Kerbal Space Program
2,268 Mods
Kerbal Planetary Base Systems
1M DownloadsParts for bases on other planets. Includes Habitats, Greenhouse, support for Life Support mods and much more.
KW Rocketry v2.7
743k DownloadsThe comprehensive launch vehicle construction pack
B9 Aerospace 5.2.8
723k DownloadsEssential and enormous set of structural, control, propulsion, command and utility parts for aerospace designs.
OPT Space Plane Parts V2.0
646k DownloadsLarge, Sleek Spaceplane Parts!
Docking Port Alignment Indicator
640k DownloadsThe Docking Port Alignment Indicator is designed to help you dock manually, by presenting target alignment and relative position in a clean and intuitive manner.
Near Future Spacecraft Parts
620k DownloadsStockalike spacecraft parts with a futuristic look
BDArmoryContinued
409k DownloadsThe Original Weapons Mod by BahamutoD, continued!
Near Future Exploration
266k DownloadsNew probe and communication parts
Mark IV Spaceplane System
242k DownloadsA stockalike spaceplane fuselage capable of lifting 2.5m parts
Firespitter
199k DownloadsPropeller plane and helicopter parts
MechJeb Embedded Universal
195k DownloadsMechJeb Embedded with ModuleManager it Gives MechJeb Functionality to every command module, even from mods! Version Independent (should be :P) Career mode supported
Stockalike Station Parts Expansion
163k DownloadsSpace station and surface base parts [just updated with more parts]
QuizTech Aero Pack
114k DownloadsA pack for stock-a-like and miscellaneous spaceplane parts!
kOS: Scriptable Autopilot System
110k DownloadskOS is a scriptable autopilot Mod for Kerbal Space Program. It allows you write small programs that automate specific tasks. kOS was originally written by Nivekk, In his absence I am continuing it.
Kerbalized SpaceX
109k DownloadsA small parts pack aiming to give players a chance to play with some spaceX inspired vehicles.
Free IVA
97.9k DownloadsMove around the inside of your vessels!
SSTU - Shadow Space Technologies Unlimited
97.7k DownloadsLow Part-Count Solutions and Modular Parts
[1.0.4] SciFi Shipyards (discontinued)
95.9k DownloadsIncludes a variety of fictional ships such as the Enterprise and the TARDIS.
Spaceplane Plus (Obsolete)
89.8k DownloadsThis mod is now included in the Stock game!
SpaceX Launch Pack (LLP) by LazarusLuan
82.5k Downloads35-piece complete parts pack for KSP that includes the SpaceX Dragon V2, Dragon Cargo, Falcon 9 v1.1, Falcon Heavy and SHERPA launch systems.