600t atlas after reentry update

Marmilo

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#1
Disclaimer: I did this quite some time ago, so I might not remember everything correctly



The atlas challenge is one of the 6 team hawk challenges. To complete it you have to launch 600t to Leo in a single buildscreen, without part clipping. It was really easy before the reentry update.

Here's my original Atlas mission
My Hawk Entries Thread

As you see, I had quite a bit of fuel left, and that was first try. (Technically second, but that previous one turned out to be 500t).

The problem

If you look at basically any atlas entry, you will see engines stacked on top of one another (not overlapping, just with the nozzle sitting right on top of a fuel tank).
This is an example of a heavy lift launcher (in the single buildscreen category), iirc this was from my Christmas challenge entry
Screenshot_20211223-172514.jpg

See what I mean with those titans?
You see, a good rocket has somewhere around a 1:4 payload ratio (which means that the payload takes up about 25% of the launcher's mass. So, to launch 600t into Leo you will need a 2400t launcher. This sums up to 3000t of total mass. Now, the optimal launch TWR (Thrust to Weight Ratio) is around 1.2-1.4

Let's assume 1.2 in this case. To achieve this twr in a 3000t rocket, you need 3600t of thrust (3000 * 1.3 = 3600). A single titan engine has 400t thrust. So you will need 9 titans. Here's the problem: The reentry update doesn't let you stack engines vertically, and you can't fit 9 titans in one row in the buildscreen.

The solution:

MY first thought was to remove the sides of the launcher to make room for 2 extra titans (and their plumes). It looked a bit like this:
Screenshot_20220430-124823.png

However, this launcher simply wasn't big enought to get 600t to orbit, so.. I had to take a different approach. I think we can agree that the buildscreen was simply too small to do it with the regular approach. So, I guess the solution is... Get more space! And no I will not be buying the expansion. This is what I came up with:
Screenshot_20220501-095941.png

Now, if you don't look carefully you might say "oh but the titans will destroy a lot of stuff there"
Could you please repeat that?
MovaviClips_Video_20220501-101015 (4).gif

Part 2 coming soon
 
Last edited:

Marmilo

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#3
I was so happy when I finally got this thing to work
 

Marmilo

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#4
Anyhow, Part 2!

Here it's just gonna be me talking about my rocket.

Where did we finish?

Oh yeah. So, I decided to stretch the rocket so that I could fit more Titans. After dealing with problems like getting the fuel in the stages to good proportions, making sure that the extension system was working smoothly and reliably an making sure that no parts get destroyed to to engine pivoting, I was ready to go.

This is how the rocket looks like fully prepared for flight. The solar panels were safely ejected and the extension system is fixed with a docking port.
Screenshot_20220111-103408.jpg


So, now we increased the number of titans available from 6 to 10, and have a TWR of 1.41 (could've added some more fuel here and there tbh), we're now ready for liftoff!
Screenshot_20220111-103918.jpg

Now that I look at this, this could've been a great opportunity to use asparagus staging lol (komodo staging to be specific)

The bottom part of the main stage ran out a bit earlier than the top part, due to a bit if fuel transferring. Anyways, after both were gone we're left with the upper stage, at an altitude of 22km an a velocity of over 700m/s, almost sideways. This means we'll only need around 1000m/s of DeltaV (Altair if you're reading this, please don't hesitate to point out any miscalculations on my part). This stage can easily provide that, although due to the low TWR it is going to take a while.
Screenshot_20220111-104058-1-1.jpg

After a while we reach LEO.
Screenshot_20220111-104226-1.jpg

Still got quite a bit of fuel left, 23% to be exact.
Screenshot_20220111-104232.jpg

The payload is 100% full of course
Screenshot_20220111-104238.jpg


As you see, it is most definitely possible to do the 600t version of the atlas challenge after the engine heating update
 

Altaïr

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#5
Ha, well thought, I didn't think about that.

Personally I made it that way:
Spaceflight Simulator_2022-05-01-19-24-13.jpg
Only a row of Titans for the first stage, and the second stage assists the first one with 6 of its 9 engines. That gives a bit more efficiency, and the Frontier engines have a shorter exhaust.

Then the flight:
Spaceflight Simulator_2022-05-01-19-24-54.jpg Spaceflight Simulator_2022-05-01-19-25-53.jpg Spaceflight Simulator_2022-05-01-19-26-29.jpg Spaceflight Simulator_2022-05-01-19-27-09.jpg Spaceflight Simulator_2022-05-01-19-27-25.jpg Spaceflight Simulator_2022-05-01-19-29-16.jpg

And here are 600 tons in orbit. Plus 18 tons of remaining fuel.

Too bad that I can't get the badge! :p
 

Marmilo

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#6
Your approach was a lot more conventional (in a good way). I somehow failed to think of anything reasonable, instead going for some wacky contraption
 

Altaïr

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#7
Your approach was a lot more conventional (in a good way). I somehow failed to think of anything reasonable, instead going for some wacky contraption
Yours is well thought to be honest.

However, if you like unconventional approaches, here is mine:
Spaceflight Simulator_2022-05-01-23-21-59.jpg

Instead of launching 600 tons to space, I'll launch the launcher that can launch 600 tons to space!

Spaceflight Simulator_2022-05-01-23-22-55.jpg Spaceflight Simulator_2022-05-01-23-24-32.jpg Spaceflight Simulator_2022-05-01-23-25-06.jpg Spaceflight Simulator_2022-05-01-23-26-17.jpg
Orbit!

But why stopping here? I'll honor that beautiful launcher as it deserves:
Spaceflight Simulator_2022-05-01-23-29-49.jpg Spaceflight Simulator_2022-05-01-23-30-38.jpg

Rest in pieces :p
Spaceflight Simulator_2022-05-01-23-31-33.jpg Spaceflight Simulator_2022-05-01-23-31-17.jpg
 

Marmilo

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#8
Lmao I'm dying. Whatever launcher you make, you can count on altair being able to send it to space! Unless your name starts with "H" and ends with "orus" of course
 

Mars Pathfinder

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#9
Disclaimer: I did this quite some time ago, so I might not remember everything correctly



The atlas challenge is one of the 6 team hawk challenges. To complete it you have to launch 600t to Leo in a single buildscreen, without part clipping. It was really easy before the reentry update.

Here's my original Atlas mission
My Hawk Entries Thread

As you see, I had quite a bit of fuel left, and that was first try. (Technically second, but that previous one turned out to be 500t).

The problem

If you look at basically any atlas entry, you will see engines stacked on top of one another (not overlapping, just with the nozzle sitting right on top of a fuel tank).
This is an example of a heavy lift launcher (in the single buildscreen category), iirc this was from my Christmas challenge entry
View attachment 82452
See what I mean with those titans?
You see, a good rocket has somewhere around a 1:4 payload ratio (which means that the payload takes up about 25% of the launcher's mass. So, to launch 600t into Leo you will need a 2400t launcher. This sums up to 3000t of total mass. Now, the optimal launch TWR (Thrust to Weight Ratio) is around 1.2-1.4

Let's assume 1.2 in this case. To achieve this twr in a 3000t rocket, you need 3600t of thrust (3000 * 1.3 = 3600). A single titan engine has 400t thrust. So you will need 9 titans. Here's the problem: The reentry update doesn't let you stack engines vertically, and you can't fit 9 titans in one row in the buildscreen.

The solution:

MY first thought was to remove the sides of the launcher to make room for 2 extra titans (and their plumes). It looked a bit like this:
View attachment 82448
However, this launcher simply wasn't big enought to get 600t to orbit, so.. I had to take a different approach. I think we can agree that the buildscreen was simply too small to do it with the regular approach. So, I guess the solution is... Get more space! And no I will not be buying the expansion. This is what I came up with:
View attachment 82449
Now, if you don't look carefully you might say "oh but the titans will destroy a lot of stuff there"
Could you please repeat that?
View attachment 82450
Part 2 coming soon
Sneaky boi (☞ ͡° ͜ʖ ͡°)☞
 

Altaïr

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#10
Lmao I'm dying. Whatever launcher you make, you can count on altair being able to send it to space! Unless your name starts with "H" and ends with "orus" of course
No chance that I can launch a Komodo indeed. For all the rest, you can trust me to launch it to space :p