Mangalyaan Clears Crucial Test - the main engine has a "perfect burn"

[janon]

India's Mars Orbiter, Mangalyaan Clears Crucial Test

India's Mars orbiter satellite, which has been on an arduous nine-month-long journey to the Red Planet, cleared a crucial test today. The main rocket engine of the satellite, which has been lying dormant for this extended period, was successfully test-fired.

The Indian Space Research organisation or ISRO confirmed that the engine had a "perfect burn' and the trajectory has also been corrected. Now all systems are set for the big event on September 24, the day Mangalyaan is set to enter the Martian orbit. (Also Watch: Mangalyaan Healthy, Team Cool, says ISRO Chief to NDTV)

Launched on November 5 last year, Mangalyaan has been successfully braving the rough weather in space. The satellite carries one large rocket motor and eight smaller thrusters. (Watch the Video)

ISRO Chairman K Radhakrishnan had earlier told NDTV, "We have done a lot of ground simulations and hope that the four-second test will slow the satellite down and correct its trajectory as well in a two-in-one operation". (Mangalyaan Faces Four-Second Trial by Fire)

The big rocket motor on board Mangalyaan had performed flawlessly in over two dozen earlier missions since 1992, and scientists were confident that this time too, things would go as per the plan.

"All commands have been uploaded and the satellite will perform the tasks automatically," Mission controller B N Ramakrishna had said.

There were two parallel circuits to start up the larger rocket motor; ISRO had used these two paths sequentially as part of plan A and plan B. In case the trial had failed, the engineers even had a Plan C to fall back on; they would have used the tiny thrusters to slow down the satellite and still try to reach an orbit of Mars.

The Mangalyaan is laced with eight small rockets and one big rocket. The bigger one had been on an extended slumber, one comparable to that of the sleeping demon 'Kumbhakaran'. But now, it has been 'woken up' for a few seconds in a risky, but successful, operation by the ISRO.

 

[skynet]

good news

 

[HariPrasad]

Its done. Major hurdle overcome.

 

[SrNair]

So now we have a technology to develop a system and engine that can be dormant for 1 year and then to restart .
Kudos to ISRO

 

[Kinetic]

Congrats... waiting fr 24th...

 

[Sam Manekshaw]

Excellent news....waiting for " The Day that Shook the world"

 

[SouthDesi]

PM Modi will join scientists on 24 sept 5.30 am at ISRO,Western Bengaluru to be part of #HistoricalMoment.

That means, it will be a successful event.

 

[Desi_Dalek]

Congrats to ISRO. I am Eagerly waiting for the 24th.

 

[RKO]

Go.... go ..MoMmy

 

[anant_s]

Mars Orbiter Spacecraft completes Engine Test, fine-tunes its Course

India's Mars Orbiter Spacecraft completed an important course correction on Monday that also acted as a demonstration of its main engine that will be tasked with the crucial Mars Orbit Insertion burn planned on Wednesday. With Monday's firing going according to plan, the Indian Space Research Organization can press ahead with "Plan A" - performing the maneuver with the Liquid Apogee Motor instead of using the backup procedure of firing the smaller attitude control thrusters. The Mars Orbit Insertion Burn is planned to begin at 1:47 UTC on Wednesday.

Over the past several days, the Mars Orbiter continued onward in its solar orbit before entering the Martian Sphere of influence around 1 UTC on Monday. In this 577,000-Kilometer sphere around the planet, Mars creates the primary gravitational force acting on an object. With its path changing into a hyperbola centered on Mars with a periapsis altitude of approximately 723 Kilometers, MOM prepared for the mission's final Trajectory Correction Maneuver.

Monday's Liquid Apogee Motor burn served two purposes - a minor Trajectory Correction Maneuver further refining the craft's approach trajectory, and secondly, a test of the LAM engine, the second set of propellant lines, valves and regulators to ensure the engine will be operational for the critical Mars Orbit Insertion burn for which MOM only gets one chance.

At 9:00 UTC on Monday, MOM successfully fired its main engine for a planned duration of 3.968 seconds, achieving a change in velocity of 2.18 meters per second indicating a very slight overperformance as the published burn target was a delta-v of 2.142m/s. The burn was targeted to lower the spacecraft's periapsis altitude to 515 Kilometers to optimize the Mars Orbit Insertion and the resulting elliptical orbit around Mars.

The Indian Space Research Organization confirmed that the Liquid Apogee Motor was successfully fired after sitting idle for 295 days following its last burn on December 1, 2013. This clears the way for MOM's orbital insertion maneuver on Wednesday to follow in the footsteps of NASA's MAVEN spacecraft that entered orbit on Monday.

At the time of MOM's orbital insertion, its signals will take 12 minutes and 28 seconds to travel to Earth for reception by NASA's Deep Space Network Stations in Canberra and Goldstone that will relay the data in real time to ISRO's station in Bangalore so that teams can monitor data as it comes in. However, much of MOM's maneuver takes place behind Mars, as seen from Earth which means that from a point four minutes into the MOI burn until three minutes after the scheduled end of the maneuver, teams on Earth will have no insight into the spacecraft's progress.

The critical Mars Orbit Insertion Burn Sequence will begin three hours ahead of the planned maneuver time when the spacecraft automatically switches over to its Medium Gain Antenna for communications since the High Gain Antenna will be pointing away from Earth during the retrograde burn.

21 minutes ahead of ignition, the spacecraft will begin the re-orientation to the proper attitude for the burn, pointing LAM to the direction of travel. The re-orientation is accomplished using the vehicle's Reaction Wheels. Five minutes and 13 seconds ahead of the burn, the spacecraft passes into darkness - for the first time since leaving Earth last year. In advance, MOM will fully charge its battery to be in a safe configuration for the eclipse.

Three minutes ahead of the burn, the vehicle's eight 22-Newton thrusters are enabled to start providing attitude control which they will continue to do throughout the main engine burn, keeping MOM pointing forward.
Ignition of the Liquid Apogee Motor is planned at 1:47:32 UTC on Wednesday, September 24, 7:17 Indian Standard Time. The Mars Orbit Insertion burn has a planned duration of 24 minutes and 14 seconds, slowing the spacecraft down by 1,098.7 meters per second to be captured in an elliptical orbit around Mars. During the burn, the engines will consume 249.5 Kilograms of propellant leaving only about 40 Kilograms of propellant for the rest of the mission.

MOM is targeting an insertion orbit of 423 by 80,000 Kilometers at an inclination of 150 degrees with an orbital period of more than three days.

Should something go wrong during the burn, MOM is programmed to react appropriately in order to achieve a stable orbit around Mars - even if that means to spend all the vehicle's propellant to do so. In the event the Liquid Apogee Motor is not ignited or its burn is cut short, MOM would automatically switch to the 22-Newton thrusters to supply as much delta-v as possible. Due to their lower thrust, the 22N thrusters would need to fire much longer than LAM along a greater stretch around the periapsis pass which will increase propellant consumption and leave MOM in a higher orbit.

The thrust augmentation by the 22N thrusters was first tested in November 2013 and worked as planned with the thrusters continuing to fire after LAM cutoff to optimize MOM's trajectory as best as possible.

Teams are hopeful that everything will go according to plan on Wednesday, given the extremely good performance of the spacecraft over the course of its mission. With the Liquid Apogee Motor firing, MOM will disappear behind Mars, as seen from Earth, at MOI+4 minutes and 18 seconds. Shortly thereafter, MOM will stop sending telemetry since it wouldn't be heard on Earth anyway. Confirmation of a good burn start will be given when signals from ignition arrive at Earth at 2:00:00 UTC.

MOM will head out of eclipse at 2:07:01 UTC while its engine is still firing. After the vehicle's navigation platform senses a delta-v of 1,098.7m/s, MOM will shut down its engine. LAM Cutoff is expected at 2:11:46 UTC. One minute after cutoff, MOM will begin to maneuver back to its communications orientation, pointing the High Gain Antenna to Earth.

27 minutes and 38 seconds after the start of the Mars Orbit Insertion burn, MOM will appear again and begin sending signals back to Earth a little under three minutes later.
At that point, Deep Space Network stations will be standing by to pick up the spacecraft and relay telemetry to India while also performing an initial doppler measurement to quickly assess whether the vehicle is on the planned trajectory.

Recorded burn data will be downlinked to allow Mission Controllers to assess the success of the burn by means of the analysis of engine and attitude control performance. A final confirmation of orbital insertion will come a few hours after the event when initial orbital data can be computed from doppler tracking.

After arriving in orbit, MOM will go through a series of reconfigurations to re-power some of its systems. For its first day in orbit, MOM already has a schedule of operations in its memory that include the acquisition of a photo of the red planet with the Mars Color Camera. A few commissioning and checkout operations are planned over the coming weeks to prepare MOM's instruments for science operations - the Lyman Alpha Photometer, the Martian Exospheric Neutral Composition Analyzer, the Methane Sensor for Mars, and the Thermal Infrared Imaging System.

Press release from ISRO

The 440 Newton Liquid Apogee Motor (LAM) of India's Mars Orbiter Spacecraft, last fired on December 01, 2013, was successfully fired for a duration of 3.968 seconds at 1430 hrs IST today (September 22, 2014). This operation of the spacecraft's main liquid engine was also used for the spacecraft's trajectory correction and changed its velocity by 2.18 metre/second. With this successful test firing, Mars Orbiter Insertion (MOI) operation of the spacecraft is scheduled to be performed on the morning of September 24, 2014 at 07:17:32 hrs IST by firing the LAM along with eight smaller liquid engines for a duration of about 24 minutes.

Welcome To ISRO :: Press Release ::
September 22, 2014

 

[arp2041]

It should have been NAMED "Mir-reegh Sawaari" Instead

 

[mike2000]

Congrats on this achievement India,
The Only remaining thing now is to develop your own deep space network stations so you can be fully independent. I admire countries who strive for self sufficiency despite the hurdles they might face. I know it's not easy.
So congrats again to all Indian members on here. This is not an easy task. Kudos.

 

[ganimi kawa]

Now, waiting for 24th morning! Godspeed !

 

[thesolar65]

India's Mars Orbiter, Mangalyaan Clears Crucial Test

Yeah, perfect Engine burn and many "Heart Burns"...

 

[Nova2]

Congrats on this achievement India,
The Only remaining thing now is to develop your own deep space network stations so you can be fully independent. I admire countries who strive for self sufficiency despite the hurdles they might face. I know it's not easy.
So congrats again to all Indian members on here. This is not an easy task. Kudos.

India has a Deep Space Network since 2008 and was used to track Chandrayan 1 & is now being used to track MoM,though at times it works in collaboration with NASA's DSN.

Indian Deep Space Network - Wikipedia, the free encyclopedia

Wish'em luck ,can't wait to see that thing dance around mars