Acapello

Acapello on the launchpad

The Acapello is a stock vessel that comes with the Making History expansion. It is a Kerbal analogue for the Saturn V, with the first two stages (S-IC and S-II) merged together. It is the heaviest and most expensive stock craft in the game and has the highest part count of any stock craft.

The CSM and Lander Modules Docked in Low Mun Orbit

Craft Description

“

This titanic rocket can propel its paired lander/command module combo to the Mun or Minmus with ease. Make sure to dock the lander and command module together after you decouple them. — Squad

”

Features

It uses a cluster of five Kerbodyne KE-1 "Mastodon" Liquid Fuel Engines for its first stage, like the Saturn V's five F-1s. Its (S-IVB) like-stage uses a Skiff engine. It has a crew capacity of 3 and is capable of landing 2 Kerbals on the Mun or Minmus.

The first stage is considerably overfuelled and is capable of taking the rocket all the way into orbit, making the Acapello an (inefficient) SSTO. In fact, the first stage has so much fuel that it can then place the upper stage and crew modules onto a munar transfer trajectory before running out.

The second stage thus only needs to be used for decelerating the craft into orbit at its target moon, a task for which it too is vastly overfuelled. It also lacks RCS thrusters, making control sloppy when its engine isn't running. If desired, it can be left attached to the munar lander during the latter's descent to the surface to save on the fuel in the lander and allow it to make multiple landings in different locations, but this is tricky due to the aforementioned lack of RCS and the stage's relatively-large mass; it is recommended to only do this if aiming for a landing on flat terrain, as the stage's lack of landing legs makes it tippy otherwise.

Unlike the real Apollo spacecraft, where only the lunar module could descend to the surface and return, the Acapello's CSM is also capable of landing on the Mun and returning with plenty of delta-V to spare, although with its lack of landing legs this can be perilous if not on flat terrain.

Possible improvements

• Add RCS thrusters to the lower portion of the upper stage to make attitude control easier when not thrusting with the engine.
• Reduce the size of the upper stage, since it has far more fuel than it actually needs and the extra mass makes control more difficult.
• Shrink the size of the lower stage, so it's less-dramatically-overfuelled, and split it in two, with a more-efficient vacuum engine or engine array for the new second stage. This eliminates the need to drag the entire first stage into orbit or near-orbit and allows the use of an engine or engines with better vacuum efficiency for the final portion of ascent and orbital insertion.
• Add a Small Inline Reaction Wheel and Z-200 Rechargeable Battery Bank between the M.E.M. and its attached docking port to make it easier to control the lander when its engine isn't operating. One could also stack on a Probodobodyne OKTO2 to allow it to be controlled and deorbited when uncrewed.
• Put landing legs on the CSM to allow it to be more easily landed on rough or sloping terrain and thus allow the two spacecraft to more easily explore the Mun or Minmus independently.

Trivia

• The CSM's SM-25 Service Module has its own built-in liquid-fuel and oxidizer tankage in addition to the numerous separate fuel tanks loaded into it; the version of the SM-25 available from the VAB/SPH parts menu has no internal tankage.
• Unlike the real-life Apollo LM, which had separate descent and ascent stages (leaving the former on the surface of the moon), the Acapello's munar lander is a single-stage craft that deorbits, lands, and reorbits the entire lander.