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Comment by meritt | Hacker News Reader

You know we've had supersonic passenger jets since 1969, right? It just wasn't cost-effective. https://en.wikipedia.org/wiki/Concorde

SpaceX has brought reusability to space travel. That's slightly more impressive than a fast airplane.

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> SpaceX has brought reusability to space travel

Err... is trying to bring?

They brought the first stage back, and already have launch customers interested in flying on the used stage to get a cheaper price. I agree that the last step, of course, is a successful flight on a previously used booster.

That's not even the last step, really - it would prove that they could do it but that's it. What they really need to change the game is to get down full and rapid reusability. SpaceX estimates are that they could do launches at $7M if they could land a rocket, refuel it and launch it again. I'd say the "last step" is rapid, automatic and full rocket reuse, like an airplane. This is probably still 4-5 years away (at minimum) I'd guess.

I feel like that's a bit of an exaggeration. The cost savings isn't in Southwest-style 20 minute turn around. It's that you're not throwing a booster worth tens of millions of dollars away at each launch.

Well, it's both. If SpaceX wants the demand side of the market to expand sufficiently for its business model, it will have to launch that frequently. Also, the faster you can launch, the fewer rockets you have to build for your fleet.

Note that according to spacex fuel is only 0.3% of the cost, but materials are also only 2% of the cost. (http://www.space.com/21386-spacex-reusable-rockets-cost.html)

A rocket is not worth 10s of millions in raw materials, so it is the process of creating it that makes it worth tens of millions. So the 10s of millions of dollar question is: how much cheaper is the process of re-using a rocket vs the process of building a new one? It seems impossible to ever fully recoup the other 97.7%, but how much can they?

Yes and one went boom in 2000 killing everyone on board. https://en.m.wikipedia.org/wiki/Air_France_Flight_4590

The only reason this idea is even being entertained right now is because oil prices are so low. As soon as the oil producers are finished crushing this round of alternative energy companies oil prices will go back up and Boom won't sound so good.

Other airplanes have crashed too. I think it was deemed a fairly safe aircraft, they had some trouble with tyres, but that shouldn't be impossible to resolve.

It was retired from service largely because the accident was attributed to a critical design flaw.

Sure, that was the only ever Concorde crash, but then they really didn't fly very much compared with conventional aircraft. There are individual commercial aircraft that logged around as many flight cycles as the entire Concorde programme without incident.

I know they have recurring problems with tyres (and I'm sure they had other design flaws too).

But afaik the main culprit in the crash was a piece of titanium that fell off from another airplane and was left on the runway. This metal-piece cut into the tyre and caused an explosion.

Some investors don't believe that an oil price rebound is inevitable in the medium term. Boom is a great opportunity for such an investor, because it has different characteristics than does selling options.

I can't imagine a serious investor that doesn't consider oil price volatility when deciding whether or not to invest in an airplane company. You seem to be assuming that all of the investors are abjectly incompetent.

I think you're right that it would be considered, but from inside the VC world, I can also say it would be very very strange (to the point of almost unthinkable) for a fund to make a meaningful hedge against a particular portfolio company's commodities exposure. It's just not done, at least if you're running other people's money.

You can think of lots of reasons why, but it mainly boils down to this: VCs are hired to make bets within an asset class (startups) and not outside that asset class. Institutional investors (upstream of VCs) have other managers to do commodities etc.

Also, at least in theory, the market price of oil takes all info into account. If the VCs could really predict the price of oil in 3-5 years, they should probably be trading that alpha instead of investing in VC.

I'm not talking about hedging (like buying call options). I'm saying that oil price would be expected to be a potentially large part of the risk profile of the business, so it doesn't cut muster to just assume that the price of oil won't go up and cut a check. A competent investor will analyze the impact of common risks for the type of business in question, and make a determination as to whether the investment makes sense in light of the risks.

That doesn't mean that the investment isn't expected to be hurt (or wiped out completely) should the price of oil rise, it just means that a competent investor would have looked at that possibility and decided that the investment was still worthwhile.

The comment I was responding to IMO assumed flippancy on the part of investors and implied that they would be surprised by an increase in oil. That's absurd.

You can very easily buy options and futures oil and hedge away the risk for quite a while. Serious investors do this.

The shuttle was reusable, it had plenty of other issues. IMO, mostly centered around how bad government procurement is. ex: polar orbit

There's a really big difference between how 'reusable' the Shuttle was compared to what SpaceX is trying to achieve. SpaceX's goal is not just reusability, but "full and rapid" reusability, where the entire system is reusable with minimal refurbishment/inspection. The Space Shuttle took months of inspection, tens of thousands of people to work on it and countless millions of dollars to get ready for the next launch - and only a fraction of it was actually reusable.

SpaceX is still very far from their goal, but it's worth describing that "full and rapid" reusability was not how the Shuttle worked. A reusable SpaceX rocket would be able to launch, deliver payload to orbit, land, refuel itself and load the next payload all in less than 1 hour and with a cost of ~$300k. They are very far from that of course, but it's a fantastical goal.

Nope, SpaceX is not trying to reuse the second stage. The shuttle reused the second stage (the shuttle) and the booster rockets, just not the 'cheap' external fuel tank.

Remember the second / final stage get's to orbit so return needs a heat shield or an obscene amount of fuel. The shuttle demonstrated the issues with reusing heat shields very well.

PS: IMO, Space X is all about execution not technology. Landing a first stage rocket vs using taking a dip in the ocean is probably a good trade-off. But, most of there gains are about being lean and making incremental improvements.

They are not trying to reuse the second stage of the Falcon 9 rocket. They are planning for full reusability of their future rockets, however. That's what I'm talking about when I'm talking about their plans for full and rapid reusability. This is not something the Falcon 9 will achieve but is in their plans for reusability.

IMO, your overstating things. They mentioned back in 2012 plans for a reusable upper stage and even had a basic video. But, that second stage is a very hard problem and there not actively working on / testing it. So, if you want to include something that's little more than a power point deck then your a far more generous man than I.

ED: It's the classic doing X, trying to do X, or hope to someday do X.

The plan for the shuttle was 50 flights a year, with greatly reduced launch costs. It didn't work out that way. We'll see about SpaceX: they have one successful 1st stage recovery, and no re-launches yet. I hope they are successful, but they're a long way from proving that they can bring launch costs down all that much.

Some people would argue it was cost effective. It was just prohibited from competing by Boeing lobbying to get it banned from the most profitable routes

Concorde cost £1.134 billion to develop around 1965. That's like $10bn+ inflation adjusted.

The key innovation is that they are building an economic, supersonic airplane. That was what SpaceX brought to space travel, and what has never been built in supersonic air travel.

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