A Case Study in NASA-DoD - The Black Vault

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Appendix G
THERMAL CONTROL SUBSYSTEM: A COMPARISON OF
AEM, STPSS, AND MMS
by
W. D. Gosch
COMPARATIVE EVALUATION OF THE THERMAL CONTROL SUBSYSTEM ON
THE STPSS AND AEM SPACECRAFT
There are two major differences between the thermal control subsystem
of the STPSS and that of the AEM (Table G-l). First, the AEM
design uses louvers, while the STPSS relies on radiators and heaters
for controlling spacecraft component and structure temperatures.
Second, the STPSS requires high temperature insulation around the
Table G-1
THERMAL CONTROL ELEMENTS OF THE AEM, STPSS, AND MMS SPACECRAFT
Spacecraft
AEM STPSS MMS
3-Axis
3-Axis
Element Type I Type 11 Spin Low-Cost Precision 3-Axis
Spacecraft weight (lb) 214 274 888 1043 1167 1312
Thermal control weight (Ib) - 3 3+ a (b) (b) (b) 39
Thermal control elements:
• Louvers 1 2 .. .... 6
* Radiators X X X X X X
* Heaters X X X X X X
* Multilayer insulation X X X X X X
" Thermal coatings X X X X X X
* High-temp. insulation X X X
* Interface insulators X X K X X X
aA second louver and radiator are added for this mission.
bstructure and thermal control weights combined: core middle - 250 lb, spin
module - 75 lb, orientation (low-cost and precision) - 160 lb. TRW did not determine
actual weights of the thermal control elements but they indicate it would
be on the order of 10-15 lb.