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Falcon Heavy Launch [video]

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Re: Falcon Heavy Launch [video]

#291

Post by krisoft »

TremendousJudge wrote: post #157
krisoft wrote: post #134

Earlier quoted context omitted.

I will bite. Why won't the laws of physics and chemistry allow it?

To be more precise: the laws of physics and chemistry will never allow to pull CO2 from the atmosphere in an energy efficient way The consequence is that, unless all your electricity generation and raw resource extraction needed for the process has basically zero emissions, it's probably better to just use regular fuel. Burning fossil fuels to create fuel that you then burn has more CO2 emissions than just burning fo…

> To be more precise: the laws of physics and chemistry will never allow to pull CO2 from the atmosphere in an energy efficient way

I see. Now that is a big difference. I don’t know enough to tell if you are right.

> it's probably better to just use regular fuel

Maybe. There is one reason why spacex might still do it even if it is less energy efficient.

Their mars plan depends on in-situ resource extraction. If they can’t generate fuel on mars they can’t send their rockets back.

This will be a very hard technological challenge. If they can find a path to derisk their co2->methan plants here on earth it would be worth doing it even if it costs them money. They have to master the tech anyway.

Now clearly doing the conversion here on earth is not the same deal as doing it on mars. The atmosphere is quite different as a start. I don’t know enough to tell how much this matters. Maybe they can just tweek some process parameters and make a machine which works here on earth and on mars “sameish” enough that it helps with learning. Maybe they can process the exhaust of some industrial process into a kind of “martian atmosphere” analogue close enough that they can learn from that.

They will want to test their ISRU equipment before heading to mars. And they want to it eventually in large enough scale that the output can power their rockets back. It stands to reason that even their tests must be at a certain point on a huge scale. So why not fill the methane they get from the testing into their rockets at that point here on Earth too?

Re: Falcon Heavy Launch [video]

#292

Post by natch »

anon291 wrote: post #78
dools wrote: post #30

Quoted post unavailable.

It's pretty amazing and makes me feel proud that in our country, America, there are several private individuals and companies who are capable of launching rockets into space (it's not just Mr Musk), despite the fact that in other countries, this is something that requires massive government support. America's private-sector is heads and shoulders more advanced than many foreign governments. That's amazing to see.

In the US there is government support in the sense that companies can compete for and win government contracts, fwiw. But I get what you’re saying. We are lucky to have the right conditions overall for entrepreneurial efforts to have a chance at succeeding. And it would be wise to continue fostering this.

Re: Falcon Heavy Launch [video]

#293

Post by pencilguin »

mr_sturd wrote: post #245
gpm wrote: post #219

Earlier quoted context omitted.

They paid more, something like $150M I think "no one pays that" has more to do with "every mission is actually a negotiated contract" than "the price is inflated". https://www.nasaspaceflight.com/2022/10/falcon-heavy-ussf-44...

Fair enough, I'd naïvely thought of it as a ceiling.

Try that next time you stay in a hotel, or fly. Usually you pay more, often a lot more. But sometimes less.

Probably most SpaceX customers pay more. (Oh, you wanted it not tumbling?)

Re: Falcon Heavy Launch [video]

#295

Post by m_mueller »

Cerium wrote: post #208
TOMDM wrote: post #162

Earlier quoted context omitted.

$1,000,000 per lb for R&D is steep, but at this stage in the game makes sense. I wonder what the unit price for a break-even 1lb saving would be. Is it worth spending $20,000 to shave off a pound with expensive materials?

About $2600 per pound. Based on this forum thread [1] the marginal cost per pound to fuel efficienciy is about "0.0155 gallons per pound per 1,000 statute miles". Over a 737's life it may fly about 50 million miles [2]. Combining facts one and two results in a fuel consumption per marginal pound of 775 gallons. Current jet fuel prices are about $3.40 per gal [3]. [1] https://www.flyertalk.com/forum/travelbuzz/712294-…

If that’s the case, why is e.g. 10% of a 787 still using steel rather than titanium, which can be had at 11$ per kg?

Re: Falcon Heavy Launch [video]

#296

Post by bombcar »

boogies wrote: post #279
bombcar wrote: post #221

Earlier quoted context omitted.

You'd love Gasworks Park in Seattle: https://www.seattle.gov/parks/find/parks/gas-works-park

> TLS error [ignore] > About > Gas Works Park has a play area with a large play barn, and big hill popular for flying kites. Special park features include a sundial, and a beautiful view of Seattle. Access to Lake Union is restricted at Gas Works Park, as the lake sediment contains hazardous substances. Appear that that description omits the lede! But the park does seem singularly interesting per the Wiki article: ht…

Yeah, the picture captures some of it, but you really have to see it (preferably with kids) as there's just giant old industrial equipment painted and ready to climb on. Some of the valves even turn!

Re: Falcon Heavy Launch [video]

#297

Post by fallingknife »

tyho wrote: post #194
fallingknife wrote: post #131

Earlier quoted context omitted.

Good. Call China what it is.

A country with a impressive history of not declaring war on another state and who has drawn the ire of USA simply because they see it as credible economic competition?

You mean like when they totally didn't annex Tibet? Or when they didn't attack Vietnam in 1979?

Re: Falcon Heavy Launch [video]

#298

Post by elil17 »

TOMDM wrote: post #162
elil17 wrote: post #130

Earlier quoted context omitted.

The planes are so expensive because they're specialized planes meant to be in the air nearly 24 hours a day - this justifies spending a huge amount of money on improving their fuel efficiency. A friend who works in large commercial aircraft once told me that the break-even point for money spent redesigning planes to be lighter was $1,000,000 in R&D spending per pound of weight saved. Older models which are typically…

$1,000,000 per lb for R&D is steep, but at this stage in the game makes sense. I wonder what the unit price for a break-even 1lb saving would be. Is it worth spending $20,000 to shave off a pound with expensive materials?

Well that's the break even price. They want to have most 1lb improvements cost them less than a million dollars.

Re: Falcon Heavy Launch [video]

#299

Post by elil17 »

m_mueller wrote: post #295
Cerium wrote: post #208

Earlier quoted context omitted.

About $2600 per pound. Based on this forum thread [1] the marginal cost per pound to fuel efficienciy is about "0.0155 gallons per pound per 1,000 statute miles". Over a 737's life it may fly about 50 million miles [2]. Combining facts one and two results in a fuel consumption per marginal pound of 775 gallons. Current jet fuel prices are about $3.40 per gal [3]. [1] https://www.flyertalk.com/forum/travelbuzz/712294-…

If that’s the case, why is e.g. 10% of a 787 still using steel rather than titanium, which can be had at 11$ per kg?

The challenge is with design, certification, and manufacturing (forming and joining), not with affording the material. Plus, high strength steels can bear more stress than titanium, although they weigh more. This may be needed for certain space-constrained components.

Re: Falcon Heavy Launch [video]

#300

Post by elil17 »

snovv_crash wrote: post #253
TOMDM wrote: post #162

Earlier quoted context omitted.

$1,000,000 per lb for R&D is steep, but at this stage in the game makes sense. I wonder what the unit price for a break-even 1lb saving would be. Is it worth spending $20,000 to shave off a pound with expensive materials?

That doesn't make sense. So if I buy a top spec model and make it 400lbs lighter I can double the price?

A 1 lb saving saves $2,600 in fuel costs over the life of the craft.

However, an airline's break even point is a portion of that (perhaps $1,000) because the fuel costs are spread out over the life of the craft and there is an opportunity cost to spending money on the more efficient plane.

Of that $1,000, the aircraft maker will only capture a portion of the value - the airline expects to do better than break even. The airplane manufacturer may be able to charge $500 more for the aircraft.

They might hope to make 2,000 aircraft for something big like a 787 (although that number varies a lot depending on the model). That's 2,000 units times $500 = $1 million.

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