ARES Program

Mars Colony Mission
34 Design Documents
Created by Erik Bethke using QuestMaster + Claude Opus 4.5

Mars Crew Descent Vehicle Design Document

ARES-LANDER (Atmospheric Re-Entry & Surface) Class

2,286 words
~12 min read
Contains SVG Diagrams
Contains Technical Diagrams
1 AI Thinking Trace

# Mars Crew Descent Vehicle Design Document

ARES-LANDER (Atmospheric Re-Entry & Surface) Class

10-Crew Capacity | Precision Landing | Convertible Surface Habitat

📋 Executive Summary

ParameterSpecification
**Designation**MDV-10 "ARES-LANDER" (Mars Descent Vehicle)
**Crew Capacity**10 nominal / 12 emergency
**Entry Mass**48,500 kg (wet)
**Landed Mass**32,200 kg (dry + crew + cargo)
**Cargo Capacity**5,000 kg crew equipment + personal
**Entry Velocity**5.8 km/s (from Mars orbit)
**Landing Accuracy**≤100 m from target (99% probability)
**Descent Duration**7-9 minutes (entry interface to touchdown)
**Surface Endurance**30 days standalone / indefinite with base
**Propulsion**Hypergolic (MMH/NTO) + throttleable RL-Mars engines
**Landing System**6-leg with terrain adaptive suspension
**Fleet Requirement**5 vehicles (4 crew + 1 cargo variant)

1. Mission Requirements & Constraints

1.1 Design Reference Mission Profile

DESCENT MISSION TIMELINE
══════════════════════════════════════════════════════════════════════════════════

T-24:00:00  Crew transfer from MTV to MDV in Mars orbit
T-12:00:00  Systems checkout, suit donning, pre-descent briefing
T-02:00:00  MDV undocking from MTV
T-01:30:00  Separation maneuver, deorbit burn preparation
T-00:10:00  Deorbit ignition (ΔV = 50 m/s)
T-00:00:00  ENTRY INTERFACE (125 km altitude)
            ════════════════════════════════════════════════
T+00:01:30  Peak heating (48 W/cm², 1,650°C surface)
T+00:03:00  Peak deceleration (4.2g, ~35 km altitude)
T+00:04:00  Supersonic parachute deployment (Mach 2.2, 12 km)
T+00:04:30  Heat shield jettison
T+00:05:15  Subsonic parachute deployment (Mach 0.8, 7 km)
T+00:06:30  Parachute release, powered descent initiation (2 km)
T+00:07:00  Terrain-relative navigation lock
T+00:07:45  Terminal descent phase (100 m)
T+00:08:00  TOUCHDOWN
            ════════════════════════════════════════════════
T+00:15:00  Post-landing safing, crew status check
T+01:00:00  Crew egress (if immediate EVA required)
T+04:00:00  Habitat mode activation

══════════════════════════════════════════════════════════════════════════════════

1.2 Key Design Drivers

RequirementSpecificationDesign Impact
**Crew Safety**Loss of crew probability <1:500Triple redundancy on critical systems
**Entry Corridor**±0.5° flight path anglePrecision guidance, lifting entry
**G-Loading**<5g nominal, <8g abortStructural margins, crew restraints
**Landing Site**Jezero/Syrtis region (18°N)EDL performance at altitude
**Precision**Land within 100m of beaconTRN + hazard avoidance
**Abort Capability**Powered abort through T+5:00Propellant reserves, guidance
**Dust Environment**Operations in 15 m/s windsEngine gimbal authority, leg stroke

1.3 Entry Corridor Analysis

MARS ENTRY CORRIDOR CONSTRAINTS
═══════════════════════════════════════════════════════════════════════════════

Entry Flight Path Angle (γ) at 125 km:

    OVERSHOOT                                              UNDERSHOOT
    (skip out)              NOMINAL CORRIDOR               (excessive g-load)
        │                                                        │
        │    γ = -10°              γ = -14°              γ = -18°│
        │        │                     │                     │   │
        ▼        ▼                     ▼                     ▼   ▼
    ────┬────────┬─────────────────────┬─────────────────────┬───┬────
        │        │                     │                     │   │
        │        │◄──── SAFE ZONE ────►│◄─── ACCEPTABLE ────►│   │
        │        │      (±0.5°)        │       (±1°)         │   │
        │        │                     │                     │   │
        │   Decel: 3.5g           Decel: 4.2g          Decel: 6.5g
        │   Heat: 38 W/cm²        Heat: 48 W/cm²       Heat: 72 W/cm²
        │   Range: Long           Range: Nominal        Range: Short

    ARES-LANDER CAPABILITY:
    ├── Entry corridor width: 1.0° (nominal), 1.8° (max)  
    ├── Guidance: Predictor-corrector with bank angle modulation
    ├── L/D ratio: 0.24 (sufficient for precision landing)
    ├── Bank reversals: 2-4 during entry
    └── Cross-range capability: ±25 km

═══════════════════════════════════════════════════════════════════════════════

2. Vehicle Architecture

2.1 Overall Configuration

ARES-LANDER MDV-10 Mars Descent Vehicle | 10 Crew | Precision Landing System ENTRY CONFIGURATION Backshell (composites) Crew Module PICA-X Heat Shield RCS Pods (4×) 8.5 m diameter LANDED CONFIGURATION Crew Deck (10) Systems Deck Crew Hatch Egress Ramp Main Engines (6×) Landing Pad (6×) 7.2 m height 12.0 m leg span CREW DECK LAYOUT (TOP VIEW) P1 P2 P3 P4 P5 P6 P7 P8 P9 P10 CDR PLT DOCK EGRESS EVA SUITS EMERGENCY CREW POSITIONS Flight Crew (2) Mission Spec. (8) Docking Port Egress Hatch MASS BUDGET Entry Mass (wet): 48,500 kg Structure/Mechanisms: 8,200 kg Heat Shield (PICA-X): 3,800 kg Propulsion (dry): 4,500 kg Propellant: 12,300 kg Crew + Suits: 1,500 kg Cargo + Equipment: 5,000 kg

2.2 Module Breakdown Structure

ARES-LANDER MDV-10 - MODULE BREAKDOWN
══════════════════════════════════════════════════════════════════════════════════

MDV-10 ARES-LANDER
│
├── AEROSHELL ASSEMBLY (Jettisoned T+4:30)
│   ├── Backshell Structure
│   │   ├── Composite shell (carbon-phenolic)
│   │   ├── SIRCA thermal tiles (interior)
│   │   ├── Parachute mortar housings (×3)
│   │   └── Separation pyrotechnics
│   │
│   ├── Heat Shield Assembly
│   │   ├── PICA-X ablative tiles
│   │   ├── SLA-561V carrier structure
│   │   ├── Bond layer / TPS carrier
│   │   └── Separation mechanism
│   │
│   └── Entry RCS System
│       ├── Hydrazine thrusters (8×)
│       ├── Propellant tanks (×4)
│       └── Attitude control electronics
│
├── PARACHUTE SYSTEM (Released T+6:30)
│   ├── Supersonic Drogue (DGB type)
│   │   ├── Diameter: 25 m
│   │   ├── Deployment: Mach 2.2
│   │   └── Material: Kevlar/Nylon
│   │
│   └── Main Parachutes (×3 ringsail)
│       ├── Diameter: 55 m each
│       ├── Deployment: Mach 0.8
│       └── Material: Vectran
│
├── DESCENT MODULE (Lands on surface)
│   ├── Crew Pressure Vessel
│   │   ├── Upper deck (crew stations)
│   │   ├── Lower deck (systems/storage)
│   │   ├── Windows (×6)
│   │   └── Docking adapter (top)
│   │
│   ├── Propulsion System
│   │   ├── Main engines: 6× RL-Mars (throttleable)
│   │   ├── RCS thrusters: 24× 500N
│   │   ├── Propellant: MMH/NTO
│   │   └── Tank capacity: 12,300 kg
│   │
│   ├── Landing System
│   │   ├── Primary legs (×6)
│   │   ├── Crushable honeycomb
│   │   ├── Terrain adaptive joints
│   │   └── Landing pads (0.5 m diameter)
│   │
│   └── Avionics & GNC
│       ├── Flight computers (×3)
│       ├── TRN cameras (×2)
│       ├── LIDAR altimeter
│       ├── Hazard detection system
│       └── Communications array

══════════════════════════════════════════════════════════════════════════════════

2.3 Mass Budget Breakdown

SystemMass (kg)% of Entry Mass
**Aeroshell Assembly**
- Backshell structure2,4004.9%
- Heat shield (PICA-X)3,8007.8%
- Entry RCS8501.8%
- Parachute system1,2002.5%
**Subtotal Jettisoned****8,250****17.0%**
**Descent Module (Dry)**
- Primary structure5,20010.7%
- Landing gear1,8003.7%
- Propulsion (dry)2,4004.9%
- Avionics & GNC8501.8%
- Thermal control6001.2%
- Power system7501.5%
- Life support1,2002.5%
- Crew accommodations8001.6%
**Subtotal Module Dry****13,600****28.0%**
**Propellant**12,30025.4%
**RCS Propellant**8501.8%
**Crew (10 + suits)**1,5003.1%
**Cargo & Equipment**5,00010.3%
**Consumables (30 day)**2,5005.2%
**Margin (15%)**4,5009.3%
**TOTAL ENTRY MASS****48,500****100%**
**LANDED MASS****32,200**66.4%

3. Entry, Descent & Landing Sequence

3.1 Complete EDL Timeline

3.2 Entry Phase Details

GUIDED ENTRY - BANK ANGLE MODULATION
═══════════════════════════════════════════════════════════════════════════════

The ARES-LANDER uses a lifting body entry with bank angle steering:

                        LIFT VECTOR
                            ↑
                           ╱│╲
                          ╱ │ ╲         Bank angle (φ) rotates lift vector
                         ╱  │  ╲        around velocity vector
                        ╱   │   ╲
    BANK LEFT ←────────●────┼────●────────► BANK RIGHT
    (φ = -90°)        ╱     │     ╲        (φ = +90°)
                     ╱      │      ╲
                    ▼       │       ▼
               Drag/Lift    │    Drag/Lift
               component    │    component
                           │
                    VELOCITY VECTOR
                     (into page)

GUIDANCE LAW:
├── Predictor-corrector algorithm
├── State: Position, velocity from IMU + star tracker
├── Prediction: 3-DOF trajectory integration
├── Correction: Bank angle command to null range error
├── Update rate: 10 Hz
└── Bank reversal logic: Cross-range deadband

PERFORMANCE:
├── L/D ratio: 0.24 (capsule with offset CG)
├── Ballistic coefficient: 120 kg/m²
├── Cross-range capability: ±25 km
├── Down-range control: ±300 km
└── Landing accuracy contribution: ±5 km (3σ)

═══════════════════════════════════════════════════════════════════════════════

3.3 Thermal Protection System

ComponentMaterialMax TempThicknessMass
**Forebody Heat Shield**PICA-X1,650°C6.8 cm avg3,200 kg
**Shoulder Region**SLA-561V1,400°C4.2 cm350 kg
**Backshell**SIRCA tiles1,200°C2.5 cm250 kg
**Total TPS****3,800 kg**
PICA-X HEAT SHIELD DESIGN
═══════════════════════════════════════════════════════════════════════════════

    ┌──────────────────────────────────────────────────────────────────┐
    │                      PICA-X TILE LAYOUT                          │
    │                        (8.5 m diameter)                          │
    │                                                                  │
    │                           ╭───────╮                              │
    │                      ╭────│  APEX │────╮                         │
    │                 ╭────│    │ 8.2cm │    │────╮                    │
    │            ╭────│    │    ╰───────╯    │    │────╮               │
    │       ╭────│    │    │                 │    │    │────╮          │
    │  ╭────│    │    │    │                 │    │    │    │────╮     │
    │  │ 4.5│ 5.2│ 5.8│ 6.4│      6.8       │ 6.4│ 5.8│ 5.2│ 4.5│     │
    │  │ cm │ cm │ cm │ cm │      cm        │ cm │ cm │ cm │ cm │     │
    │  ╰────│    │    │    │  (stagnation)  │    │    │    │────╯     │
    │       ╰────│    │    │                 │    │    │────╯          │
    │            ╰────│    │                 │    │────╯               │
    │                 ╰────│                 │────╯                    │
    │                      ╰─────────────────╯                         │
    │                         SHOULDER                                 │
    │                                                                  │
    │  Material: Phenolic Impregnated Carbon Ablator (SpaceX variant)  │
    │  Tile size: 0.5m × 0.5m (gap-filled during installation)         │
    │  Total tiles: 227 (hexagonal packing)                            │
    │  Recession rate: 0.3 mm/s at peak heating                        │
    │  Total recession: ~12 mm (safety factor 5×)                      │
    │                                                                  │
    └──────────────────────────────────────────────────────────────────┘

THERMAL PROFILE:
├── Peak heat flux: 48 W/cm² (at stagnation point)
├── Total heat load: 12,500 J/cm²
├── Peak surface temp: 1,650°C
├── Bondline temp limit: 260°C
├── Predicted bondline temp: 180°C (margin: 80°C)
└── Backface temp at jettison: 85°C

═══════════════════════════════════════════════════════════════════════════════

4. Propulsion System

4.1 Engine Specifications

<artifact identifier="propulsion-system" type="image/svg+xml" title="ARES-LANDER Propulsion System Layout">

ARES-LANDER PROPULSION SYSTEM 6× RL-Mars Main Engines + 24× RCS Thrusters | MMH/NTO Hypergolic BOTTOM VIEW - ENGINE ARRANGEMENT E1 E2 E3 E4 E5 E6 CG ±8° gimbal RCS pods (4×) Main Engine (6×) RCS Pod (4×6=24) PROPELLANT SYSTEM SCHEMATIC MMH FUEL 4,200 kg (Tank 1) MMH FUEL 4,200 kg (Tank 2) NTO OX 5,900 kg (Tank 3) NTO OX 5,900 kg (Tank 4) He
AI Thinking Trace

The user is asking me to help with a specific subtask of designing an interplanetary transportation ...

Previous

Mars Transit Vehicle

Next

Orbital Assembly Operations

Created by Erik Bethke in Bike4Mind using the QuestMaster deep agentic flow + Claude Opus 4.5 by Anthropic