A Reusuable Sea Launched Two Stage? Better Than Spacex?

[Beccab]

Just now, Spacescifi said:

 

If I were trying to sell the idea and I were rich like Elon, the only ones that would want DIY repeat launch ability from the ocean with no infrastructure would be the airforce.

It is simply too OP to jusify civillian use.

But you do need infrastructure. Unless you want to launch ocean water and unfortunate fishes to space/an enemy country, you need to bring there the payload and most likely an upper stage too

[Spacescifi]

6 minutes ago, Beccab said:

But you do need infrastructure. Unless you want to launch ocean water and unfortunate fishes to space/an enemy country, you need to bring there the payload and most likely an upper stage too

 

Read my EDIT please... I think this idea, new one could be a good one.

 

I just think, water is like gold in space, and we have a gold mine, why not use it to get to space easier?

 

Also makes return landings easier.

Edited July 23, 2021 by Spacescifi

[Beccab]

15 minutes ago, Spacescifi said:

 

If I were trying to sell the idea and I were rich like Elon, the only ones that would want DIY repeat launch ability from the ocean with no infrastructure would be the airforce.

It is simply too OP to jusify civillian use.

 

A single booster can launch mulitple second stages suppied by an ocean carrier.

 

Each time it launch, return to the earth and ress...

 

 

That's it!

 

Just make a two stage rocket launched from a carrier in the ocean. First stage lands in ocean.

 

The ocean carrier cracks LH/LOX all day long and has plenty to spare.

Fuels up first stage, attaches another second stage, launch again!

 

That would be faster repeat launches than normal.

 

At least until the carrier runs out of propellant and has to crack more.

This way it is identical to what Starship is planned to do, only that you need some massive ocean carrier with a nuclear reactor on board, are limited by the fuel and the upper stages that can fit on the carrier and have no real benefit from launching from the sea

[Spacescifi]

40 minutes ago, Beccab said:

This way it is identical to what Starship is planned to do, only that you need some massive ocean carrier with a nuclear reactor on board, are limited by the fuel and the upper stages that can fit on the carrier and have no real benefit from launching from the sea

 

Benefits?

 

1. Mobile launch system .

2. Launch anywhere abilty.

 

If a buyer needed that...beyond james bond villains LOL.

[Spica]

There's one big snag with reusable nuclear rockets that I don't seem to see mentioned often enough, especially in discussions of reusable nuclear first stages:
A nuclear reactor that has never fissioned is not going to be radioactive to any worrying extent, but that all changes after it's first turned on.
The more energy it has generated throughout its history, the more radioactive it is. This will make each successive re-use more difficult and dangerous than the last, since a reactor light enough to launch a rocket with will not be heavily shielded. If the reactor is not submerged in the ocean during the recovery process don't expect crews to access the ship without exceeding their legal yearly radiation limits in a matter of seconds.

Here's a diagram of a NTR powered reusable nuclear shuttle concept from the '70s, showing the radiation levels after engine shutdown.
High flight rates are not going to be possible without highly if not fully automated reuse procedures.

[wumpus]

23 hours ago, Spica said:

There's one big snag with reusable nuclear rockets that I don't seem to see mentioned often enough, especially in discussions of reusable nuclear first stages:
A nuclear reactor that has never fissioned is not going to be radioactive to any worrying extent, but that all changes after it's first turned on.
The more energy it has generated throughout its history, the more radioactive it is. This will make each successive re-use more difficult and dangerous than the last, since a reactor light enough to launch a rocket with will not be heavily shielded. If the reactor is not submerged in the ocean during the recovery process don't expect crews to access the ship without exceeding their legal yearly radiation limits in a matter of seconds.

First, put any propellant/fuel between the engine and the crew compartment.  Any other gases, water, whatever as hydrogen isn't going to be all that effective in blocking radiation no matter how many kgs you have.

Second, I've often suggested that simply jettisoning the fuel rods after a single use could easily be the way to go, especially at first.  Mostly so you don't have to cool the reactor by running propellant through it (thus killing Isp), but also so most of your radioactive mass no longer threatens the crew.  I neither have the data, nor have the skills to crunch it for this type of thing to say it would absolutely be better, but suspect it should definitely be on the table when considering a crewed nuclear vessel (possibly even an uncrewed vessel that starts and stops the engine a lot).