Bill Phil

What even is this thread?

Once I had to return Jeb from the Mun. He got stuck in kerbin orbit with no jetpack fuel... that rescue was hair-splitting...

It's Nuclear Space Propulsion by Holmes F. Crouch. An excerpt can be found on Atomic Rockets here: http://www.projectrho.com/public_html/rocket/realdesigns2.php#id--Reusable_Nuclear_Shuttle--Lunar_Ferry

We were also supposed to land on the Moon in 1967 (originally, maybe even earlier) and be in orbit of Jupiter by 2001... Apollo technology could not do a Mars mission. New tech would've been required, but that could've been developed. Mars missions were expected by the late 70s or early 80s if everything went to plan.

Launched an SSTO not too long ago. Turned out it could go to Minmus, so I took it there.

It only required an extra 900 m/s, far from requiring 2 to 3 times the fuel. Maybe 12% to 15% more propellant with an NTR, but the design called for a margin with over 900 m/s regardless. Reducing the time is significant. Less complex/expensive life support is required. Less exposure to the reactor and less exposure to radiation in space. Less isolation for lunar bases and the like, only a day away from Earth. Less problems with boiloff. Certainly advantageous. Chemical rockets would be hard pressed to come close. This also wasn't intended as a stunt, but was proposed for general use. Time is the enemy in space, once everything else has been sorted out.

I read somewhere that NTRs can get lunar transfer times down to less than a day and still have performance to carry a well sized payload. Reducing time certainly has major advantages.

And even then it would take centuries with a realistic amount of engines. They do it in half a generation. Sorry, but no. Ceres is not a spaceship, it's far larger. And also, that fusion drive has some problems of its own...

That is really strange. I looked earlier and it was not there...

And notice how many problems that's caused? The happier they are the less likely they will be to try and revolt. Bread and circuses. Not only that but the sheer cost of spinning up Ceres is just plain ridiculous.

Timberwind claimed high T/W ratios, although from what I can find the whole project was very sketchy. Regardless, a LANTR can increase thrust significantly and allow launches using NTRs. At the cost of specific impulse, and an increase in complexity.

https://en.m.wikipedia.org/wiki/Poly(methyl_methacrylate) Used in submersibles from what I can find.

So like a procedural video? Cool.

If I recall, there is a transparent material that increases strength when under pressure. Probably wouldn't help against big sharks, though.

That was the plan. But it never got executed. It was viewed as dependent on the Shuttle program, which didn't live up to expectations, and it was shelved until the Shuttle could support it, which it could never do. You'd need a true super heavy lifter to take full advantage of NTRs (if you can't get high flight rates, that is) and that seems to be on the horizon.

Air drag is usually a very small loss, while gravity drag is far worse. Air drag is a function of air density, velocity, reference area, and coefficient of drag. Two of those depend on the rocket's shape, and one is a function of time and the other a function of altitude. It can be done, and is, but there are a lot of variables involved. Just give yourself a good margin.

They're heavy, although they do provide high isp. It depends on size of payload and total delta V. There are many circumstances where a nuclear engine is preferred and where a chemical engine performs better. As for why not... well, NERVA was almost flight ready by the time it was cancelled. Probably something to do with commitment and money.

That's not good. Voyager was great...

Interesting. Jupiter may have messed with it, but it is possible that it's not from this system... Can't argue with a name like that.

Rocket assisted landing, anyone? Duna is a bad place to practice for Laythe. Kerbin works much better.

Whoa. Nearing 2K now...

That's what I said. The SRBs were essentially failing but they were not below their certified temperature range before launch. Even so, the SRBs were failing all the same. It just so happened to not be a mission LOCV failure until Challenger. The cold exacerbated an already existing issue.

Oh. You mean this song: It's in so many trailers....

The 5-segment SRBs SLS will use are not the Shuttle SRBs with an extra segment. They look similar, sure, but they are not. They've been redesigned. They're not the same at all. Completely different, save for propellant used. So long as the LES can pull the capsule away far and fast enough there's not too big of an issue. The problem with Shuttle was being next to the stack. If the SRBs prove to be an issue during a launch they'll abort and the crew should be pulled away safely. The boosters showed problems before the first launch, but they used them anyways. Before the Challenger disaster, the SRBs were essentially failing in the exact same way, with the only difference being them not below their certified temperature range before launch, and thus the mission was able to continue unimpeded. This happened 7 times out of 9 launches in 1985. If they had been affected in the same way in one of those launches, the disaster could've happened earlier in the program, potentially as early as STS-2. Thankfully that design problem was eventually addressed, but had that disaster not occurred, imagine the same failure during one of the "death star" missions. Hydrolox in the cargo bay. And that was scheduled for the same year as STS-51-L. No matter what, spaceflight must be handled responsibly. Design compromises can easily lead to failures that can cause deaths.

From what I can find, jet fuel (not sure which particular fuel...) and RP-1 can be refined in the same refineries. What really drives up price is the high quality input stock that comes from a small number of oil fields, and of course the small market.