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Nuclear pulse propulsion Mars mission spacecraft in LEO.
Image featured: on Winchell Chung’s Atomic Rockets site, Project Orion page, under William Black's 3D Orions.
Circa 1964 Nuclear Pulse Propulsion Mars mission spacecraft modeled in high detail from specifications in Nuclear Pulse Space Vehicle Study GA-5009, Vol. III – Conceptual Vehicle Designs and Operational Systems, PDF here: GA-5009 vol III (PDF), prepared at General Atomics John Jay Hopkins Laboratory for Pure and Applied Science for George C. Marshall Space Flight Center’s Future Projects Office.
This is the NASA Interplanetary Exploration version of Orion, greatly scaled down from the 4,000 ton Earth surface launched General Atomics reference design, manned by a crew of 200, which would have been capable of reaching Mars in four weeks and orbiting Saturn’s moon Enceladus in seven months.
Here, two spacecraft imaged on orbit, immediately prior to departure. Within the bi-level shielded powered-flight station aboard each spacecraft the eight man crew performs final system checks prior to firing the 10-meter nuclear pulse propulsion system for a 72,850 fps trans-Martian burn, departing Earth orbit on a 450-day Mars mission.
The spacecraft are 160 feet long with a departure weight of 1,633,625 pounds.
Each spacecraft carries three 2-man MEM’s (Mars Excursion Modules), mounted inside protective canisters, along with an Earth return capsule and its maneuver-stage. Mounted adjacent to the powered-flight station, above the crew-habitat, each vehicle carries two, 2-man, pods used for close in post-burn visual inspection of the pusher-plate and shock-absorber system, as well as lesion between the spacecraft in flight. In the event of a failure of one vehicle the 2-man pods would be used to evacuate the crew to the surviving spacecraft.
In transit the spacecraft would rotate end-over end around their short-axis in order to generate centrifugal gravity.
The powered-flight station of each vehicle (the uppermost portion of the spacecraft) is outfitted as solar storm shelter with 90-day emergency supplies and fitted with escape-motors so that in the event of system-failure it can cast-off from the main vehicle, acting as a life boat, the mission-abort escape vehicle has a post-escape 2,000 fps ΔV maneuver capability.
GA-5009, Vol. III is one of the final reports on Orion, 174 pages of exhaustive technical detail, vehicle concept diagrams, and detailed nuclear pulse propulsion reference missions for 8-man, 20-man, and 50-man Mars and Jovan explorations (as well as, interestingly, a 1 million pound payload nuclear pulse Earth orbit to lunar surface ferry). Because these are conceptual vehicle designs some minor details are discussed in the technical data, but left off the diagrams – I’ve added these details to the model as logic dictates. Added detail includes the high-gain dish antenna, a docking node for the returning MEM’s (sourced from NASA’s 3D model archive, this is the same pressurized mating adapter used on the ISS) and a protective bay containing the Earth return capsule mated to its Earth approach maneuver stage.
Pressurized-mating-adapter 3ds file courtesy of NASA 3D model Archive.
Earth back-drop courtesy NASA/JPL.
Orion: In Flight
Indeed, Orion was a great smashing idea, nothing even dreamed of since could loft the sheer tonnage (literally thousands of tons per launch) of payload out of the gravity well – of course I refer to the General Atomics reference designs. These were in the 4,000 ton range, 101 feet in diameter and 196 feet long—although the design could be scaled to nearly any size required. Freeman Dyson (who worked the thermal fluid dynamics of bomb-generated superheated plasma striking the pusher-plate thousands of times in boost phase) set the upper limit for Orion at an 8 million ton vehicle more than 2,000 feet in diameter. The NASA-Exploration Orion pictured here is scaled to fit on a Saturn-V booster, it would carry a crew of 8 with a departure weight of 1,633,625 pounds. The General Atomic reference designs would carry crews numbering between 50 and 200 on interplanetary exploration missions.
For more information on Orion see my journal entry on nuclear pulse propulsion, here: Orion: Nuclear Pulse Propulsion.
The USAF Orion Battleship was a 4,000 ton design, approximately 120 feet in length carrying a crew of about 100—and yeah, it scared the pants off Kennedy when he viewed a display model. The thing is bristling with guns, cannon, and and missile launchers. It looks like a doomsday weapon, which it is, it's designed to be an element of a space based nuclear counter-strike deterrence force. In the event of a nuclear confrontation the spacecraft would be recalled from deep space to rain down nuclear devastation on enemy territories. See Winchell Chung's page here: Project Orion Battleship.
The Cold War was a different era. I’m old enough (and was well informed enough at the time) to understand just how thoroughly terminal a total-forces confrontation between the U.S. and the old U.S.S.R would prove to be.
I’m not making an argument for it, but I can understand the tactical/strategic advantage of having a fleet of Orion’s staged out at the lagrange points, they’d be an unassailable retaliatory force, and could be recalled to LEO real fast.
Each was to carry 500 twenty-megaton city-killer warheads and assorted other weaponry including several hundred Cassaba-Howitzer, a shaped charge nuclear directed energy weapon. Cassaba-Howitzer would be perfect as an anti-ballistic missile defense. One hit by a Casaba Howitzer and a Soviet ICBM would be instantly vaporized. Which is why project Casaba-Howitzer's name came up a few times in the 1983 Strategic Defense Initiative.
As Winchell Chung points out: a Casaba Howitzers fired from orbit at ground targets on Terra would be inefficient, which is not the same as "does no damage." A nuclear warhead fired at a ground target would do far more damage, but the Casaba Howitzer bolt is instantaneous, ("instantaneous" meaning traveling at "a recognizable fraction of the speed of light") non-interceptable, and would still do massive damage to an aircraft carrier or even a sub providing it was at a very shallow depth—which Soviet subs would be, just barely breaching the ocean surface, when prepairing to launch, or launching, nuclear missiles.
Scott Lowether, Aerospace Projects Review, estimates that each Casaba-Howitzer round would have a yield "up to a few kilotons" and could deliver close to 50% of that energy in the spear of nuclear flame. Winchell's math says: Three kiltons is 1.256 × 1013 joules, 50% of that is 6.276 × 1012 joules per bolt.
A few years back Lowther started working on “Nuclear Pulse Propulsion,” which is to be the comprehensive tome on nuclear pulse propulsion, and had the idea to include a short fiction work on the Orion Battleship into the tome, the result is a (rough, rough) draft telling the tale of Orion orbital Battleships going full commitment against Soviet forces—it’s rather grim, but an interesting short read. Lowther is one of the go-to experts on numerous aerospace projects, so this is probably as realistic as it can get. If you’re interested his Orion Battleship Tale, PDF file, can be had for free here Battleship Tale.
that's an atmosphere that's impossible to explain to people who weren't born then.
I read a lot of articles and papers on the Orion and the proposal sent to Kennedy some time ago. Interesting and scary stuff, but it did make sense at the time.
I dunno if I'd personally call 'a few kilotons' inconsequential. That'd make someones day miserable enough.
snagged the pdf, thanks, that'll make a good read.
document available here
It has to be both powered flight station and escape vehicle, since the lower habitat module is designed "with the chairs on the ceiling". This is due to creating gravity by the "tumbling pigeon" concept, where the spacecraft spins head over heels so to speak.
In this document
on page 47 it says the escape rockets are little sold-fuel thrusters, while the post escape rockets are liquid fueled.
Details about the emergency escape vehicle are on the following pages. The Wikipedia image shows the 10 man Orion escape vehicle, the document shows both that and the larger 20 man Orion escape vehicle.
The vehicle is accessed by funny tube on the side. This is because the floor of the escape vehicle is solid radiation shielding. Any holes for access tunnels would allow radiation to enter during normal operations while the nuclear pulse units were being detonated.
Well, the Orion is propelled by nuclear explosions, after all.
It does mention that in theory one could avoid the side access tubes if you had doors on the bottom with radiation shielding. But this would make the doors so thick they would be difficult to open.
The second link does have lots of nifty diagrams and cut-away views. I'm not sure how well it will help modeling the Orion in Kerbal Space Program, but it will give you some ideas.
For the flight station, I can see the tubes would also give some clearance in allowing the escape rockets to fire without creating hazardous debris.
Also, I'm not modeling anything for KSP! I'm only using your mod to build replicas of the General Atomics designs, just want to be clear. Your Orion Drive is already perfect anyway! Any plans to continue work on it as future updates are released?
An image of a basic 10 meter design built in KSP is already in my gallery too. However, it has no access tubes as I couldn't figure out a way to connect them to the crew quarters hab.
I know I should be working on adapting the Orion mod to the new versions of KSP, but alas life keeps getting in the way.
Hey, that’s very cool.
I believe the powered flight station was intended as an in-flight emergency life-boat – I am not entirely certain it was intended for a launch-abort scenario. The main worry stated in the report was the possibility of a fire in the propulsion module or some other catastrophic failure which necessitated abandoning the main vehicle and the concern in this event was the need to alter the life-boat’s trajectory. 2,000 fps ΔV maneuver capability would allow the powered flight-station to move away from the disabled spacecraft and alter trajectory as necessary to prevent collision with it or some other body.
In all mission scenario’s spacecraft would travel in pairs, and the space-taxi’s would allow rescue of crew from a disabled vehicle, some mission abort mode’s for Terra-return in this scenario were considered in the reports. I’ll note Nyrath and see if he can add more or clarify on this.
Have you seen Rhys Taylor’s newest Orion animation?
A nuclear pulse propulsion version of the spacecraft “Discovery” from 2001: A Space Odyssey. Orion Discovery
Also, yes I have seen DrRhysy's video! It was great, definitely what the Discovery should have looked like in Kubrick's film. Although, one must wonder what HAL might have done if he had all of those nuclear bombs at his disposal.
Indeed I have, many times. My post Over Mars is a visualization of a nuclear pulse battleship inspired by Larry Niven’s Michael. In the thread on that post Winchell Chung (NyrathWiz on DA) talks about working with Aldo Spadoni, aerospace engineer and conceptual designer who collaborated with Larry Niven on designs for ”Michael" and the creation of a detailed Blender mesh of the ship, which is yet to be released.
But I must interject: Mars was nothing. The 1959 design for the advanced interplanetary Orion was capable of carrying a payload of 1,300 tons (not pounds) to the Saturnian moon Enceladus and back!
The advanced interplanetary Orion was intended to land an exploration crews consisting of over 100 mission specialists on targets including Enceladus, Callisto, and Mars.
In the bargain , the advantage of Orion as an HLLV is unmatched by any other launch system.
I was annoyed that they had a miserable NERVA solid core nuclear thermal engine, but nothing stronger. So I made a mod for the game, adding a Orion engine.
I based it on the USAF Orion with a ten-meter plate.
Actually playing with it in the game gives one an intuitive feel for the Orion. It has shocking amounts of delta V, and can lift huge amounts into orbit. But one has to construct very sturdy spacecraft or the shocks from bombs will rapidly shake the spacecraft to pieces.
But I did find some surprises with my Orion module. Stock Kerbal ships use tanks of liquid hydrogen/liquid oxygen, which has a relatively low density. So a few attitude jets suffices for a reaction control system.
The Orion, on the other hand, as per the USAF study, uses magazines containing 60 nuclear charges, each charge is 141 kilograms. I dutifully encoded this into the mod. To my surprise I found that the inertia of all that mass was tremendous, you need large arrays of attitude jets or your ship will only turn ponderously slow.
And as you pointed out, fallout can be drastically reduced by using a large armored launch pad with a dusting of graphite
True the Orion can be boosted on top of a Saturn V, but most of the point of using Orion is for surface-to-orbit heavy lift. That is what it is optimal for.