PARIS Launch System

PARIS Parallel Rocket launch System
'PARIS' can be taken as an acronym for Parallel Rocket launch System, Parallel Rocket Integration System, or Parallel Rocket-Ignition System.

Basically, in its original form, the idea is the product of combining the Delta IV Heavy growth options to the Ares V core stage.

All tanks and engines burn from the beginning until the tank is spent. This dispenses the need for ullage engines, and ensures engine reliability.

Using extended versions of the Shuttle External Tanks, a Paris VII launch vehicle will just fit through the VAB doors with about 3-inches either side.

This is probably the biggest rocket possible that can be easily assembled in the VAB, transported on the crawler, and uses current tank and engine designs.

Such a rocket may be the cheapest and quickest route to a 500+ tonne class launcher possibly required for a 'killer-asteroid' interception mission.





The system above assumes Hydrogen/Oxygen propellant with a cluster of 7 RS-68 engines underneath each tank.

A Kerosene/Oxygen version could use either a cluster of 7 RS-84 engines, or cheaper Russian RD-170 engines in clusters of 4.

The latter system would work as below (each RD-170 engine has 4 rocket nozzles):



Such a launch vehicle would produce about 7 times as much thrust as the Saturn V on lift-off. It would also be about 7 times as heavy. Therefore, at best it may lift about 7 times the Saturn V's payload, or 900 tonnes.

Comments on the PARIS Launch System can be added here.

I am also happy to answer any questions.

Might it be possible to add 6 SRBs to the design to increase lift capacity?

Also, is it possible for the PARIS VII to carry the "2nd stage" tanks into orbit the way that the shuttle can? If so the tanks can be used to quickly build pressuriseable space in orbit.

As discussed on the newmars.com forums, the problem with SRB's is their massive dry weight which makes them difficult to transport.

Remember that the enormous Paris VII would only weigh about half of the shuttle launch stack, and therefore would be easy to transport around, even on the existing transporter-crawlers.

In contrast, just 6 (5-segment) SRB's by themselves would weigh about 5 times as much as the shuttle launch stack.

In all versions of the Paris Launch System discussed so far, the core tank achieves orbital velocity in a similar manner to the external tank of the Space Shuttle, and can therefore be used as a pressurizeable space habitat.

I just thought of a method that could be used to launch it (the following applies to the Paris VII configuration):

Imagine that the triangular space between each tank is filled with solid metal (bare with me for a sec) from the top to bottom. Six of these strucutres will act to connect the tanks together, and they also reinforce the whole launch vehicle. Now imagine that these metal structures are bored from the top down along half their length. The bottom half is similarly bored upwards, but with a slightly reduced bore diameter, until the tubes are connected. The smaller bore at the bottom is then machined with a set of grooves, similar to an internal screw thread. However, once this is done, opposite sides of the grooved bore are machined so that they are flush with the bore of the top tube (i.e. the top bore is extended through the grooved bore in two lines) so that half of the grooved area is removed.



Now, round steel columns will be fitted within each tube.
The lower half of each column will be thinner than the top, encased in insulating concrete, while the top half of the steel column will be machined with a matching array of grooves. These grooves will again be machined in a similar manner, so that they interlock with the inside of the lower tube, but can slide freely within it if they are turned a quarter-turn. A smaller section at the bottom of the column will also be machined with these grooves.

At the very top of each column will be a piston which can slide freely within the upper half of the tube and seals against it. Once the columns are fitted by lowering them through the top of the tube (with the column turned a quarter-turn so that it can slide all the way in), a cap is fitted to the top of each tube to seal it. This then creates an air-tight cylinder from which the column can act as a piston.



For additional support, another six tube and column assemblies can be mounted around the periphery of the launch vehicle. Now, at this point I should point out that these tubes will probably not be made out of solid metal, but rather some sort of lighter-weight design will be used.


This is how the vehicle might be assembled in the VAB:

First, a few tube-and-column assemblies are mounted upright onto the MLP platform. For each column, there will be a short bore with interlocking grooves bored into the MLP platform directly beneath it. This is so the bottom section of each column can be lowered into it, and when quarter-turned, they will lock with the MLP. Once a few tube-and-column assemblies are affixed to the MLP, the huge tanks (complete with engines) can be brought in one at a time and bolted to the tube-and-column assemblies. Thus the columns will act as supports as each tank is added, keeping their engines off the ground.

Once all 12 tube-and-column assemblies, and all 7 tanks (including payload), are affixed together, the completed launch vehicle can be rolled out of the VAB using the existing crawler-transporters.

Now heres where it all comes together:

Once the vehicle reaches its designated launch site, the crawler transporter stops, and compressed air is pumped into the top of each tube. At this point, the columns are still locked within the tube and the MLP, but once sufficient pressure is built up to support the dry weight of the launch vehicle on air pressure alone, each column is turned a quarter-turn, unlocking them. Air continues to be pumped so that the vehicle is eventually lifted right into the air; so far that the piston at the top of the column is at the bottom of the upper (smooth-bored) tube. At this point, the columns are again turned a quarter-turn, locking them to both the MLP and the launch vehicle.

All of the vehicles 49 engines are now so far up in the air (maybe 40 meters above the surface of the MLP) that there will be no need for blast diversion channels or any sort of permanent launch pad structure (although a traditional launch tower will probably be maintained for crew loading, systems monitoring, fuel management, and the like).

With all 12 columns locked to the MLP and vehicle, the fuel tanks can now be filled in preperation for lift-off. All 49 engines can then be tested for a few seconds while the columns hold the vehicle down. If all engines are go, all 12 columns are quickly quarter-turned (perhaps explosively); instantly releasing them from the launch vehicle.



To aid their quick release, the grooves may be helically cut at a 45-degree angle: perhaps clockwise at the bottom and anticlockwise at the top, so that when they are turned, the acceleration of the vehicle provides some of the force needed to turn them, and also so that the columns remain anchored to the MLP when they are unlocked from their tubes. Also, the pistons at the top of each column will be designed to safely shear off when the launch vehicle is released.

The four first-stage tanks will each bring with them 2 tube assemblies, and 2 extra engines (in addition to their own 7 engines), when they are spent and released. The two second stage tanks will shed the remaining 4 tube assemblies, so that the middle tank carries no additional mass to orbit.

Here is the tube and column arrangement diagram overlaid onto a revised engine fuel feed diagram:



In this arrangement, there are 3 first-stage tanks, each with 11 engines, 3 second stage tanks, with 5 engines, and the middle tank burns continuously on a single engine.

Most importantly, I've now concluded that it would be simplest if the engines that are fed off the first stage tanks (green) are dropped with the stage, rather than using explosive knives to cut the fuel lines (which would have left the extra engines as dead weight). Likewise, the engines which feed off the second stage tanks (yellow) are also dropped with the stage.

I'm not sure if this design is optimized. Perhaps only one engine for the middle tank is not enough. Although shedding the previously dead-weight engines should improve performance a bit.

Reviewing the various possible engine fuel-feed arrangements is what led me to conclude that dropping dead engines away with the spent stage was the more simple solution. Looking at the diagram above, you can see how the auxilliary first stage engines would easily 'peel' away from the bottom of the second-stage tanks. These auxilliary engines would be structurally attached to the tanks from which they feed. Therefore, no propellant lines would have to be cut. Also, core booster commonality is still mostly maintained, as the thrust support structure underneath each tank would be identical across all 7 tanks. However, unlike before, the auxilliary engines would not be bolted to the thrust support strucutre, but rather only press against; thus allowing the engines to simply fall away with the stage.

This rocket is far too big for any practical usage we might need in next 50 years.

But still.

At least boosters should use dense fuels, not LH. With the same tank volume, you'll get twice as much dV.

Don't bother with cross-feed, it adds complexity+cost. Just put more engines on the strapons so that they consume fuel faster than core stage.

Pressurized air assist is impractical for this large vehicle. For smaller ones, just use mortar launch instead.

Hmm, I think you have misunderstood.

There is no cross-feed on this rocket, at least not in the traditional sense; i.e. there is no propellent sharing between tanks. Instead, you have some engines under core stages which are actually fed from the outer tanks. This is just another way of putting more engines on the outer stages (which you rightly cite as necessary), but without having the engines take up too much width at the bottom of the tank (which can be a problem with LH2 / LOX powered rockets because of the engines lower thrust, again as you cite).

Also, the compressed air is not used in any way to assist the launch of the rocket. It is simply used to raise the weight of the (un-fueled) rocket off of the ground in preparation for launch (when the columns turn and lock to support the weight of the *fueled* rocket). In other words, it is simply a giant pneumatic jack.

BTW, welcome to the forums. Thanks for contributing!

- Mike

I found a picture of someone's vision of a 1000 ton launch system that is very similar in size to yours. I see a great potential for a LV this big. If there were just a way to get the funding needed for things like this, we could have a colony started on MARS within a hundred years. This could easily be the answer to interplanetary travel within the solar system.

Why not just use Sea Dragon?

Sea Dragon, Sea Dragon, A resurrected Saturn V, are all equally possible. Also equally expensive. All of these concepts have either never been or were discontinued. To rebuild the infrastructure is very close to starting from scratch. It could be done, and I would like it to be done, but somebody's got to pay for it, and I don't have $1/4 trillion dollars lying around!