There are 2 ApolloX programs addressed in my REPOS:
-
[1] ApolloX (Earth → Moon → Earth) (this REPO)
-
[2] ApolloXM (Earth → Mars → Earth)
Intended audience
- Aerospace enthusiasts
- KSP / RO users
- Systems & architecture engineers
- Readers interested in launch vehicle design tradeoffs
Yes — it can.
ApolloX demonstrates that the Saturn V launch architecture remains viable when implemented with modern propulsion, materials, and avionics.
|
By replacing:
|
By Keeping:
|
/GameData— Kerbal Space Program / Realism Overhaul configuration files/Ships/VAB/Apollo-X— Reference vehicle craft files (v3.2 / v3.3)README.md— Architectural definition and analysisLICENSE— MIT License
The plugin source is provided under source/Plugins.
Compiled binaries are not included and must be built locally.
Download the release archive and extract the GameData folder into your KSP installation.
The plugin source is provided in this repository under source/Plugins.
Compiled binaries are included only in release archives.
ApolloX is a modern vehicle built on a very good architecture inspiration (Saturn V) that never stopped working.
- A good Architecture does not age.
- Technology does — and it ages fast.
ApolloX exists to prove exactly that.
- Apollo Program succeeded because its architecture was correct.
- Saturn V did not age because architecture does not age.
- The technology used to implement it did.
- The Saturn V–derived architecture applies to the launch vehicle only
- Lunar / Martian Modules (LM / MM) are mission-specific spacecraft
- They are intentionally excluded from the launch architecture
- This separation is fundamental to the original Apollo design philosophy
A good architecture scales without redesign.
- We do not need to reinvent the wheel
- We build wheels for cars or for trucks
The same launch architecture supports:
- Different payload masses
- Different mission profiles
- Different destination modules
Without structural redesign.
ApolloX implements a Saturn V–derived architecture using modern propulsion hardware.
- High-performance engines developed for Starship provide the core propulsion
- Architecture, staging logic, and mission decomposition remain Saturn V–derived
Out of 108 total vehicle parts, only four are SpaceX-derived propulsion elements.
The architecture itself remains classical.
v3.2 is based on Raptor engines, is retained as a baseline reference.
v3.3 is based on RS-25 engines, represents the current production architecture.
v3.2 and v3.3 are technology variants of the same architecture, not competing designs.
All performance values are simulator-derived and include ascent margins unless explicitly stated otherwise.
The following payload sweep demonstrates that ApolloX performance scales smoothly with mass, confirming architectural robustness rather than payload-specific optimization:
| Payload (kg) | ApolloX v3.2 Total Δv (m/s) | ApolloX v3.3 Total Δv (m/s) |
|---|---|---|
| 0 | 21222 | 22767 |
| 1000 | 20936 | 22469 |
| 1600 | 20777 | 22303 |
| 2200 | 20626 | 22144 |
| 2800 | 20483 | 21994 |
| 3400 | 20346 | 21850 |
| 4000 | 20216 | 21712 |
| 4600 | 20091 | 21580 |
| 5200 | 19971 | 21453 |
| 5800 | 19856 | 21331 |
| 6400 | 19746 | 21214 |
| 7000 | 19639 | 21100 |
| Oneway - Payload (kg) | Oneway - ApolloX v3.2 Total Δv (m/s) | Oneway - ApolloX v3.3 Total Δv (m/s) |
|---|---|---|
| 7100 | 21222 | 22767 |
| 8100 | 20936 | 22469 |
| 8700 | 20777 | 22303 |
| 9300 | 20626 | 22144 |
| 9900 | 20483 | 21994 |
| 10500 | 20346 | 21850 |
| 11100 | 20216 | 21712 |
| 11700 | 20091 | 21580 |
| 12300 | 19971 | 21453 |
| 12900 | 19856 | 21331 |
| 13500 | 19746 | 21214 |
| 14100 | 19639 | 21100 |
Δv values include full ascent margin and exclude mission-specific payload propulsion.
For consistency and technical clarity, all Saturn V values in the following tables refer specifically to the Apollo 11 mission configuration.
As there was no single fixed “Saturn V” design, each vehicle evolved across the Apollo program through incremental performance, mass, and reliability upgrades.
Using Saturn V – Apollo 11 as the reference provides a historically representative and well-documented baseline for comparison.
Unless otherwise stated, all Saturn V parameters (thrust, mass, ISP, tankage, and staging behavior) should be interpreted as Apollo 11 flight hardware values, not averaged or generalized Saturn V figures.
| Parameter | Saturn V (Saturn S-IC) | ApolloX v3.2/v3.3 (Saturn S-IC Custom) |
|---|---|---|
| Role | Atmospheric lift | Atmospheric lift |
| Engines | 5 × F-1 | 1 × Super Heavy–class cluster |
| Propellant | RP-1 / LOX | LCH₄ / LOX |
| Total Thrust (ATM) | ~34 MN | ~65.7 MN |
| Total Thrust (Vac) | ~38 MN | ~71.3 MN |
| Isp (ATM) | ~263 s | ~364 s |
| Isp (Vac) | ~304 s | ~395 s |
| Engine Mass | ~42.2 t (5 × F-1) | 20.3 t (cluster) |
| Tank Wet Mass | ~2,300 t | ~3,590 t |
| Architecture | Thrust-first | Thrust-first |
| Reusability | No | Engine hardware reusable |
- Saturn V achieved ~34 MN using five extremely large engines.
- ApolloX achieves ~71 MN using a single clustered engine system, enabled by:
- higher chamber pressures
- methalox efficiency
- modern turbomachinery
- The thrust increase is intentional and compensates for:
- heavier upper stages
- higher total vehicle mass
- modern safety margins
This is architectural continuity, not replication: the role, staging logic, and thrust-first philosophy are preserved, while the technology is modernized.
| Parameter | Saturn V (S-II, Apollo 11) | ApolloX v3.2 (S-II Custom) | ApolloX v3.3 (S-II Custom) |
|---|---|---|---|
| Role | High-altitude acceleration | High-altitude acceleration | High-altitude acceleration |
| Engines | 5 × J-2 | 1 × Raptor cluster | 3 × RS-25 |
| Propellant | LH₂ / LOX | LCH₄ / LOX | RP-1 / LOX |
| Total Thrust (Vac) | ~5.1 MN | ~9.4 MN | ~6.8 MN |
| Isp (Vac) | ~421 s | ~377 s | ~452 s |
| Engine Mass | ~9 t | ~3.5 t | ~10.2 t |
| Tank Wet Mass | ~456 t | ~299 t | ~300 t |
| Tank Pressurization | Helium | Helium | Helium |
| Architecture | Vacuum-optimized, thrust-first | Vacuum-optimized, thrust-first | Vacuum-optimized, thrust-first |
| Restart Capability | Limited | Multiple (×12) | Multiple (×12) |
Stage-2 performs:
- Ascent from ~5 km/s to orbital velocity
- Earth orbit insertion
- Orbit circularization
- Initial Trans-Lunar Injection (TLI) when beneficial
Stage-2 is not payload-optimized.
It is architecture-optimized, preserving Saturn V staging logic
while allowing propulsion technology to evolve.
-
v3.2 (Raptor) emphasizes:
- very high thrust
- low engine mass
- methalox simplicity
-
v3.3 (RS-25) emphasizes:
- maximum vacuum efficiency
- reduced propellant requirements
- tighter Δv margins for heavy payloads
Both preserve the same architectural role: only the propulsion technology changes.
Architecture remains constant.
Technology iterates.
Note:
In ApolloX, Earth orbit insertion and circularization are completed by the final burn of Stage-2.
Stage-3 is therefore a dedicated Translunar Injection stage, responsible for completing the TLI burn.
| Parameter | Saturn V (S-IVB, Apollo 11) | ApolloX v3.2 (S-IVB Custom) | ApolloX v3.3 (S-IVB Custom) |
|---|---|---|---|
| Role | Translunar Injection (TLI) | Translunar Injection (TLI only) | Translunar Injection (TLI only) |
| Orbit Insertion | Partial (S-II → S-IVB overlap) | Completed by Stage-2 | Completed by Stage-2 |
| Engines | 1 × J-2 | 1 × Raptor SL | 1 × RS-25 (throttled) |
| Propellant | LH₂ / LOX | LCH₄ / LOX | LH₂ / LOX |
| Thrust (Vac) | ~1.0 MN | ~1.1 MN | ~2.28 MN (throttled) |
| Isp (Vac) | ~421 s | ~377 s | ~452 s |
| Engine Mass | ~1.8 t | ~2.4 t | ~3.4 t |
| Tank Wet Mass | ~119 t | ~70 t | ~71 t |
| Ignitions | 1 (TLI) | Multiple (restartable margin) | Multiple (restartable margin) |
| Architecture | Dedicated TLI stage | Dedicated TLI stage | Dedicated TLI stage |
- Mission role is preserved across all vehicles:
- a clean, single-purpose TLI stage
- Responsibility boundary evolves:
- Apollo: orbit insertion shared between S-II and S-IVB
- ApolloX: orbit insertion fully completed before Stage-3
- Technology progression:
- Apollo 11: hydrolox, single-start
- ApolloX v3.2: methalox, restartable
- ApolloX v3.3: hydrolox, very high Isp, restartable
This is an evolution of execution, not a redesign of architecture.
Architecture stays the same.
Responsibilities move upstream.
Propulsion efficiency increases — mission logic does not.
| Parameter | Apollo Service Module (Apollo 11) | ApolloX CPM v3.2 | ApolloX CPM v3.3 |
|---|---|---|---|
| Crew | No | No | No |
| Primary Role | Propulsion + life support | Propulsion + guidance + control | Propulsion + guidance + control |
| Main Engine | AJ10-137 (SPS) | 1 × Raptor (throttled) | 1 × RS-25 (throttled) |
| Propellant | Aerozine-50 / N₂O₄ | LCH₄ / LOX | RP-1 / LOX |
| Thrust (Vac) | ~91 kN | ~1.1 MN | ~1.1–2.3 MN (throttled) |
| Isp (Vac) | ~314 s | ~377 s | ~452 s |
| Engine Mass | ~0.65 t | ~2.4 t | ~3.4 t |
| Tank Wet Mass | ~18.6 t | ~37 t | ~37 t |
| Tank Pressurization | Helium | Helium | Helium |
| Restart Capability | Multiple | Multiple (×12) | Multiple (×12) |
| Reusability | Single mission | Multi-mission capable | Multi-mission capable |
| Architecture | Dedicated service module | Integrated control–propulsion core | Integrated control–propulsion core |
The Control–Propulsion Module (CPM):
Always performs:
- Lunar Orbit Insertion (LOI)
- Lunar orbit circularization
- Trans-Earth Injection (TEI)
• v3.2 CPM may additionally perform the final ~100–200 m/s of TLI
• v3.3 CPM performs no TLI — Stage-3 completes it fully
This mirrors the mandatory role of the Apollo SM, while allowing controlled overlap when architecturally beneficial.
- Apollo SM used a low-thrust, high-reliability hypergolic engine designed for long-duration mission support.
- ApolloX CPM consolidates propulsion, guidance, and control into a single reusable core.
- Version v3.2 prioritizes methalox commonality with launch stages.
- Version v3.3 prioritizes maximum efficiency, adopting RS-25 class performance for:
- Lunar orbit insertion (LOI)
- Trans-Earth injection (TEI)
- Partial TLI support when required
This preserves Apollo mission logic while modernizing propulsion capability.
Apollo 11 LM Descent Stage vs ApolloX DLM v3.2 / v3.3
| Parameter | Apollo LM (Apollo 11 Descent Stage) | ApolloX DLM v3.2 / v3.3 |
|---|---|---|
| Primary Role | Lunar descent, landing, surface support | Lunar descent, landing, surface support |
| Crew | No (crew housed in ascent stage) | No (remotely operated / autonomous) |
| Mission Domain | Lunar surface operations | Lunar surface operations |
| Architecture | Dedicated descent stage | Dedicated descent & landing module |
| Main Engines | 1 × LM Descent Engine (LMDE) | 2 × Agena rocket engines |
| Propellant | Aerozine-50 / N₂O₄ (hypergolic) | UDMH / IRFNA-III (hypergolic) |
| Engine Type | Deep-throttle, restartable | Vacuum-optimized, restartable |
| Thrust (Vac) | ~45 kN (throttleable ~10–100%) | ~90 kN total (2 × Agena) |
| Isp (Vac) | ~311 s | ~323 s |
| Engine Mass | ~0.18 t | ~0.14 t (2 × Agena) |
| Tank Pressurization | Helium | Helium |
| Ignition Capability | Multiple (hypergolic) | Multiple (hypergolic) |
| Throttle Capability | Yes (precision landing & hover) | Yes (deep throttle suitable for landing) |
| Redundancy | Single engine, multiple valves | Multi-engine + distributed tankage |
| Reusability | Single mission | Single mission (v3.2/v3.3 baseline) |
| Design Philosophy | Reliability-first, landing safety | Reliability-first, Apollo-style logic |
| Feature | Apollo LM Descent Stage | ApolloX DLM v3.2 / v3.3 |
|---|---|---|
| Tank Architecture | Multiple distributed tanks | 8 peripheral + 1 central tank |
| Structural Role | Landing legs + load-bearing stage | Structural spine + distributed mass |
| Total Propellant (wet) | ~10.3 t | ~23.7 t (simulator measured) |
| Surface Support | Power, consumables, structure | Propellant + structure only |
- Mission role is identical: controlled lunar descent and safe landing.
- Apollo used one highly throttleable engine; ApolloX uses engine redundancy instead.
- Both rely on hypergolic ignition to eliminate start-up risk.
- ApolloX trades minimum mass for fault tolerance and controllability.
This is not a redesign — it is a redundancy-enhanced implementation of the same landing logic.
| Tank Group | Quantity | Diameter | Length | Wet Mass (per tank) | Role |
|---|---|---|---|---|---|
| Peripheral Tanks | 8 | 1.125 m | 2.000 m | ~2.37 t | Primary descent propellant |
| Central Tank | 1 | 4.500 m | 0.250 m | ~4.75 t | Trim, balance & redundancy |
Total Tank Wet Mass: ~11–12 t (simulator measured)
- The DLM deliberately uses hypergolic propulsion to eliminate ignition risk during:
- Powered descent
- Hover
- Final touchdown
- Distributed tank architecture provides:
- Fault tolerance (no single-point tank failure)
- Improved mass balance throughout descent
- Stable center-of-mass evolution
- The central 4.5 m tank functions as:
- A structural spine
- A propellant trim reservoir
- A redundancy buffer for terminal landing phases
- This configuration is architecturally equivalent to the Apollo LM descent stage, rather than a modern single-tank lander.
Total Tank Wet Mass: 8 x 2.37t + 4.75t = 23.71t (simulator measured)
Note: The DLM is unchanged between ApolloX v3.2 and v3.3.
| Parameter | Apollo LM (Apollo 11 Ascent Stage) | ApolloX ALM v3.2 / v3.3 |
|---|---|---|
| Primary Role | Lunar ascent & rendezvous | Lunar ascent & rendezvous |
| Crew | Yes (2 astronauts) | No (autonomous / remotely guided) |
| Mission Domain | Lunar ascent only | Lunar ascent only |
| Architecture | Dedicated ascent stage | Dedicated ascent module |
| Main Engine | 1 × LM Ascent Engine | 1 × Agena rocket engine |
| Propellant | Aerozine-50 / N₂O₄ | UDMH / IRFNA-III |
| Engine Type | Fixed-thrust, restartable | Vacuum-optimized, restartable |
| Thrust (Vac) | ~16 kN | ~45 kN |
| Isp (Vac) | ~311 s | ~323 s |
| Engine Mass | ~0.08 t | ~0.07 t |
| Propellant Tank | 1 × central tank | 1 × central tank |
| Tank Diameter | ~1.9 m | 1.875 m |
| Tank Length | ~1.3 m | 1.250 m |
| Tank Wet Mass | ~2.4 t | ~4.1 t |
| Tank Pressurization | Helium | Helium |
| Ignition Capability | Multiple (hypergolic) | Multiple (hypergolic) |
| Throttle Capability | No (on/off) | Limited (ascent-optimized) |
| Redundancy | None (single engine, single tank) | None (single engine, single tank) |
| Reusability | Single mission | Single mission |
| Design Philosophy | Minimum mass, crew safety | Minimum mass, minimum complexity |
- Mission logic is identical:
- Lift off from lunar surface
- Achieve lunar orbit
- Rendezvous with command module
- Apollo optimized for crew survival and mass minimization.
- ApolloX removes crew constraints and increases performance margin.
- Both use simple, hypergolic, ignition-safe propulsion.
The ALM is intentionally conservative — because ascent failure is unrecoverable.
Terminology Note:
The terms Habitat and Crew Module are synonymous in ApolloX documentation and refer to the same physical module.
The Habitat Module (HM) — also referred to as the Crew Module — is the only pressurized and crewed volume in the ApolloX mission.
- Pressurized
- Crew lives here for the entire mission
- Never separated from the crew
Astronauts:
- launch in it
- cruise in it
- land on the Moon in it
- return to Earth in it
The Habitat does not perform propulsion, landing, ascent, or orbital maneuvering.
It is treated as payload by all propulsion elements below it:
- ALM propulsion stack
- DLM descent system
The crew survives by architectural separation of concerns, not by embedding propulsion or landing authority inside the Habitat.
The Habitat is not disposable and is the only module that returns to Earth intact.
ApolloX is not:
- a minimum-mass lunar lander
- a crew-on-landing-risk architecture
- a single-use or stunt vehicle
- an ISRU-dependent system
- a surface-operations–optimized design
ApolloX deliberately prioritizes:
- clear separation of concerns
- fault tolerance over mass minimization
- architectural correctness over local optimization
Performance margins are intentional and exist to validate the architecture,
not to extract the last kilogram of payload.
ApolloX is a reference architecture — not the final form of lunar operations.
ApolloX is a modern vehicle built on a very good architecture that never stopped working, but the technology used aged.
What This Repository Contains
- Vehicle architecture definition
- Mass budgets and Δv analysis
- Simulator-derived performance sweeps
- Comparative tables against Apollo 11
What This Repository Does Not Contain
- Manufacturing drawings
- Cost modeling
- Program timelines
- Political or funding assumptions
This prevents misinterpretation without weakening the work.