[meteorite-list] Supplementary Orbit Raising Manoeuvre Planned for Mars Orbiter Spacecraft (MOM)
From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Mon, 11 Nov 2013 15:26:19 -0800 (PST)
Supplementary Orbit Raising Manoeuvre Planned for Mars Orbiter Spacecraft
IRSO Press Release
November 11, 2013
In the fourth orbit-raising operation conducted this morning (Nov 11,
2013), the apogee (farthest point to Earth) of Mars Orbiter Spacecraft
was raised from 71,623 km to 78,276 km by imparting an incremental
velocity of 35 metres/second (as against 130 metres/second originally
planned to raise apogee to about 100,000 [1 lakh] km). The spacecraft is
in normal health. A supplementary orbit-raising operation is planned
tomorrow (November 12, 2013) at 0500 hrs IST to raise the apogee to
nearly 1 lakh km.
During the orbit-raising operations conducted since November 7, 2013,
ISRO has been testing and exercising the autonomy functions
progressively, that are essential for Trans-Mars Injection (TMI) and
Mars Orbit Insertion (MOI).
During the first three orbit-raising operations, the prime and redundant
chains of gyros, accelerometers, 22 Newton attitude control thrusters,
attitude and orbit control electronics as well as the associated logics
for their fault detection isolation, and reconfiguration have been
exercised successfully. The prime and redundant star sensors have been
functioning satisfactorily. The primary coil of the solenoid flow
control valve was used successfully for the first three orbit-raising
During the fourth orbit-raising operations held today (November 11,
2013), the redundancies built-in for the propulsion system were
exercised, namely, (a) energising the primary and redundant coils of the
solenoid flow control valve of 440 Newton Liquid Engine and (b) logic
for thrust augmentation by the attitude control thrusters, when needed.
However, when both primary and redundant coils were energised together,
as one of the planned modes, the flow to the Liquid Engine stopped. The
thrust level augmentation logic, as expected, came in and the operation
continued using the attitude control thrusters. This sequence resulted
in reduction of the incremental velocity.
While this parallel mode of operating the two coils is not possible for
subsequent operations, they could be operated independently in sequence.
Received on Mon 11 Nov 2013 06:26:19 PM PST