A Case Study in NASA-DoD - The Black Vault

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solid rocket kick stage motor. This motor is imbedded inside the hexagonal
modules and must be thermally isolated during and after firing
to prevent excessive heat transfer to the spacecraft modules.
The louvers specified for the AEM were flight-qualified on the
Mariner '64 and '71. The Boeing STP 72-1 and the S3 programs used
a total of 17 louver assemblies identical to the ones proposed for the
AEM spacecraft.
Multilayer insulation blankets for shielding the spacecraft from
the heat generated by the solid rocket motors during and after firing
are made of materials that can withstand the higher temperatures, such
titanium.
The "low temperature" multilayer insulation blankets are used to
decouple the spacecraft from the external environment. For the AEM
the blankets consist of an outer layer of aluminized 1 mil Kapton, 10
layers of doubly aluminized 1/8 mil perforated mylar separated by silk
net spacers, a single layer of Dacron plain-woven cloth to act as a
filter, and an inner layer of aluminized 1 mil Teflon (Teflon side
facing the base module). The STPSS uses insulation blankets on the
entire outer surface of each module with the exception of cutouts for
the radiator panels.
On the AEM, heaters are used in the thermal control system solely
for maintaining the orbit adjust system component (thruster valves and
catalyst bed) temperatures within the design limits during the initial
velocity trim. The heaters are subsequently commanded off and remain
inactive for the remainder of the mission. They could be reactivated
at any time by ground command if required. The total heater power required
during velocity trim is 3 W.
The STPSS uses a heater for the solid rocket motor. It is thermostatically
actuated to ensure adequate temperature levels at the time
of firing. The STPSS also uses thermostatically controlled component
heaters with sufficient power to maintain component temperatures above
the minimum allowable under the coldest conditions.
Thermal control coatings used on the AEM and STPSS provide interior
and exterior radiation control. Interior coatings enhance the internal
radiation heat transfer from bay to bay. Coatings are used on the external
surfaces to reduce the temperature effects of direct or reflected