Lunar Lander Vehicle Design Overview

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Lunar Lander Vehicle Design Overview
Wayne Lee Lunar Lander Industry Day 13 December
2007
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Vehicle Architecture
Airlock

• Three Primary Elements
• Descent module
• Provides propulsion for LOI and powered descent
• Provides power during lunar transit, descent, and
  surface operations
• Serves as platform for lunar landing and liftoff
  of ascent module
• Ascent module
• Provides propulsion for ascent from lunar surface
  after surface mission
• Provides habitable volume for four during
  descent, surface, and ascent operations
• Contains cockpit and majority of avionics
• Airlock
• Accommodates two astronauts per ingress/egress
  cycle
• Connected to ascent module via short tunnel
• Remains with descent module on lunar surface
  after ascent module liftoff

Ascent Module
Descent Module
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Key Preliminary Specifications

• Number of Crew up to 4
• Sortie Mission Duration 14 days LEO
  (unoccupied)
• 4 days trans-lunar coast
• 1 day LLO
• 7 days surface
• 7 hours ascent (including disposal)
• Total Mass at Lift-off 45,000 to 53,600 kg
• Total Propellant Mass 26,652 kg (sortie)
• Height of Vehicle Stack 10.52 m, legs uncrushed
• Height of DM Deck Above Surface 6.97 m, legs
  uncrushed
• Maximum Diameter of Vehicle 7.5 m, legs stowed
• Diameter of Landed Footprint 14.53 m, legs
  deployed
• Descent Propulsion LOX/LH2 Main, MMH/NTO RCS
• Ascent Propulsion MMH/NTO Main and RCS
• Total ?V Capability 2960 m/s

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Configuration Variants

• Vehicle will be configurable as three different
  variants
• Sortie variant
• Utilized for surface missions up to seven days
  where crew will use ascent module as living
  quarters and a base of operations for EVAs
• Employs all major elements -- descent module,
  ascent module, airlock
• Outpost variant
• Utilized for surface missions up to 210 days
  where crew will work out of a lunar base
• Configured similar to sortie variant, but without
  airlock crew will depressurize ascent module
  upon landing and head directly for outpost
• Keep-alive power assumed to be provided by
  outpost
• Cargo variant
• Utilized to deliver large, presumably outpost
  modules to the surface
• No ascent module or crew cargo will sit on upper
  deck of descent module
• Vehicle components normally resident in ascent
  module will be attached to upper deck of descent
  module

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Configuration Variants
Outpost Variant 45,000 kg Descent Module Ascent
Module
Sortie Variant 45,000 kg Descent Module Ascent
Module Airlock
Cargo Variant 53,600 kg Descent Module Cargo on
Upper Deck
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Configuration Commonality

• Design paradigm is to maximize commonality across
  variants
• Descent module structure optimized to deliver
  maximum amount of payload mounted to the deck in
  cargo mode, but use same structure for all three
• Descent propulsion is identical for all three
  with exception of propellant load
• Launch mass allocation of 45,000 kg for sortie
  and outpost variants increased to 53,600 kg for
  cargo mission due to benefit of Ares V not
  needing to accelerate Orion vehicle through TLI
  burn
• Tanks sized for propellant volume needed for
  53,600 kg cargo mission, but only filled to level
  needed to support sortie and outpost variant mass
• Ascent module structure and propulsion is
  identical for sortie and outpost variants
• Other subsystems are identical in concept for all
  three variants
• Choice of components and sizing are the same for
  all three variants
• Minor variations in schematics and physical
  layout to account for mission-specific details

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Mass Distribution Comparison of Variants
Outpost Mission Lander
Sortie Mission Lander
Uncrewed Cargo Mission Lander

Dry Mass 9,522.1 kg
Non-Propellants and Other 2,568.7 kg
Propellant 26,651.7 kg
Manager's Reserve 2,856.6 kg
Mass Available for Payload 3,400.9 kg
Total Vehicle 45,000 kg
Dry Mass 8,971.9 kg
Non-Propellants and Other 2,287.5 kg
Propellant 26,780.0 kg
Manager's Reserve 2,691.6 kg
Mass Available for Payload 4,269.0 kg
Total Vehicle 45,000 kg
Dry Mass 6,901.2 kg
Non-Propellants and Other 1,351.0 kg
Propellant 26,319.3 kg
Manager's Reserve 2,070.4 kg
Mass Available for Payload 16,958.1 kg
Total Vehicle 53,600 kg
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Structures Summary

• Descent Module Structure
• Cruciform truss configuration, four landing legs
  (stowed at launch)
• Aluminum construction
• Current mass w/o growth 2110 kg
• Ascent Module Structure
• Cylindrical-shaped pressure vessel
• Composite construction
• Current mass w/o growth 625 kg
• Airlock Structure
• Cylindrical-shaped pressure vessel
• Aluminum construction
• Current mass w/o growth 312 kg

Ascent Module
Airlock
Landing Leg
Launch Vehicle Adaptor (EDS)
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Descent Module Configuration
Cruciform Primary Structure
LH2 Tanks (4) LOX Tanks (4)
Upper LH2 Support Struts (32) (tension rods)
Lower LH2 Support Struts (16) (stabilizers)
Lower LOX Tank Support Cones (4)
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Ascent Module Configuration
Docking WindowFrame (2)
LIDS Docking Adaptor (previous version shown)
Front WindowFrame (2)
Top Flange (4)
MMH Tank (2)
Tank Structure (24 struts)
NTO Tank (2)
Lower Interface Beam
Separation System (Marmon Band)
AM/DM Adapter
Engine
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Airlock Configuration
Pressure Shell Skin
EVA Hatch Frame
EVA Hatch Window
AM / Airlock Tunnel Frame
EVA Hatch
AM / Airlock Tunnel
Bottom Flange (4)
Truss Structure Strut (8)
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Propulsion Summary

• Ascent Module Propulsion
• Single MMH/NTO main engine, 24,465 N (5,500 lbf)
  thrust
• 16 MMH/NTO RCS thrusters
• 2 MMH, 2 NTO tanks shared between main and
  thrusters
• Current dry mass w/o growth 666 kg
• Descent Module Propulsion
• Single LOX/LH2 main, 82787 N (18,627 lbf)
  thrust, restart capability, 3.31 throttle ratio
• 4 LOX, 4 LH2 tanks
• 16 MMH/NTO RCS thrusters
• Current dry mass w/o growth 2510 kg

Thrusters (position TBD)
MMH Tank
NTO Tank
Helium Tank
Ascent Main Engine
LH2 Tank
LOX Tank
Descent Main Engine
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DM Main Propulsion Schematic
Pneumatics/Purge
Pneumatic Valve
Pneumatic Vent/Relief Valve
Power System Interface
Relief Valve
Press/Pre-press
Solenoid Valve
Check Valve
GHe Fill/Vent
Pressure Regulator
Filter
Thermodynamic Vent System
TVS
LOX Vent
Diffuser
LH2 Vent
LOX Fill/Drain
LH2 Fill/Drain
LOX-1
LOX-2
LOX-3
LOX-4
TVS
TVS
TVS
TVS
TIVOx1-P
TIVOx2-P
TIVOx3-P
TIVOx4-P
TVCA-1a
TIVOx1
TIVOx2
TIVOx3
TIVOx4
TVCA-1b
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Ascent Propulsion Schematic
tHe1
Function Service Hand Valve, HV High Pressure
Latching Valve, HP Regulator, Rg Check
Valve, CV Filter, F Low Pressure Latching
Valve, LV Solenoid Valve S Burst Disk/ Relief
Valve RV Heater Ht Pressure Sensor
P Temperature Sensor T
Fluids Helium He Nitrogen Tetroxide
(NTO) Ox Monomeythhydrazine (MMH) Fu
tHe2
tHe1
tHe2
HVHe01
pHe1
HPHe1
FHe1
RgHe1
FHe5
FHe6
HVOx1
HVFu01
CVHe2
Thruster 5,6,7,8
CVHe1
LVOx1
Thruster 1,2,3,4
LVFu1
RVFu1
RVOx2
pp1
S
S
S
S
S
S
S
S
pp2
t16
t15
t14
t12
t13
t11
t10
t9
tp5
tp1
tp7
t5
tp3
HVFu4
MMH
MMH
NTO
NTO
HVOx4
t6
tp2
tp6
tp8
tp4
t4
t3
HVFu2
HVOx2
RCS Thruster Quads
LVFu2
LVOx2
FFu1
FOx1
HVOx3
t1
HVOx5
t7
t2
HVFu5
t8
HVFu3
t24
t23
t21
t20
t19
t18
t22
t17
S
S
S
S
S
S
S
S
Ascent Engine
Thruster 13, 14, 15, 16
Thruster 9,10,11,12
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Power Summary

• Descent Module
• PEM fuel cell, 5.5 kW peak production
• Provides AM and DM power for LLO, surface
  operations
• Orion provides 1.5 kW when docked
• Propulsion residuals provide reactants for
  surface operations
• Current inert mass w/o growth 148 kg (sortie)
• Ascent Module and Airlock
• Single primary battery, LiSO2 chemistry, 14.2
  kW-hr capacity
• Current mass w/o growth 139 kg
• Bus
• 28 V unregulated bus

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Thermal Summary

• Ascent Module and Airlock
• Inner loop with coldplates and sublimator
• Heat transferred to outer loop for rejection
  during cruise, LLO, surface
• MLI and black Kapton insulation on structure
• Current inert mass w/o growth 208 kg
• Descent Module
• Outer loop utilizes radiators for heat rejection
• SOFI insulation on propellant tanks, silverized
  teflon and MLI on structure
• Current inert mass w/o growth 974 kg (sortie),
  990 kg (cargo)

Sublimator (attached to AM)
Radiator (another on other side)
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Life Support Summary

• Atmosphere
• Between 57 and 83 kPa
• Cabin loop provides for heat removal
• Suit loop provides for CO2, moisture, heat
  removal from suit umbilicals
• Suit loop also removes CO2 from cabin air via
  amine swing beds
• Water
• Internal tank holds one day of potable water with
  silver ion biocide
• External tank accumulates water from fuel cells
  for internal tank, EVA recharge, and thermal
• Waste
• Collection and disposal provided
• Current mass w/o growth 212 kg (sortie)

Ascent Module Components
Airlock Components
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CDH Design Status

• Project strategy regarding CDH has been not to
  instantiate a baseline design using available
  components
• Over 10 years to go until first flight
• Relatively rapid progress in evolution of
  electronics may render todays design obsolete
• Baseline CDH architecture is currently under
  study by a multi-NASA-center team with the
  following objectives
• Determine functional properties of architectures
  that have favorable characteristics relative to
  Lander performance requirements
• Develop candidate architectural concepts that
  satisfy the desired characteristics, but are
  expandable and extensible
• Identify technology and/or component families
  suitable for use in populating the architecture
• Develop a functional/mass equivalent design
  placeholder using existing parts, if available

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GNC Summary
Lidar and Camera (top front of AM)

• Sensor Suite
• Star tracker and MIMU data for propagation of
  attitude and position for all phases of flight
• Pulsed Doppler radar provides altitude and
  velocity during landing
• Lidar provides range and bearing to Orion during
  rendezvous
• Rendezvous camera used during terminal approach
  prior to docking
• Control Suite
• 16 thrusters on DM allows for attitude control
  during cruise, LLO, descent
• DM main engine gimbals by 6 to keep thrust
  aligned with c.g.
• 16 thrusters on AM allows for attitude control
  and main engine thrust vector pointing during
  ascent

MIMU (inside AM)
Star Tracker
DM RCS Thruster Pod
Radar Electronics (inside DM)
Radar Antennas (not shown, mounted on lower edge
of DM)
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Telecom Summary

• Primary Radio
• S-band transponder for link with Orion and Earth
  
• SSPA with 40 W output power
• 2 ISS-heritage low-gain antennas with 120 field
  of view
• Link Performance
• 80 kbps to 18-m Earth network, 190 kbps to 34-m
  network
• 2.3 Mbps to Orion at 100 km range
• Significant fraction of data volume in minimal
  functional design occupied by overhead (headers,
  IP, etc.)
• EVA Radio
• 802.16 transceiver currently in development

SSPA (top face of AM)
Low-Gain Primary Antennas
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Summary

• Vehicle design shown today is from the first
  design cycle (LDAC-1)
• Minimum functional design not intended for
  flight
• Design basis was the design reference mission as
  opposed to a detailed requirements set
• Implementation choices should not be considered
  frozen with the exception of a few key
  architectural features
• 4 crew, descent propellant, inclusion of an
  airlock, use of LIDS docking adaptor for Orion
• Forward work for FY08
• Evaluate upgrades for safety and reliability
• Evaluate upgrades for lunar global access and
  enhanced functionality
• Mature preliminary design and develop requirement
  sets and specifications
• Evaluate technologies for mass reduction