Proton LV clone...

[Jestersage]

Since I have success with my ESA Hermes, I decide to use it to make the LKS, aka "Soviet mini shuttle". It is suppose to be launch by Proton, which is famous for delivering Salyut, Mir parts, and quite a lot of Commercial cargos to space.

Problem is that while the Shuttle is easily made and launched on that Ariane V clone, trying to make a Proton seems impossible without going with Vector engines.

The first stage is pretty much 6 "side" tanks, each with an engine, radial attached and autostruct to the central tank. So far I have tried making one with 1.25m parts, 2.5m parts; a mix of them; Gave up on 1.25m parts (and thus no more T-30) and gone using Mainsail or Skipper; Removing all fuels from the center "tank"... It refuse to reach orbit. And this thing is suppose to be able to launch the Salyut and Mir!

Did the Russkies discovered some secret sauce that made it so powerful? Must I go with Vector engine? The idea is that I can use something that is cheaper or having lower tech requirement than the Kerbodyne parts...

[Reactordrone]

If you're making a full sized Proton, the mainsail engine has basically the same specs as the RD-253 first stage engine. Second stage engines are more of a problem and the Vector is about as close as you'll get, you just have to knock their thrust down a little.

[Jestersage]

50 minutes ago, Reactordrone said:

If you're making a full sized Proton, the mainsail engine has basically the same specs as the RD-253 first stage engine. Second stage engines are more of a problem and the Vector is about as close as you'll get, you just have to knock their thrust down a little.

Mainsail equal to 1 first stage engine or all 6 of them combined?

[Reactordrone]

2 hours ago, Jestersage said:

Mainsail equal to 1 first stage engine or all 6 of them combined?

One of them. Delta-v to get into Earth orbit is much higher than Kerbin orbit. On the bright side a full sized Proton will get a lot of mass into Kerbin orbit.