Nibb31

Twin Boeing = Stratolaunch. Stratolaunch is a dead end, for many reasons. The main one being that nobody wants to build a rocket for it.

It's always possible. The problem is how much are you ready to spend on isolating the root cause ? After Columbia, NASA spent millions of dollars on studies and tests. They tore down the other shuttles and did destructive testing on various components. They interviewed hundreds of people. They analysed thousands of pages of documents and procedures. The even built a special cannon to shoot supersonic blocks of frozen foam at RCC panels. If they had an unlimited budget and unlimited time, SpaceX could cycle test other cores through the same procedures to pinpoint the cause. They could verify their hypothesis by pushing hardware to its limits during destructive testing. But SpaceX is a private corporation that doesn't operate in the same economical or legal environment as NASA. They are on a limited budget and they have economical pressure to resume flights ASAP.

That is just ignorant. It shows that you have no understanding of how science works. I agree that we should be spending more on Earth science. We should also be spending more on astrophysics, social studies, economics, biology, and health research too. Scientific knowledge is the key to progress, even if you prefer some fields rather than others. The argument that NASA should be doing less science, or that we should be spending less in certain fields that you don't happen to like, is not going to help anyone. That is your opinion. Unfortunately, that is not what most taxpayers want. If you were to un a poll on what people care about, space exploration won't even register. It's a miracle that NASA gets the budget it currently gets. I also think space exploration is cool, but not the point where we have to gut scientific research to do it. Boots on the Moon don't really accomplish much. Understanding how our world works accomplishes a lot and helps us secure a better future. Earth studies have been part of NASA's charter ever since the National Aeronautics and Space Act in 1958.

Since the dawn of maritime law, there's always been a tradition of assisting and rescue people from other countries when necessary, regardless of their nationality, including during wars. Even at the height of the Cold War (which has been over for nearly 30 years now BTW). Many countries, including the US, offered assistance to help the sailors of the Kursk or to help with Cherobyl. It's SOP. At any rate, the Antarctic, like space, has always been an area of peaceful international cooperation.

ESA actually does. So do many other research organizations around the world. Climate deniers can deny the causes, but it's undeniable that stuff is happening and that we need to better understand exactly what is and why. To stop measuring the problem won't make it go away. Proposing cutting science budgets, just because you disagree with the results, is obscurantist, and we have enough of that already. Yes, they do that too. Ever heard of SOHO ? And ESA Solar Orbiter is scheduled for launch in 2018.

Cutting corners is not usually the best way to improve reliability. SpaceX doesn't exactly have a great record for that sort of thing... What would you think of an airline that offers half price tickets due to the fact that they have designed their own safety and maintenance procedures ? I'm sure there is room for optimization, but folks in the industry have decades of experience with launching rockets and they are not dummies. Those procedures exist for reasons, and usually lessons that were learned the hard way. You are ultimately handling huge amounts of energy in extreme conditions, so it will never be as mundane as filling up a truck. Actually, many components on Formula 1 race cars are usually worn out after a race and trashed, including the engines. They have in common that they run in extreme conditions.

I don't know what the nationality of the plane has got to do with anything. We all wish well to Buzz.

Some would argue that NOAA's budget is just as important as NASA's, so if NASA no longer gets to do Earth observation, then the budget that was used by NASA for that purpose should be transferred to NOAA, otherwise, you reduce America's earth observation capability, which would be a reckless thing to do with everything that's going on.

Why would it be more? The manufacturing cost of the first stage hardware is only a fraction of the cost of a launch campaign. The biggest cost is the workforce, not the hardware, and reuse doesn't do much to reduce the workforce, except for some manufacturing positions.

You don't necessarily need a high acceleration. You just need to go from 0 to 24000km/h. It's just easier to do it as quick as possible, because the less time you spend fighting gravity and drag, the less energy you spend.

That would have involved complete disassembly, reassembly, integration, and testing. It is cheaper to skip the disassembly part and just start with a new one. Also, if you only have one unit of a specific component that you reuse on each flight, what do you do if you find a fault or if you need an upgrade? You need to order another one-off to replace it, and that is super expensive. It is usually more efficient to build a batch of them in order to have a supply line for spares and to iterate improvements. Apollo landed in the Pacific because it required a splashdown area several hundred kilometers wide, without risking to land on hard ground. I suppose they preferred the Pacific rather than the Atlantic because there was typically less traffic. Most of the Mercury and Gemini missions splashed down in the Atlantic, and so did Apollo 7. For Apollo, the splashdown location was determined by the timing of the TEI burn (Trans-Earth Injection = when the Apollo CSM leaves lunar orbit). Basically, they had to set up the mission so that the TEI burn coincided with an alignment which would bring the CM into the correct place (an area in the ocean) at the correct time (during daytime to facilitate search and recovery operations) This is a (very old) but great educational video that explains everything you need to know about reentry and landing: The original plans were to reuse Orion and to make it land in the desert on airbags. Nowadays, that requirement seems to have been dropped and Orion is designed for splashdown, which makes reuse much harder. At this stage, you'll be lucky if it flies more than once or twice anyway. Nope, they are gutted and scrapped. Some electronics might be reused, but there really isn't much to reuse inside a Soyuz descent module.

Reuse isn't always cost effective. If you have a party at your house with 50 guests once a year, it will be much more economical to buy disposable cups and paper plates and not spend two hours to do the dishes. For a restaurant that serves 50 people every night, it is more economical to use non-disposable plates and to pay someone to do the dishes. The Apollo CMs were high-tech for the time, but they were pretty much scrap when they came back. The heat shield and back shell were destroyed, umbilicals were cut up, some parts were damaged by pyro events, and the rest had been exposed to seawater. Refurbishing and testing would have been much more expensive than simply building a new command module from scratch, which is what you had to do for the rest of the Saturn V any way. The command modules were only a small part of the total cost of every Moon mission, so it really wasn't worth it.

Actually, one big issue with SSTO is that you want to minimize drag on the way up (so a Concorde-style profile works well), but you actually want to maximize drag to decelerate on the way down (which is why the Space Shuttle, BOR, or DreamChaser have a blunt profile). It's extremely difficult to find an aerodynamic configuration that works well for subsonic lift, hypersonic ascent, reentry, and landing at the same time.

The X-43 flew at Mach 9 at an altitude of 33 km, which is twice the service ceiling of Concorde. It reached temperatures around 1500°C. On re-entry, parts of the Space Shuttle could reach 2000°C. Concorde was nowhere near capable of hypersonic flight, orbital flight, or atmospheric reentry. Even if you strapped rocket engines, a TPS, and RCS onto it, it couldn't carry nearly enough propellant to reach orbital speed. It was designed as a passenger jet, not a spacecraft. If you stuck it on top of an SLS and flew it to space, it still wouldn't be a spacecraft, just like if you sank it to the bottom of the ocean, it wouldn't become a submarine. Pedantic mode: The Mach number specifically refers to the speed of sound, which depends on air density. By definition you can't fly at Mach 25 outside the atmosphere.

No. If there is lift, there is atmosphere and therefore drag. If there is bouyancy, there is atmosphere and therefore drag. Either way, they need propulsion that can provide 9000m/s of dV while countering both the hypersonic drag that applies to a balloon the size of Manhattan and the gravity that applies to a several thousand-ton tank of propellant and the massive structure and heatshield that prevents that balloon from collapsing under its own weight or burning up in the 2000°C hypersonic airflow.

The propulsion still needs to overcome drag. I'm not aware of any SEP that produces that much thrust. And even with an Isp >1000, your balloon still needs to carry a massive amount of propellant, as well as be robust enough to maintain structural integrity and not burn up during hypersonic flight.

Which is wrong. HOTOL was initiated in the mid 80's. Concorde goes back to the early 60's. Nobody at BAC or Sud Aviation the early 60's was considering SSTOs. None of the technology in Concorde is applicable to spaceflight. In those days, Europe was barely messing around with the Black Arrow and Diamant rockets. Skylon is only vaguely related to HOTOL in than Alan Bond worked on it. None of BAE's intellectual property was transferred to Skylon, which is a private venture completely separate from BAE. The whole concept is wildly different. This makes no sense. Delta wings were used for supersonic flight since the early 50's. The F102 Delta Dagger flew in 1953. The French Air Force were flying the Mirage III since 1956. Fly-by-wire was introduced on the Antonov ANT-20 in the 1930's. The most advanced material in Concorde was aluminium. None of those technologies were developed under some secret agenda to build an SSTO. They were developed because the industry needed them and then implemented in Concorde because they were state-of-the-art at that period.

This simply proves that you have no idea what you're talking about. By that logic, if you stick a rocket on a 747, you would get a Space Shuttle. The main differences are thermal requirements, attitude control, and of course, the massive amount of propellant that is required to acheive the dV. Nowhere in that article is it said that. Pretty much everyone in the late 50's was drawing up concepts of supersonic airliners. It seemed like the logical next step after the 707 and the Caravelle. Hence, SST was a dead end. So was the Chevrolet Corvair or the nuclear bomber. The junkyard of the history of engineering is full of bad ideas that seemed good at the time.

No it isn't. You need more than just wings and engines to make an SSTO spacecraft. There's quite a difference between an aircraft capable of flying at 2500 km/h and a spacecraft capable of reaching 25000 km/h. The biggest limiting factor for Concorde was its aluminium skin, which couldn't withstand temperatures above 126°C. This limited its speed to Mach 2.2. Huh? Sud Aviation had been working on a Super Caravelle since 1960, while BAC was working on its Bristol 223 since 1959. Both governments agreed to merge the two designs. Boeing only started serious work in its 2707 designs after the Concorde merger. HOTOL came 20 years later. It has no relationship whatsoever with Concorde. Most of the people who had worked on Concorde had retired by then and knowledge of hypersonic flight was way beyond what was available at the time of Concorde. Check out your timelines. Yet none of today's airliners use the same configuration as Concorde. One could argue that it was a dead end, like the Reliant Robin or the Chevrolet Corvair. Actually, I don't think there were many computers involved at all. Most of its design work involved slide rules, Rötring pens, and 1:1 plywood models. Nope, we're not going there.

Yeah, so magic then. If they actually had a propulsion system that could deliver an Isp > 1000s with a TWR > 1, why bother with an airship ? The aerospace industry, and even the military, would be scrambling to buy the patent.

Does it run on unobtanium or dilithium cristals ?

Carbon fiber didn't exist when Concorde was designed. Sabre engines have nothing to do with Concorde. You're utterly confused.

Prices aren't inherently higher than in the private sector. Actually, most of NASA's budget ends up going to private corporations. There is also the fact that government spending is an economical stimulus. Every dollar spent by governments ends up in someone's salary, and gets spent to buy other stuff and to pay other people. Some of it even goes back into the government's budget to get used again. When a government stops injecting money into the economy, things go bad. In the end, you either employ your highly qualified aerospace engineers to work for you on government contracts, which maintains and improves your country's technological capability and competitivity or you make them flip burgers at McDonalds or move overseas to work for someone else.

No it doesn't. You still need propulsion to accelerate from 0 to 25000km/h while fighting atmospheric drag. There still isn't anything better than rocket engines to that.

One of the big shortcomings of the N1 program was the lack of test firings. The first time each stage was tested was for the launch. They never bothered to build a test stand to test each stage before assembling the stack. The fact that the rocket was assembled in sheds in the middle of nowhere didn't help. The spherical design with an outer skin made it heavier than necessary. The whole effort was underfunded. Most people probably knew this, but the chain of command in the USSR didn't encourage honest bottom-to-top reporting.