An ex-SpaceX engineer has a design for a nuclear-powered rocket that could beat SpaceX's BFR on $/kg and many other aspects:
John Bucknell says the nuclear turbo rocket technology and his designs are ready for development. The air-breathing nuclear thermal rocket will enable 7 times more payload fraction to be delivered to low-earth orbit and it will have 6 times the ISP (rocket fuel efficiency) as chemical rockets. The rocket will have two to three times the speed and performance of chemical rockets for missions outside of the atmosphere. [...] Besides being cheaper and vastly higher performing that the SpaceX BFR, the Bucknell Nuclear turbo rocket will to do things which the SpaceX BFR cannot.
Bucknell's proposed air-breathing nuclear thermal rocket propulsion cycle called the Nuclear Thermal Turbo Rocket (NTTR) improves payload fraction to Low Earth Orbit (LEO) by a factor of 5-7 relative to State of the Art chemical rockets.
Mission Average Specific Impulse: 1430 to 1788 sec (About 5-6 times better than 350-400 ISP chemical rockets)
The Nuclear Thermal Turbo Rocket (NTTR) is a supercharged air-augmented nuclear thermal combined cycle rocket architecture. Nuclear turbo rockets already offer the highest Specific Impulse (Isp) of launch-capable pure rocket propulsion systems, whereas launch to hypersonic turbine combined cycle systems offer far higher Isp. The NTTR combines both modes.
Also at Ars Technica.
See also: John Bucknell designer of the Nuclear Thermal Turbo Rocket is answering questions
Turbo Rocket Economics are $85/kg to LEO or $715/kg to Luna
(Score: 4, Insightful) by bob_super on Saturday July 14 2018, @01:28AM (1 child)
We have something that works reliably, and only occasionally goes boom.
And now some guy wants to replace it by a solution with the word "nuclear" attached. The benefits are ... good, but not overwhelming.
Not happening.
(Score: 2) by legont on Sunday July 15 2018, @03:15AM
Yeah, Russians and/or Germans have to do it first; than we employ them.
"Wealth is the relentless enemy of understanding" - John Kenneth Galbraith.
(Score: 0) by Anonymous Coward on Saturday July 14 2018, @01:53AM (5 children)
...and when it blows up an ascent, how much of the Earth's surface will be contaminated and for how long with that be uninhabitable?
-- OriginalOwner_ [soylentnews.org]
(Score: 1, Informative) by Anonymous Coward on Saturday July 14 2018, @02:14AM (4 children)
All launches will be over the airspace of poor people and socialists. Finally, billionaire libertarians will inherit America like God intended.
(Score: 0) by Anonymous Coward on Saturday July 14 2018, @03:43AM (2 children)
Seems likely.
and socialists
Good luck finding any of those--much less a cluster.
billionaire libertarians will inherit America
Looking around, I'd say that your verb tense is wrong.
-- OriginalOwner_ [soylentnews.org]
(Score: 0) by Anonymous Coward on Saturday July 14 2018, @04:21AM (1 child)
Do not worry. If they are needed, some will be simply assigned. No proof required anymore.
(Score: 0) by Anonymous Coward on Monday July 16 2018, @11:02AM
... after the fact
(Score: 4, Funny) by SanityCheck on Saturday July 14 2018, @06:34AM
Sure they may be present at the location, but it will adversely impact whomever's land they are squatting.
(Score: 5, Informative) by Runaway1956 on Saturday July 14 2018, @02:03AM (4 children)
"Air breathing rocket" is an oxymoron, right? So, what have we seen before that resembles the description in the article?
https://en.wikipedia.org/wiki/Project_Pluto [wikipedia.org]
http://www.mragheb.com/NPRE%20402%20ME%20405%20Nuclear%20Power%20Engineering/Nuclear%20Ramjet%20and%20Scramjet%20Propulsion.pdf [mragheb.com] (See the PDF in the URL?)
(Tried a longer quote, but the formatting in borked, sorry.)
As I recall, the real problem with these things was, you can't land them. They are hot, hot, hot, and you just can't land them anywhere. As soon as they slow down for an approach to an airport, the fire is snuffed, so they have no power, making it difficult to land. They were also very radioactive, so no airport would grant permission to land. A couple of them flew, and were crashed into the ocean, but I don't see references to them in my quick search.
Cure the radioactivity problems, and, sure, these things can almost certainly reach orbit. They better be at least as aerodynamic as the space shuttles, so they can land without power.
(Score: 2) by driverless on Saturday July 14 2018, @03:41AM
Pluto as a space launch system (rather than the pipedream cruise missile, look up Supersonic Low Altitude Missile for where that went) was a bit of a problem in that by the time they got the engineering problems mostly sorted, and remember this was with technology from half a century ago not with what we've got today, people had lost interest in it, they just built bigger chemical rockets. I'm surprised it's taken this long to be revived, it was quite viable technology, particularly with half a century of extra progress in materials, computer modelling, etc. In terms of how to land them, you don't, you loft the payload into orbit and then the prime mover continues outward into someone-else's-problem territory.
(Score: 1) by khallow on Saturday July 14 2018, @04:01AM
Especially if something breaks and you can't turn them off.
(Score: 0) by Anonymous Coward on Saturday July 14 2018, @04:36AM (1 child)
If ever there was someone who can make a ridiculous URL, it's that guy.
(A prime opportunity for you to have made a proper hyperlink.)
-- OriginalOwner_ [soylentnews.org]
(Score: 0) by Anonymous Coward on Saturday July 14 2018, @03:33PM
> A prime opportunity for you to have made a proper hyperlink.
To Google [google.com], presumably.
(Score: 1) by anubi on Saturday July 14 2018, @03:19AM (5 children)
I am a little confused... as one leaves our atmospheric layer, the air becomes thinner and thinner, approaching zero density.
Does that mean it gets harder and harder to collect enough mass to shoot out the other end?
How does this thing work in a vacuum?
Or, do they still carry some sort of mass to throw out the back of the thing to make it go?
"Prove all things; hold fast that which is good." [KJV: I Thessalonians 5:21]
(Score: 2) by Knowledge Troll on Saturday July 14 2018, @03:28AM (2 children)
I was having a hard time with The rocket will have two to three times the speed and performance of chemical rockets for missions outside of the atmosphere considering it says it is an air breathing engine. However in the article is this:
I believe that means they bring reaction mass with them and use it when the atmosphere can't provide enough. Though the entire article looks like marketing garbage because it says something like "this rocket is 7 times better than SpaceX" which is unquantifiable and that it'll make space based solar power technology 3x most cost effective.
I'm not a power plant engineer or a rocket engineer but I would be surprised if launch costs were the barrier to entry for space power generation using photovoltaic cells. That seems awfully optimistic.
(Score: 2) by Hartree on Saturday July 14 2018, @04:43PM (1 child)
Actually, launch cost is the biggest barrier to space based solar (assuming you don't run into political problems which can derail anything). You have to get massive amounts of materials up there to build the solar sats. Once you get the solar cells up and running they tend to last well, so they can pay themselves off.
In fact, the launch cost is so much of the problem, that people have advocated getting the materials to build spaced based solar from the moon as the amount of gravity you have to overcome is so much smaller.
(Score: 2) by Knowledge Troll on Saturday July 14 2018, @05:55PM
Thanks for sharing - it'd be nice if that page is not hyperbole - I would really like 2 cents per kw-hr electricity and SSTO rockets.
(Score: 1) by khallow on Saturday July 14 2018, @04:05AM (1 child)
Probably. After all with that nice ISP, you'll probably want it to operate in space too. Depends I think on whether you can throttle it back (that is, reduce the thrust substantially). Low thrust but high ISP is a viable approach in space travel.
(Score: 2) by deimtee on Saturday July 14 2018, @07:00AM
Isp depends on the temperature of your exhaust and inversely on the molecular mass. NERVA threw nice hot H2 gas and got an Isp of about 1200.
If he's getting 1400~1700 then it's either substantially hotter, or more likely, that Isp includes the bonus thrust from airbreathing. I would expect that in-vacuum thrust would use an onboard tank of H2 or He and get about the same as NERVA.
If you cough while drinking cheap red wine it really cleans out your sinuses.
(Score: 4, Informative) by Knowledge Troll on Saturday July 14 2018, @03:21AM
Which is just a big ass radioactive complicated version of the plastic air pressure rockets we played with as a kid. https://en.wikipedia.org/wiki/Nuclear_salt-water_rocket [wikipedia.org]
(Score: 0) by Anonymous Coward on Saturday July 14 2018, @06:22PM (1 child)
Last i heard, nuclear aircraft propulsion was still banned. ( and since its taking off from the ground, it would qualify as aircraft )
(Score: 0) by Anonymous Coward on Tuesday July 17 2018, @08:55PM
Where did you hear of a ban? I haven't heard that. I looked at a relevant Wikipedia article and it lists projects that were "abandoned," "terminated" or "cancelled." https://en.wikipedia.org/wiki/Nuclear_aircraft [wikipedia.org]