Nothing has been "overlooked", the fairing was designed for a launch vehicle of a certain class years ago before the capability of the launch vehicle significantly increased. That Ariane 5 has a "payload advantage" (more like 1.5x, actually) is apparently not that crucial since Ariane 6 allows to scale it down. Right now, Ariane 5 has operational problems with mating matching payloads.
Since many real-world payloads are volume-limited rather than mass-limited, the 20 tonne capability of Falcon 9 is being seen as less relevant. For example, the 20-tonne ATV spacecraft would have never fit into Falcon 9's fairing. It was more than ten meters long at a 4.5 meter diameter but the F9 fairing stops being 4.5 meters wide internally before 8 meters of length. It fit nicely within the 40% larger Ariane 5 fairing.
The fairing is dropped pretty close to the time that stage 1 ends its burn, and most of the delta-V is in stage 1
It's around 2 km/s for Falcon 9 with landing the first stage, with a total delta-v of around 10 km/s for GTO missions. So I'd say that most delta v is in the second stage, unless you were trying to say something else than I thought you were trying to say. The F9 throws away the fairing shortly after igniting the stage 2 engine (after expending around 15 tonnes of propellant in the latest flight), at the point when the total mass of the remaining stack is still around ~100 tonnes, so I'd be very surprised if the effect were any higher than, say, 0.3 kg of payload for 1 kg of fairing mass delta. And that can be overshooting a lot still, I'd have to make a more accurate calculation of my own, but the calculator at http://www.silverbirdastronautics.com/LVperform.html gives me quickly a figure of around 0.1 kg of payload mass lost per 1 kg of fairing mass increased (for a GTO profile), which sounds intuitively about right to me.
If it's a pound heavier, that's a pound you can't have for payload.
Not really, if they're discarded nowhere near orbital velocity. (However, if it's too heavy, it's impractical to land by means of parachute, etc. etc.) There's some loss but nowhere near 1:1.
There's no vacuum, only significantly decreased pressure. It's a little bit like the difference between metallurgic grade silicon and IC-grade silicon. The difference in silicon contents is rather small but still one of the two is significantly cheaper than the other. The hyperloop concept reminds me more of the high altitude test chambers for rocket engines like NASA's B-2 facility which maintains decreased pressure continuously even with a rocket engine inside the vacuum chamber spitting a hundred kilograms of exhaust gases into it every second.
Why would it have to be less efficient when it minimizes aerodynamic drag by design? Perhaps some other things compensate for it, but overall I don't see an inherent reason for it to be less efficient.
Or maybe you totally misunderstood *his* argument. Being able to conveniently burn up in the atmosphere has never been a major requirement for any space elevator concept I've ever heard of. All the analysis was focused on making the whole thing just stable in steady conditions in the first place.
Why would you store 48 megapixels in photos? The resolution is perfectly fine for resampling and quality digital zooming. Just like in CGI sampling filters, there's no need to store all subpixel samples.
Are you seriously classifying C++ with Javascript????
When it comes to the "design process", JavaScript really looks like the high-level equivalent to C++ - start with something and try to make something completely different out of what you already have.
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Nothing has been "overlooked", the fairing was designed for a launch vehicle of a certain class years ago before the capability of the launch vehicle significantly increased. That Ariane 5 has a "payload advantage" (more like 1.5x, actually) is apparently not that crucial since Ariane 6 allows to scale it down. Right now, Ariane 5 has operational problems with mating matching payloads.
But Bruce, Ariane has lifted a number of 20 ton payloads to LEO. Spacex cliams to be cheaper, but nobody in the 20 ton class gives a shit about Falcon9?
Since many real-world payloads are volume-limited rather than mass-limited, the 20 tonne capability of Falcon 9 is being seen as less relevant. For example, the 20-tonne ATV spacecraft would have never fit into Falcon 9's fairing. It was more than ten meters long at a 4.5 meter diameter but the F9 fairing stops being 4.5 meters wide internally before 8 meters of length. It fit nicely within the 40% larger Ariane 5 fairing.
The fairing is dropped pretty close to the time that stage 1 ends its burn, and most of the delta-V is in stage 1
It's around 2 km/s for Falcon 9 with landing the first stage, with a total delta-v of around 10 km/s for GTO missions. So I'd say that most delta v is in the second stage, unless you were trying to say something else than I thought you were trying to say. The F9 throws away the fairing shortly after igniting the stage 2 engine (after expending around 15 tonnes of propellant in the latest flight), at the point when the total mass of the remaining stack is still around ~100 tonnes, so I'd be very surprised if the effect were any higher than, say, 0.3 kg of payload for 1 kg of fairing mass delta. And that can be overshooting a lot still, I'd have to make a more accurate calculation of my own, but the calculator at http://www.silverbirdastronautics.com/LVperform.html gives me quickly a figure of around 0.1 kg of payload mass lost per 1 kg of fairing mass increased (for a GTO profile), which sounds intuitively about right to me.
Maybe an oversupply will bring the prices down a bit from being gawdawfully high.
Good thing I wasn't drinking coffee while reading that, otherwise you'd owe me a new keyboard.
If it's a pound heavier, that's a pound you can't have for payload.
Not really, if they're discarded nowhere near orbital velocity. (However, if it's too heavy, it's impractical to land by means of parachute, etc. etc.) There's some loss but nowhere near 1:1.
Ariane 5 has definitely more than 7 tonnes to GTO capability (for a lot more money than either of the F9 flight options, though).
I think you're actually looking for Frankenburg.
What do you call this? [isocpp.org]
A group of people trying to save the dog with the bolted-on legs?
Are you also going to admit that you have no working knowledge of C++?
Of course I am; I'm proud to admit that I don't satisfy this definition of insanity.
I admit it, C++ didn't have a design process. Modula, Ada, Haskell, Scheme etc. did.
Careful with those aneurysms! ;)
And a commercial passenger jet can travel at double that speed. And doesn't require spending billions of dollars to build hundreds of miles of track.
...and it can't run off of electricity. That's a bit of a bummer.
See my comment above.
There's no vacuum, only significantly decreased pressure. It's a little bit like the difference between metallurgic grade silicon and IC-grade silicon. The difference in silicon contents is rather small but still one of the two is significantly cheaper than the other. The hyperloop concept reminds me more of the high altitude test chambers for rocket engines like NASA's B-2 facility which maintains decreased pressure continuously even with a rocket engine inside the vacuum chamber spitting a hundred kilograms of exhaust gases into it every second.
Why would it have to be less efficient when it minimizes aerodynamic drag by design? Perhaps some other things compensate for it, but overall I don't see an inherent reason for it to be less efficient.
You'd probably use an electromagnetic accelerator if you wanted to do that, but overall the idea doesn't make sense anyway.
They don't even fly them once before they're put to work.
Not yet.
Or maybe you totally misunderstood *his* argument. Being able to conveniently burn up in the atmosphere has never been a major requirement for any space elevator concept I've ever heard of. All the analysis was focused on making the whole thing just stable in steady conditions in the first place.
The space elevator itself is exceptionally light (or "impossibly light," in the words of anonymous coward above).
And impossible things are trivially safe of course. ;)
If a space elevator breaks, the parts that are high up (and thus have high energy) disintegrate in the atmosphere
No, they just get ripped off and become dangerous orbital projectiles.
the parts that are lower down (and thus don't have much energy) sift down like dandelion fluff.
Megatonnes of danelion fluff? OK then...
Of course; all three have been "designed" extremely carelessly as far as programming languages go.
Why would you store 48 megapixels in photos? The resolution is perfectly fine for resampling and quality digital zooming. Just like in CGI sampling filters, there's no need to store all subpixel samples.
Are you seriously classifying C++ with Javascript????
When it comes to the "design process", JavaScript really looks like the high-level equivalent to C++ - start with something and try to make something completely different out of what you already have.
Well, my intuition has never been very good.
"Don't worry, his bark is worse than his byte."
You need more than 20 grams of explosive to do some harm
If it's anti-personnel, 20 grams and an explosively formed projectile are probably more than enough.