Minimum parts Mars mission!

[Marmilo]

Objective: Land on Mars with smallest amount of parts
Criteria: Lowest part count wins, if there's a tie then it's decided by mass
Rules:
-no BP editing
-no cheats
-fully stock (Anaís and closest approach line allowed)
-no exploits
Reward: The winner gets the blueprint to my new Puffin Shuttle.

As always, my submission goes first:

Ugly, innit?

Obviously I don't launch at full throttle with that TWR

Stage separates by being burnt off by engine

55% in LEO

26% on Mars surface

15% in low Mars orbit. I was scared I won't make it at this point.

When I saw I had 1.9% left for my propulsive landing on earth, I breathed a sigh of relief. I knew I can land burning 2% when I have 4%, so having almost 2% was surely enough

What a safe margin!

Achievement screen

Spoiler: Previous designs

Yes, this is the fourth iteration

 

[Sportgus]

Ah I was actually going to try this for a revision of my team frontier mission, lowest mass or part count. Maybe I'll try this

 

[Catalyst_Kh]

This one is very nice!

 

[Marmilo]

New version, reduced part count furthermore.

Altaïr is there a simple way to calculate GA gains?

 

[Catalyst_Kh]

Old version had 6 parts, new version have 6 parts, why it is counted as reduced?

 

[Catalyst_Kh]

Altaïr is there a simple way to calculate GA gains?

I remember i saw some old topic, where they discussed a way how to calculate it. Simplified version - the difference between vectors of approach and going away from celestial body with addition of speeds will be direct answer to how much exactly you gained or lost. So simple angles of vectors and speed values are the arguments of delta V function.

 

[Catalyst_Kh]

There is one trick that can help you and i never heard anyone using it.

For example, you can use 2-3 GA from moon in a row, but you still need to burn fuel at periapsis near moon on the last GA, to gain Mars. That would be fuel burned with less efficiency, than near Earth, and almost negates all benefits from those 2-3 GA.

There is a way do make GA from moon, which will put you directly back to high eccentricity obrit around Earth, where your periapsis will be again near atmosphere, but your apoapsis will be higher than moon. In this way you gain a little extra speed purely for free, because then you still can make Oberth burn from Earth instead of moon and go to Mars from Earth directly.

But i never tested how much delta V you will gain in this way. But it will be something, more than zero, and that is totally for free, since you don't need to burn fuel near the moon at all. Thus it might make a difference in your case. Since you are fighting for each pint of fuel.

For using this option you need to take counterclockwise orbit after launch from Earth. Then GA from Moon will switch your orbit to clockwise instead of throwing your periapsis far away from Earth, as would be in normal case. "Wrong" orbit direction kind of protects you from losing your good Oberth periapsis. But while periapsis will be thrown back with simply switching orbit direction - apoapsis will be thrown higher somewhat nevertheless, which meens you are getting some free delta V.

And you need to approach moon from above for it, not from below, since that allows you to collect more free acceleration from moon before your periapsis will be thrown away from Earth. You can practice all of it in that trainer challenge: link

 

[Altaïr]

@Altaïr is there a simple way to calculate GA gains?

Simple, no. Unless you try yourself with and without GA then check the difference, but I suppose it's not what you meant by "calculate".

If you're not afraid by maths, you can have a good estimation by calculation, but it requires calculating the transfers yourself, then the speed at which you encounter a planet to calculate the deflexion angle and deduce your new velocity vector, but it's painful. Or I should rather say, it was painful when all planet orbits were circular. Now with elliptical orbits the maths become ugly if you want to do it by hand. And it's still an approximation.

In the end the only way to get an accurate answer would be to run a simulation. And guess how you can run a simulation?

 

[Marmilo]

Old version had 6 parts, new version have 6 parts, why it is counted as reduced?

Less mass

There is one trick that can help you and i never heard anyone using it.



For example, you can use 2-3 GA from moon in a row, but you still need to burn fuel at periapsis near moon on the last GA, to gain Mars. That would be fuel burned with less efficiency, than near Earth, and almost negates all benefits from those 2-3 GA.



There is a way do make GA from moon, which will put you directly back to high eccentricity obrit around Earth, where your periapsis will be again near atmosphere, but your apoapsis will be higher than moon. In this way you gain a little extra speed purely for free, because then you still can make Oberth burn from Earth instead of moon and go to Mars from Earth directly.



But i never tested how much delta V you will gain in this way. But it will be something, more than zero, and that is totally for free, since you don't need to burn fuel near the moon at all. Thus it might make a difference in your case. Since you are fighting for each pint of fuel.



For using this option you need to take counterclockwise orbit after launch from Earth. Then GA from Moon will switch your orbit to clockwise instead of throwing your periapsis far away from Earth, as would be in normal case. "Wrong" orbit direction kind of protects you from losing your good Oberth periapsis. But while periapsis will be thrown back with simply switching orbit direction - apoapsis will be thrown higher somewhat nevertheless, which meens you are getting some free delta V.



And you need to approach moon from above for it, not from below, since that allows you to collect more free acceleration from moon before your periapsis will be thrown away from Earth. You can practice all of it in that trainer challenge: link

Simple, no. Unless you try yourself with and without GA then check the difference, but I suppose it's not what you meant by "calculate".



If you're not afraid by maths, you can have a good estimation by calculation, but it requires calculating the transfers yourself, then the speed at which you encounter a planet to calculate the deflexion angle and deduce your new velocity vector, but it's painful. Or I should rather say, it was painful when all planet orbits were circular. Now with elliptical orbits the maths become ugly if you want to do it by hand. And it's still an approximation.



In the end the only way to get an accurate answer would be to run a simulation. And guess how you can run a simulation?

Thanks guys, I'll see what I can do

 

[yonkee]

gg that’s impressive

 

[Marmilo]

I could reduce part count to 5 using the Mercury redstone pack capsule, but that feels cheaty

 

[Catalyst_Kh]

It would look nice:

You never set in your rules that dlc is excluded.

 

[Mars Pathfinder]

It would look nice:

View attachment 101722

You never set in your rules that dlc is excluded.

Is the old capsule with HS on it still on SFS/Example rocket? maybe that could help too as substitute to that?