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Comment by iamrecursion | Hacker News Reader

I have to appreciate the humour this shows. All in the name of progress, and it certainly made me laugh.

SpaceX has somehow managed to turn landing a booster from space into something almost mundane, but it bears remembering the failures that got them there.

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You try and fail. And try and fail. And try and fail. And then one day you have learned enough to try and succeed.

Learning how to NOT land it is learning how to land it.

“I have not failed 10,000 times. I have not failed once. I have succeeded in proving that those 10,000 ways will not work. When I have eliminated the ways that will not work, I will find the way that will work.”

The trick with learning how to fly, is to throw yourself at the ground... and miss. - Douglas Adams

And if you're smart, rich and lucky, you learn enough before the funding runs out. :)

The failures were all very low cost since the rockets actually completed their mission. Once reusability becomes common and lowers the price of launches, failures like those will actually be very expensive for someone else.

Relatively low cost, yes. But all those recovery efforts, offshore barges, added hardware and software cost actual money that was away from their gross margin from the rocket launches.

It was a good move regardless but don't underestimate the amount of time and money spent.

Still relatively small beans compared to the cost of the rocket. Remember, they started out simple. They did controlled re-entry burns and let the rocket fall - cost: extra fuel and 10 minutes more of data collection. Then the did a descent down to sea level and a hover before falling into the sea - cost: extra fuel, grid fins (grid fins yet?), more data collection. By the time they went for a barge landing (sorry, drone ship) they had reasonable confidence in having some success - and they hit it. By that point the long term benefits should have been clear, so further development was investment in their future.

All of this should have been done a long time ago by the established players in the industry. It sounded crazy to them, but really the cost of experimenting with re-entry should not have been much and AFAIK they never even tried.

One big obstacle to established players was the fact that a lot of existing booster stages had been optimized in such a way that they simply could not survive atmospheric reentry, lateral stress, and could not land. Both major operational US rockets, Delta IV and Atlas V, have exterior insulation (which would burn away upon reentry), relatively thin walls (meaning they're not very strong against aerodynamic buffeting or fin torque), and single engines (meaning that it's very hard to throttle down to land). Adapting these rockets for reusability testing would have meant basically redesigning them from the ground up.

Probably more importantly, the idea of landing a rocket was basically impossible until computer control got good enough to handle the descent and landing.

For sure - but it's been good enough for a while. Consider the McDonnell Douglas DC-X in 1993: https://en.wikipedia.org/wiki/McDonnell_Douglas_DC-X

DC-XA set a height record of 10,000 feet, and pretty much goes straight up and down. So it proved out most of what Blue Origin's suborbital rocket does, and the last part of what SpaceX's first stage does, but not the re-entry burn and flying a cylinder stuff.

Soviet space shuttle Buran landed automatically from space in 1988 using Soviet-made hardware and software. So I very much doubt that using recent computer chips were essential to land the rocket.

> Adapting these rockets for reusability testing would have meant basically redesigning them from the ground up.

And now they're going to have to do that anyway if they want to compete with SpaceX, so what the GP said is true, it's something established players should have done a long time ago, and they're going to be noncompetitive for a period of time as a result.

Correct - they just went down the wrong optimization road, so the incremental development program for Falcon 9 landing is nothing they could have replicated.

Yes, sure it was an impressive R&D program that piggy backed on their production runs.

But it was still an expensive program with Grasshopper test vehicles, lots of failed tests and a reduced capacity on the boosters. "Just a little extra fuel" is a great oversimplification, there's much more than that in doing an atmospheric re-entry.

But a marvelous program it has been and I look forward to seeing their future progress.

The real cost of the "extra fuel" was really in making the base rocket big enough to address the majority of the rocket without add-on boosters. Then you always have leftover fuel for more moderately sized satellites. And in terms of design simplicity that might have been worth while before considering reuse.

I recall that they spent about $1 billion in landing-related R&D before they got it to work. Definitely a lot. (Although, for comparison, a single Shuttle cost about $2 billion to build, not counting any R&D costs.)

But if that $1 billion came from their margins rather than from investment, it means they wouldn't run out of funding unless they ran out of business, which is pretty cool.

I believe that the $1 billion figure is for the entire development cost of the Falcon 9 vehicle (stages 1 and 2.)

I wonder if that'll get added to the contracts as a possible cost to the customer.

"If Rocket is destroyed while operating for any reason, Customer will be required to pay the pro-rated portion of anticipated Rocket lifetime replacement cost, or insurance deductible, whichever is higher."

Like how UPS charges customers who have packages in the truck when they're involved in accidents?

I think the rental car model makes more sense. If your payload breaks the rocket, you're liable for it. I think this is Already the case with much rocket insurance.

I haven't heard of that. But I have seen UPS charge customers when their package gets run over by their trucks. "You should have packed it more securely"

Except for the Grasshopper fail, that must have hurt. But yes, their overall approach was genius.

As there is a definite Monty Python feeling to the video, I'd suggest this is appropriate: https://youtu.be/aNaXdLWt17A?t=20s

Did the Month Python music and quotes gave it away?

Congratulations on... noticing the same thing I did?

the road to wisdom - well, it's plain and simple to express: To err and err and err again but less and less and less

It's incredibly reassuring that ACTUAL rocket scientists have the same problems as people learning how to play Kerbal Space Program.

The part that made me laugh the most, however, was that Scott Manley had the top comment (when I looked, anyway).

For those who don't spend their off hours accidentally blowing up green videogame astronauts, or stranding them on distant planets, Scott Manley has the single most extensive tutorial series for Kerbal Space Program.

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