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Comment Re:sunfire / in my stellerator / makes me... happy (Score 3, Informative) 98

There is also the element of funding for R&D. In the late 70's the DoE produced a fusion roadmap based on different funding levels. There was a crash program forcast which would have led to commercial fusion in 10-15 years, a robust development program that would led to fusion in 15-20 years, and a point where if funding remained below a certain level, would never lead to commercial fusion. Guess what funding level was chosen (well below the "fusion never" level). So the joke of "fusion is the technology of the future and always will be", is a result of no real investment being made. Sure ITER may be a $15billion project, but its also a 50 year long project. First announced in 1985, first plasma wont occur till 2025, that's 40 fricken years later, not exactly demonstrative of an intensive focus on developing fusion energy. Compared to what we invest in developing other sources of energy, its chump change

Comment Re:Common Sense (Score 1) 310

No, we had a fancy photo op and press release. Constellation had exactly the same problems, new President makes obligatory visit to KSC, makes a Kenneddyesque speech and never spends another second of his presidency thinking about it. We haven't had a president willing to invest political capital on space since Reagan (and even he didn't spend much)

Comment Re:Who is whipslash? (Score 1) 91

In most cases you're looking at within several hundred miles of the Florida or California coast (likely a bit further for Falcon Heavy core stages), we're not talking about the Grand Banks here. As well the stages are extremely bottom heavy (the vast majority of the mass is at the bottom of the rocket) and cylinders are good for deflecting wind loads (only cones are better). I'll also point out that so far, barge movement, pitching and rolling, has not been a factor in any of the failed landing attempts to date. I'm amused at the level of armchair quarterbacking going on here, people seem to think that the folks at SpaceX are complete morons and haven't thought of these very obvious concerns. We're not talking about brilliant insights here, just a lot of "I spent 15 min on Google, so I'm an expert" comentators

Comment Re:Who is whipslash? (Score 1) 91

So you're quite happy to spout "it will never work" without knowing much of the details.

Negative - you must have missed it in the post you are responding to. I'll repost that part again:

Never work? I never said that. I am certain that with enough money poured into the project, and making live landings of these things on barges in the ocean the actual mission, they will indeed work.

You said and I quote "Is going to fail then." period, full stop. (I assume you meant they are going to fail then, or it is going to fail then)

- Firstly the empty stages are extremely bottom heavy as all the engines, thrust structure and plumbing are located at the base. The only mass up top are empty tanks.

I've noted that at landing, most of the mass is in the bottom. Are you just pissed that someone takes a contrary opinion? Re-read what I wrote. But the question is how much of that mass is above the triangle formed by the landing gear? I dunno. I ask. Is the answer that I shouldn't ask?

There is nothing wrong with having a contrary opinion, provided its an informed opinion. You've pretty much told us that "Is going to fail then.", but admitted that you don't really understand what SpaceX is doing, how their going about it, or the design of the Falcon 9. It's not like you need to dig that deep for much of this information. The answer is yes, most of the mass is below the triangle formed by the landing gear. The lower attach point of the landing legs is on the thrust structure where all of the engines are attached. The upper attach point is on the base ring of the lower tank.

Another issue is fuel sloshing while pitching and rolling. They may have taken care of that.

If you don't know what they've "taken care of" you may want to avoid making blanket statements of "Is going to fail then." or about how far away they are from successfully landing a stage on a barge.

- Secondly, the barges when flooded are extremely stable, being able to maintain themselves within 3m even in heavy storm conditions.

Well now 9 feet pitch and roll is not "extremely stable". Regardless, at what sea state is this 9 foot pitch and roll achieved? For at least my outlook, I would prefer an active stabilization system on the barge. I'd be concerend a lot about that 9 feet pitch and roll movement after landing as well.If you are above sea state 5, could be a little saltwater ingress into thos reusable engines. I suspect however that stormy seas would be a mission abort factor.

You know what, 3m is also 3000 mm (sounds much bigger), and this is in sea states of 7-8 or storm conditions which is also as you indicated a "mission abort factor". Again you are making "predictions" about topics you don't really know much about. The ADSD's are actively stabilized, each fitted with 4 x 220 kW azipods

- Thirdly, there are many missions where a return to launch site isn't possible. The center core on a Falcon Heavy is too far down range to return to land. For large GEO sats, there isn't enough fuel to both launch the sat and return to launch site (RTLS reduces the mass to orbit on a Falcon 9 by 30%). So they MUST land on a barge if they want to reuse these stages

I'm not so certain that that argues against anything I've said. Seems to me that they aren't going to be able to reuse all their rockets then.

For what its worth, One of my most valuable traits while I was working was that I didn't take the "Hey - it's all worked out, and this will work great!

Because all of the YesMen become redundant when they have no ideas after the things that were a lead pipe cinch didn't work. People did eventually listen to me because so many times, what I asked about turned out to be an actual problem.

Buy hey, if you said this thing works, just let Musk know, and they can go into full ocean barge recovery of every launch, because Hey! it works-and who are asswipes like me to ask questions? Never ask questions or show any doubt. It's all good, as witnessed by the 100 percent barge recovery success. Oh...wait...

You know what is just as bad as a "yesman", a "noman", someone who says "is going to fail then." when they self admittedly don't know much about the topic at hand. Its called being an armchair quarterback. It's one thing to say, "I know they've had hundreds of engineers working on this for years, but I spent 15 min on Google so I'm obviously qualified to call them idiots", vs. "I am one of those engineers who've worked on this for years and have a legitimate concern". These are not some kind of deeply insightful observations you alone have made. These are pretty much on the same level a 15 year old spouting that NASA was dumb for never flying the Space Shuttle to the Moon to take pictures of the Apollo landing sites. I don't need to convince Musk as he's spending his own money to do this very thing, and much of his business model is predicated on barge recovery of the Falcon 9 No one has claimed that this is a trivial exercise, but each attempt has gotten progressively closer, they are clearly demonstrating progress. Will the next one be successful, maybe, maybe not

Comment Re:Who is whipslash? (Score 1) 91

So you're quite happy to spout "it will never work" without knowing much of the details. - Firstly the empty stages are extremely bottom heavy as all the engines, thrust structure and plumbing are located at the base. The only mass up top are empty tanks. - Secondly, the barges when flooded are extremely stable, being able to maintain themselves within 3m even in heavy storm conditions. - Thirdly, there are many missions where a return to launch site isn't possible. The center core on a Falcon Heavy is too far down range to return to land. For large GEO sats, there isn't enough fuel to both launch the sat and return to launch site (RTLS reduces the mass to orbit on a Falcon 9 by 30%). So they MUST land on a barge if they want to reuse these stages

Comment Re:Who is whipslash? (Score 1) 91

Teams from the nearby tug will board the barge and tack weld cleats onto the landing legs, securing it to the barge. There will be no cranes involved until they return to port to remove the stage, although Elon has proposed that further down the road, the stage will simply be secured, partially refueled, cleats removed and "hop" back to land.

Comment Re:Judgement (Score 1) 329

Not at all, when I buy tools I judge how frequently I'll need them. I use my table saw regularly so made the investment on a high quality cast iron model. I only expect to bend copper pipe a few times in my life, so I didn't spend a lot on high quality pipe benders. Still cost way less than hiring a plumber to come in and hook up my dishwasher

Comment Re:Aaaaand.. (Score 1) 248

One problem is that people don't jump from low-skill to high-skill instantaneously. We're building a situation that there are few entry-level jobs for new-grads which allow them to start developing the skills they need to get those "high-skill" jobs. In 20 years when we're all retired, who's going to replace us?

Comment Re:TL;DR (Score 2) 189

The Saturn program (Saturn I, IB and V) had virtually zero relevance to developing ICBMs. They used the wrong fuels, were not rapidly available, and were far too large and expensive. While Mercury and Gemini did make use of Atlas and Titan, it was primarily because they were the only large rockets currently available in the US arsenal. The USAF was investing plenty in ICBM research without the need for a "cover"

Comment Re:Good thing ULA was there (Score 1) 114

Ok, I'll give you the common engine between the Atlas V and the Atlas 3, but the tanks (material, diameter and construction), thrust structure and avionics are completely new with Atlas V. The Atlas 3 wasn't even designed to use the solid boosters frequently used with Atlas 5. It doesn't even use the same launch pads at CCAF and SLC-3E had to be completely rebuilt to support it. Lockheed clearly played down the differences during the EELV process as a way of leveraging the "long" history of the Atlas program

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