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3 System Design of Lunar Lander
Table 3.3 Major system specifications of the CE-3 lunar lander
Item
Major specifications
System specifications
Mass
Launch mass less than 3780 kg
Dry mass 1200 kg
Dimension
Diameter 3650 mm, height
3600 mm
Operation time on lunar surface Longer than 12 months
Reliability (End of Life)
≥0.65
Structure and mechanisms Configuration
Truss with panel, landing legs
for cushion
Landing cushion
Condition for not to turn over
Slope less than 8°, height of
hump or depth of pit less than
20 cm, vertical velocity less than
3.8 m/s, horizontal velocity less
than 1 m/s, attitude within ±4°
Angle between axis X of lunar
lander with opposition of local
Moon gravity after stable landing
≤14°
GNC
Requirements for landing site
selection
Height of hump or depth of pit:
< 20 cm
Slope: < 8°
Requirements for landing
velocity
Vertical velocity less than
3.8 m/s
Horizontal velocity less than
1 m/s
Control error of three axis
angular rate
1°/s
Control error of three axis
attitude
1°
Propulsion
Propellant
Bi-propellant: dinitrogen
tetroxide (MON-1),
monomethylhydrazine (MMH)
Engine for orbit control
Throttlable engine: 7500 N,
1500 N–5000 N
Nominal specific: 305 s
Thrusters for attitude control
16×150 N and 12×10 N
Specific of 150 N thruster:
≥290 s
Specific of 10 N thruster: ≥275 s
Thermal control
Operation temperature
−20–55 °C
Storage temperature
−50–70 °C
Output heat power of RHU
≥120 W
TT&C
Frequency
S/X/UHF
Data rate of tele-command
1000 b/s
(continued)