mean a space love hotel wouldn't be a good idea, despite Pournelle's hopes.

Actually that is one of the novelties. If you've got a lot of experience you know all the 'moves' but you lose some of the 'fun' of figuring things out.

I've seen an analysis which said that the revenue source isn't going to space and back, but going really fast between 2 points on earth. The analysis basically said that with mail delivery you pay up to 5 times as much for the fastest delivery tier as you do fo the second fastest and that there are about 10% as many deliveries at the fastest tier as at the second fastest. So if you could use space ship 2 for an even faster tier and could get 10% of the current fastest market for 5x the price, then there should be enough mail to pay for up to 1 flight per day across the country.

> 1 flight per day across the country

Don't we already have same-day delivery? So the next tier would have to be quicker delivery than that, which would necessitate more than one flight a day. Is it still economically viable in that case?

Does this same economy math apply to passenger transport? Or could one flight per day of mail to the other side of the world be worth it?

Or, this means that the same-day delivery radius is much greater ... as well as the subsequent tiers below that, regarding express shipping.

There's something there in your point. But I think the kind of launch and landing infrastructure requires these kinds of things be pretty far from important population centers...meaning your short rocketship trip would be bookended by interminable ground transport.

"designed to carry up to six passengers on what will be suborbital flights at first."

Unless I am mistaken, I don't think there are plans on ever getting SpaceShipTwo orbital; Mach 1.43 is an order of magnitude away from what you need for LEO. I am guessing they mean that in the future Virgin Galactic will orbit something else.

Yes the delta-v needed to get to an altitude of 100km is about half of what one needs for LEO as far as I know.

So it's probably about ~3-4km/s for SpaceShip One. I'd have to calculate it from 50k feet using some specs to find out for sure.

http://en.wikipedia.org/wiki/Delta-v_budget

SpaceShipThree was* planned for orbit. http://en.wikipedia.org/wiki/SpaceShipThree

Edit: * was planned for orbit.

from your link;

"As of 2008, the company has scaled back those plans and articulated a design that would be a point-to-point vehicle traveling outside the atmosphere."

Current space-hops just can't be anything more than a tourist attraction. Looking at the design it seems the ship is unable to do atmospheric entry from orbit and is a dead end as far as research is concerned.

There's plenty of research to be done in a suborbital flight regime, both standard sounding rocket stuff and new types that can benefit from either more room onboard or even from a human operator, or simply enabled by lower costs and greater availability and/or frequency.

Lots of it may be testing things out destined for eventual orbital use. In a suborbital flight you can get many minutes of freefall, which beats the seconds available on parabolic flights (which are used for lots of the same experiments now.)

NASA has a whole program for collecting experiments for suborbital flights, and Masten in particular is focused on research uses.

I shouldn't be surprised if they fly a lot of potential orbital-flight candidates on suborbital just to get them used to freefall.

Suborbital may not be a good as orbital, but it's much much cheaper, and cheapness has a quality all its own.

At a worldwide market size of $1.4 trillion (http://www.ibisworld.com/industry/global/global-tourism.html), "just a tourist attraction" is not a bad place to be at all.

If the Skylon manages to get built to spec and gets ~30 people into orbit for $10 million per launch, then an eighth of the worldwide tourist budget could launch a million people a year. Though, presumably if you were launching that many people, the cost would actually be a fair bit less.

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