7.3.2 Pulse Operation
Exhibit B
Accurate
A minimum number of pulses shall be employed per maneuver.
performance for each pulse, including the
predictability of the
thruster
warmup period, shall be provided.
-
1) Size The minimum impulse bit available at maximum inlet pressure from axial thrusters shall cause a satellite spin axis change not attitude control deadband and from to exceed one-fifth of the radial or offset thrusters an orbital velocity change not to exceed 0.02 fps for hot thruster operation.
2) Impulse Bit Repeatability, Individual Thruster - Starting the first with the thruster at orbital nonfiring pulse of a sequence equilibrium conditions, the total impulse produced by the thruster shall be predictable within ±10 percent by any pulse train required to perform one nominal attitude correction or longitude correction while on station.
3)
4)
Starting the first Centroid Repeatability, Individual Thruster
with the thruster at orbital nonfiring pulse of a sequence equilibrium conditions, the maximum pulse centroid variation shall be such that the thrust vector sum of any pulse train required to perform the maneuvers per item 2 shall be predictable within ±10° of spacecraft rotation.
and
-
over
of the
Data Required Prior to and/or during testing, the thruster response influence factors shall be or have been determined for thruster temperature, propellant
propellant temperature,
temperature, propellant inlet valve voltage
the operating range pressure, thruster. Additionally, each thruster shall be accompanied by acceptance test documentation sufficient to demonstrate the above requirements have been met and define the actual characteristics of the thruster. Note, however, that existing radial thrusters will
not be retested.
7.4 Propellant Load
shall be sufficient to orient the maneuver it to either the 105.50 E or attitude and maintain that station and
The propellant tank capacity shall
2)
The minimum propellant leading satellite to the proper attitude, 1160 E longitude orbital location, for
at least 9 year mission life.
a
be 327 lbs.
7.5
Telemetry
The following information shall be included in the telemetry:
1)
Fuel pressure (each system)
2) Fuel tank temperature
3) Thruster valve temperature
.B-26