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== Overview ==
 
== Overview ==
The Lunar Reconnaissance Orbiter (LRO) is the first mission in NASA's planned return to the moon. LRO is scheduled to launch 24th April, 2009, with the objectives to finding safe landing sites, locate potential resources, characterize the radiation environment and test new technology.
+
The Lunar Reconnaissance Orbiter (LRO) is the first mission in NASA's planned return to the moon. LRO will launch Feb. 27, 2009, with the objectives to finding safe landing sites, locate potential resources, characterize the radiation environment and test new technology.
  
 
The return to the moon will enable the pursuit of scientific activities that address our fundamental questions about the history of Earth, the solar system and the universe -- and about our place in them. It will allow us to test technologies, systems, flight operation and exploration techniques to reduce the risk and increase the productivity of future missions to Mars and beyond. It will also expand Earth's economic sphere to conduct lunar activities with benefits to life on our home planet.
 
The return to the moon will enable the pursuit of scientific activities that address our fundamental questions about the history of Earth, the solar system and the universe -- and about our place in them. It will allow us to test technologies, systems, flight operation and exploration techniques to reduce the risk and increase the productivity of future missions to Mars and beyond. It will also expand Earth's economic sphere to conduct lunar activities with benefits to life on our home planet.
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The debris plumes are expected to be visible from Earth- and space-based telescopes 10-to-12 inches and larger.
 
The debris plumes are expected to be visible from Earth- and space-based telescopes 10-to-12 inches and larger.
  
This is a difficult and challenging mission. Experienced orbinauts will enjoy the challenge of targeting the LCROSS to impact the North Pole of the moon, when the LRO spacecraft is overhead. This mission is not recommended for people recently starting to use Orbiter. Familiarity with setting up gravity assist maneuvers in TransX is a '''required''' skill.
+
This is a difficult and challenging mission. Experienced orbinauts will enjoy the challenge of targeting the LCROSS to impact the south pole of the moon, when the LRO spacecraft is overhead. This mission is not recommended for people recently starting to use Orbiter. Familiarity with setting up
 +
gravity assist maneuvers in TransX is a '''required''' skill.
 
=== Mission Objectives ===
 
=== Mission Objectives ===
  
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Earth’s closest neighbor is holding a secret. In 1999, hints of that secret were revealed in the form of concentrated hydrogen signatures detected in permanently shadowed craters at the lunar poles by NASA’s Lunar Prospector. These readings may be an indication of lunar water and could have far-reaching implications as humans expand exploration past low-Earth orbit. The Lunar CRater Observing and Sensing Satellite (LCROSS) mission is seeking a definitive answer.
 
Earth’s closest neighbor is holding a secret. In 1999, hints of that secret were revealed in the form of concentrated hydrogen signatures detected in permanently shadowed craters at the lunar poles by NASA’s Lunar Prospector. These readings may be an indication of lunar water and could have far-reaching implications as humans expand exploration past low-Earth orbit. The Lunar CRater Observing and Sensing Satellite (LCROSS) mission is seeking a definitive answer.
  
=== Required add-ons ===
+
=== required add-ons ===
* [http://users.kymp.net/p501474a/Orbiter/Orbiter.html IMFD 4.2.2]
+
* [http://orbithangar.com/searchid.php?ID=2601 Atlas V heavy] V2 by Kev33
* [http://orbithangar.com/showAddon.php?id=f12093c1-4d5e-4a57-b2e2-427a205f82ee Multistage2015 for Orbiter 2010] (install the add-on and copy "Multistage2015.dll" under the "Modules" folder to "Multistage2.dll")
+
* [http://koti.mbnet.fi/jarmonik/Orbiter.html IMFD 5.1m]
  
=== Optional add-ons ===
+
=== optional add-ons ===
  
 
* [http://orbithangar.com/searchid.php?ID=3165 Attitude MFD]  
 
* [http://orbithangar.com/searchid.php?ID=3165 Attitude MFD]  
* [http://orbithangar.com/searchid.php?ID=3434 Level 9 Lunar Texture] or [http://www.orbithangar.com/searchid.php?ID=3570 Moon3d by BrianJ]
+
* [http://www.orbithangar.com/searchid.php?ID=2989 Telescope MFD]
 
+
* [http://orbithangar.com/searchid.php?ID=3434 Level 9 Lunar Texture]
== Spacecraft Specifications ==
 
 
 
'''LRO'''
 
*Empty Mass 809kg
 
*Fuel Mass 897kg, ISP 2100Ns/kg
 
*Main Engine 352N
 
*RCS 20N
 
 
 
 
 
'''LCROSS'''
 
*Empty Mass 592kg
 
*Fuel Mass 300kg, ISP 2200Ns/kg
 
*Retro Engine 44N
 
*RCS 4.5N
 
 
 
 
 
'''AV020Centaur'''
 
*Empty Mass 1914kg
 
*Fuel Mass 20672kg, ISP 4200Ns/kg
 
*Main Engine 99400N
 
*RCS 1000N
 
 
 
'''NOTE''': When AV020Centaur fuel is finished, control is automatically switched to LCROSS propulsion system.
 
 
 
== Spacecraft Controls ==
 
Available commands are displayed on the top-left of the vessel HUD
 
 
 
'''AV020Centaur'''
 
 
 
{{Key|P}} = Toggle Parking Orbit Autopilot On/Off<br>
 
{{Key|J}} = Jettison LRO<br>
 
{{Key|B}} = Manual Purge Centaur Fuel (automatic at 32000km alt.)<br>
 
{{Key|K}} = Jettison LCROSS<br>
 
{{Key|V}} = Deploy/Delete LCROSS "Bullseye" target on Moon N.Pole<br>
 
{{Key|N}} = Display LRO Lunar Orbit Data<br>
 
{{Key|M}} = TransX cheat! Enable 44N "ghost" Main Engine for use with TransX
 
 
 
 
 
'''LRO'''
 
 
 
{{Key|G}} = Deploy Antenna (automatic Earth tracking)<br>
 
{{Key|K}} = Deploy Solar Panel (automatic Sun tracking)<br>
 
{{Key|N}} = Activate Laser Altimeter<br>
 
{{Key|V}} / {{Key|Shift}}{{Key|V}} = Rotate DLRE Azimuth<br>
 
{{Key|B}} / {{Key|Shift}}{{Key|B}} = Rotate DLRE Elevation
 
 
 
 
 
'''LCROSS'''
 
 
 
{{Key|F8}} = View from Visual Context Imager (6 deg FOV)
 
 
 
 
 
'''LC-41 (Launch Pad)'''
 
 
 
{{Key|V}} = LOX Vent On/Off<br>
 
{{Key|K}} = Lights Off<br>
 
'''NOTE:''' LC-41 is automatically deleted when focus vessel is above 100km alt.
 
 
 
== Add-on Notes and Quick Info ==
 
'''NOTES'''
 
 
 
''Moon Orientation''<br>
 
The precession of the Moon's axis is not modelled in Orbiter. To ensure accuracy of the Moon's orientation at the time of the mission, the LRO add-on uses a custom sol.cfg and moon.cfg located in the Config/LRO/ directory. To use them, the "Environment" entry in the scenario file must point to the LRO/sol.cfg.
 
e.g.
 
BEGIN_ENVIRONMENT
 
  '''System LRO/Sol'''
 
  Date MJD 54892.2256944444
 
END_ENVIRONMENT
 
 
 
 
 
''Launch Date''<br>
 
Although the launch is currently scheduled for 24th April 2009, the primary launch scenario provided in this add-on is the 27th April 2009 due to the mission constraints on the LAN of LRO's final Lunar orbit. The second launch scenario provided is for the 24th April 2009, should you wish to use it.
 
 
 
''Transx version''<br>
 
This document assumes the default Transx version supplied with Orbiter. Other versions may give different lunar intercept times.
 
 
 
 
 
'''QUICK INFO'''
 
 
 
''LRO''<br>
 
Final Lunar orbit - 30km x 70km, 90deg inclination(Equatorial), Periselene over South Pole,<br>
 
LAN = 38deg(Ecliptic) +/- 17deg(max.)
 
 
 
 
 
''LCROSS/AV020Centaur''<br>
 
Uses Lunar flyby to reach high-inclination Earth orbit,<br>
 
Spacecraft:Moon orbit resonance 2:3 (other resonances possible)
 
 
 
Impact chosen target at North Pole of Moon (targets designated by surface bases "Lcross_A" to "Lcross_E"),  impact speed ~2.5km/s, impact angle > 60deg.
 
 
 
Lcross separates from AV020Centaur at impact -9hrs. Lcross impact 4mins after AV020Centaur.
 
 
 
Impact should be timed to be visible by LRO passing over and by ground-based observers in Hawaii during hours of darkness.
 
  
 
== Procedures ==
 
== Procedures ==
 
Accuracy of burns in this mission is '''CRITICAL'''.  
 
Accuracy of burns in this mission is '''CRITICAL'''.  
 +
During this mission, especially after the TLI burn, we will be using the tools TransX or IMFD to get the '''DIRECTION''' of our burns, and using IMFD map to monitor in real time the '''MAGNITUDE''' of the DeltaV we are imparting. For this mission, usually the AUTOBURN button is '''NOT''' your friend.
  
 +
You may wish to edit your config/Moon.cfg file and change the LAN line to
 +
LAN = 2.2483                    ; ascending node of equator - CHECK!
 +
This will ensure a more accurate simulation. 
 
=== Launch ===
 
=== Launch ===
  
Fire up the '''01 - AV020 LRO launch 27Apr''' scenario in the LRO scenarios folder
+
Fire up the '''01 - AV020 LRO launch''' scenario in the LRO scenarios folder
 
This is a night launch so visibility is poor until after the TLI burn.  
 
This is a night launch so visibility is poor until after the TLI burn.  
The scenario starts at UTC 04/27/2009 04:09:00.
+
The scenario starts at UTC 2/28/2009 2:07:00.
Launch time is UTC 04:10:11.
+
Launch time is UTC 2:08:07.
The default camera view is Ground Observer. You have just over a minute to set up the camera to your personal preference.
+
The default camera view is Ground Observer. You have just under a minute to set up the camera to your personal preference.
  
  At UTC 04:10:01 press the '''p''' key to start the launch countdown and
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  <nowiki>At UTC 2:07:57 press the</nowiki> '''p''' <nowiki>key to start the launch countdown.</nowiki>
1st stage auto-pilot.
 
  
 
At T-5 seconds, engine ignition will happen, and the hold down clamps release at T-0.
 
At T-5 seconds, engine ignition will happen, and the hold down clamps release at T-0.
The Atlas V-401 1st stage autopilot will continue until 1st stage seperation.It can be disengaged by Pressing '''p''' again, but this is not recommended.
+
The Atlas V-401 booster has a launch autopilot to guide you until booster cutoff. Pressing '''p''' again will disable the autopilot, but this is '''NOT''' recommended, as the booster has no RCS control.
  
  <nowiki>10 seconds after 1st stage separation, press the</nowiki> '''p''' <nowiki>key again.</nowiki>
+
  <nowiki>10 seconds after booster separation, press the</nowiki> '''p''' <nowiki>key again.</nowiki>
  
This will ignite the 2nd stage Centaur engine, and engage the 2nd stage autopilot which will put the vehicle in a circular 185km parking orbit. Pressing '''p''' again will disengage the 2nd stage autopilot.
+
This will ignite the second stage Centaur engine, and engage the second state autopilot. Pressing '''p''' again will disengage the second stage autopilot,
 +
but again, this is not recommended. While the second stage does have RCS control, the autopilot will put the vehicle in a circular 185km parking orbit.
  
Shortly after 2nd stage ignition, the fairing will be automatically jettisoned, and the LRO/LCROSS spacecraft will be exposed.
+
Shortly after second stage ignition, the fairing will be jettisoned, and the LRO/LCROSS spacecraft will be exposed.
  
 
=== TLI ===
 
=== TLI ===
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  Also, click the '''HUD''' button in the right ''orbit'' MFD so that your HUD is set to orbit reference Earth
 
  Also, click the '''HUD''' button in the right ''orbit'' MFD so that your HUD is set to orbit reference Earth
Click the '''Prograde''' button to engage the prograde autopilot.
 
  
 
==== IMFD Configuration set-up ====
 
==== IMFD Configuration set-up ====
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  Click '''Set'''
 
  Click '''Set'''
 
  Click '''Tgt''' and enter '''Moon'''
 
  Click '''Tgt''' and enter '''Moon'''
  Click '''Nxt''' 6 times so that ''Off Plane'' is highlighted.
+
  Click '''Nxt''' so that the ''Tej'' parameter is highlighbted.
Click '''+''' twice to change it to ''Source Plane''.
+
  Click + or - repeately until the ''dV'' parameter reaches a minimum. This should be about ''3.13k''
Click '''Prv''' so that ''Realtime'' is higlighted.
+
  Click '''Pg''', then '''BV''', then '''AB'''
Click '''+''' to change it to ''Off-Axis''
 
Click '''Prv''' twice so that ''TIn'' is highlighted.
 
Click '''+''' or '''-''' repeatedly to minimize the value of ''PlC'' in the lower left section of the MFD.
 
You may want to click on '''ADJ''' and set it to ''10x'' for this adjustment.
 
Be sure to set it back to ''1x'' when finished.
 
Click '''Prv''' twice so the ''Tej'' parameter is highlighted.
 
  Click '''+''' or '''-''' repeatedly until the ''EjA'' parameter is about 3 degrees.  
 
If you go much below 3 degrees the ''Off-Axis'' parameter will change back to ''Realtime'',
 
and we need to be in ''Off-Axis'' mode.
 
The ''dV'' parameter should be about ''3.15k'' at this point.
 
Select IMFD in the right MFD also.
 
Click '''MNU''', then '''PG'''. Enter '''0''' for the ''MFD ID''. Click '''Map'''.
 
Click '''Tgt''', and enter '''Moon'''. Click '''PG''', then '''Plan'''.
 
Clidk '''PG''', then click '''Sel''' until Ref Moon appears in yellow text.
 
Click '''MOD''' 3 times, then click '''Nxt''' so that ''Accuracy'' is highlighted.
 
Click '''-''' twice so that ''accuracy'' is set to ''Max''.
 
Click '''MOD''' twice to return to the map display with equatorial parameters.
 
Wait until the ''TEj'' parameter in the left display is ''1k'' or less.
 
  In the left MFD, Click '''MOD''', and ''Offset Disabled'' should be highlighted.
 
Click '''+''' twice and ''Vel. Frame'' should be displayed. Click '''Nxt''' until ''Lon'' is highlighted.
 
Click '''Set''' and enter '''65'''. Click '''Nxt''' and ''Lat'' should be highlighted.
 
Click '''Set''' and enter '''-59.8'''. Click '''Nxt''', then '''Set''', and enter '''20.3M''' for ''Rad''.
 
Adjust the ''Rad'' and ''Lat'' parameters to get the ''PeA'' and ''EqI'' parameters in the right MFD as close
 
as possible to ''350k'' and ''90'' degrees. Repeat as necessary. Click '''Pg''', then '''BV''', then '''AB'''.
 
Disengage the ''Prograde'' autopilot.
 
 
 
[[Image:Lrotli.jpg|frame|left|IMFD setup for the TLI burn]] [[Image:Lrotli2.jpg|frame|right|IMFD setup for the TLI burn]]
 
 
 
 
 
 
 
  
 +
Sit back and wait for the burn. You may wish to use time acceleration to get close to the burn time, but set it back to 1x acceleration once you get close.
  
 +
''Note for Brian: It may be possible to use an offset in IMFD to target a polar orbit in the TLI. I think AMSO does something like this. It might be worth checking out, but it may make the LCROSS targeting harder. ''
  
 +
When the TLI burn is complete, click on the '''BV''' button to restore the main IMFD Course target intercept screen
  
 +
'''Do not jettison LRO yet'''
  
 +
=== Lunar targeting/LRO ===
  
 +
When you reach 32M altitude above the Earth, a piece of orbital debris will puncture the fuel tank of the centaur and drain all of its fuel. It is '''critical''' that you get your targeting done for both LRO and LCROSS before this time, as once that happens, your deltaV budget is severely limited.
  
 +
At about 21M altitude above the earth, select TransX in the Right MFD.
  
 +
Click on the '''--''' button until the target is ''Moon''
 +
Click '''VW''' once so the View is ''Manoevre''
  
 +
Select TransX also in the Left MFD.
  
 +
In the Left MFD click '''FWD''', then '''VW''', so that the view is 'Encounter'
 +
In the Right MFD click '''++''' so Manoevre mode is ''On''
 +
Click '''VAR''' 5 times so that ''Ch. Plane vel.'' is displayed
 +
Click '''ADJ''' so that ''Medium'' adjustment mode is entered.
 +
Click '''--''' until the ''Min Alt.'' parameter in the Left MFD is over 50k
  
 +
Our goal here is to end up with an ''Inclination'' parameter in the left MFD as close as possible to 90 degrees, and the ''Min Alt.''  parameter as close as possible to 50k.
  
 +
In the Right MFD click '''VAR''' 3 times so that ''Prograde Vel'' is selected.
 +
Click on '''ADJ''' 3 times  for ''Super'' adjustment mode.
 +
Click on '''++''' or '''--''' until ''Min Alt.'' is close to 50k and ''Inclination'' is close to 90 degrees in the Left MFD.
  
 +
Keep repeating these adjustments, using finer adjustment modes until you get as close as possible to the required parameters. Work quickly though, as the orbital debris is getting closer and we still have to target the LCROSS spacecraft.
  
 +
In the Right MFD click '''VW''' to get ''Target view''
 +
Use rotation mode to get the cross as close as possible to the center of the target.
 +
'''Do NOT make the burn yet'''
  
 +
Use the planetarium view '''F9''' key to make sure you are pointed in a generally northerly direction (towards Polaris + or - 30 degrees or so)
 +
If you are pointed in a southerly direction, the transx targeting will have to be re-done using '''++''' Ch. plane vel. instead of '''--'''
  
 +
Set the Left MFD to IMFD.
  
 +
Press the '''MNU''' button and select Map mode.
 +
Press the '''TGT''' button and enter '''Moon'''
 +
Press the '''Sel''' button until ''Ref Moon'' is displayed.
  
 +
Watch the PeA parameter as you make a low dV burn with the Centaur engine '''Ctrl-numpad +''' When the Pea gets to +50k, STOP the burn with the
 +
'''numpad *''' key. As it gets close you may with to use translation mode and the '''numpad-6''' key. There is no reverse translation. Don't overshoot by very much, if at all. Some dV will be added by LRO jettison which we will have to correct later.
  
 +
Press the '''j''' key to jettison LRO.
  
 +
On the Right MFD click '''VW''' twice to get back to ''Maneuver view''
 +
Click '''VAR''' until Maneuver Mode is displayed.
 +
Click '''++''' to turn Maneuver mode ''Off''
  
 +
=== Lunar targeting/LCROSS ===
  
 +
* Swingby of moon is passive (no thrusting)
 +
* 81 days in post-swingby cruise orbit
 +
* Current baseline is 3-month trajectory with south pole impact
 +
* Two revolutions in high ecliptic inclination (~50 deg), 40-day period Earth orbit
 +
       
 +
  
 +
After the LRO is jettisoned, swing the Centaur around 180 degrees. Use the finely graduated scale on the hud, or Attitude MFD
 +
to do this. When the Centaur is pointed 180 degrees from where it was when you made the LRO targeting burn, make another small burn, again watching
 +
IMFD map so that the final PeA is about 2M on the opposite side of the moon. Select IMFD on the right MFD
  
 +
Click '''MNU''', then '''Course'''. Click '''NXT''' 4 times so that ''Delta Velocity'' is highlighted. Click '''Set'''.
 +
Click on '''TGT''' and enter '''Moon''' as the target. Click '''Nxt''' 5 times so that ''dVf'' is highlighted.
 +
Click '''Set''' and enter '''0'''.
  
 +
In the Left MFD click '''PG''' then '''Plan'''. The green line of our orbit should turn blue.
 +
In the Right MFD click '''+''' repeatedly. The ''RIn'' parameter in the Left MFD should increase. If not, Click '''-''' until it does.
 +
Also watch the ''PeA'' parameter. Do not let it go negative.
  
 +
When ''PeA'' gets too low, click '''Nxt''' on the Right MFD so that ''dVp'' is highlighted.
 +
Click '''-''' until ''PeA'' in the Left MFD is back to around 2M. Setting '''Adj''' to 10x may be necessary, but return it to 1x when finished.
  
Sit back and wait for the burn. You may wish to use time acceleration to get close to the burn time, but set it back to 1x acceleration once you get close.
+
Keep repeating these adjustments until ''Rin'' is close to 90 degrees and ''PeA'' is close to 2M. This is just a ball bark "rough in" to make our transx tageting easier. The numbers do not have to be exact. '''Work quickly''' though. Liberal use of the '''Pause''' function is encouraged.  
When the TLI burn is complete, click on the '''BV''' button to restore
 
the main IMFD Course target intercept screen. Click '''MOD''', then '''Prv'''
 
until ''Vel. Frame'' is highlighted. Click '''+''' so that '''Offset Disabled''' is shown.
 
Click '''MOD''' three times to return to the main target intercep screen.
 
Also, in the right MFD, click '''Pg''', then '''Plan''' to disengage plan mode.
 
  
  Press the '''j''' key to jettison LRO.
+
  In the Right MFD, click '''Pg''', then '''BV'''.
Switch focus back to LRO.
 
Press the '''k''' key to deploy the LRO solar panels
 
Once the panels have fully unfolded, and rotated to face the sun,
 
press the '''g''' key to deploy the antenna
 
  
=== Lunar targeting/LCROSS ===
+
Use rotation mode to align the cross in the center of the target and then select translation mode and use ''CTRL-numpad +''' to burn until ''BT'' is close to ''0''. AutoBurn is not recommended.
* Swingby of moon is passive (no thrusting)
 
* 84 days in post-swingby cruise orbit
 
* Current baseline is a '''3 Lunar orbit:2 Spacecraft orbit''' trajectory with north pole impact
 
* Two revolutions in high ecliptic inclination (~50 deg), 42-day period Earth orbit
 
  
When you reach 32M altitude above the Earth, the Centaur engine will automatically purge of all fuel and control switches over to the LCROSS propulsion system. You may initate the engine purge manually by pressing '''B'''. It is '''critical''' that you get your targeting done for LCROSS before this time, as once that happens, your deltaV budget is severely limited.
+
Once this is done, in the Left MFD click '''PG''', then '''Plan''', so the orbit line turns green again.  
  
Switch focus to AV020Centaur. Select Orbit MFD in the right MFD.
+
Select Transx in both MFD's.Select moon as the target in the right MFD, as in the LRO targeting.  
At about 21M altitude above the earth, select IMFD in the Right MFD.
 
Click '''MNU''', then '''Map'''. Make sure Target is ''Moon'', and ''Ref moon'' is displayed.
 
Click '''MOD''' three times, and set ''Accuracy'' to ''Max''.
 
Click '''MOD''' again to return to the map display.
 
Use rotational thrusters to point the Centaur in a northward direction. (Towards Polaris)
 
Switch to translation mode and use linear thrusters until PeA in the Right MFD is about 2M.
 
In the left MFD be sure ''Target Intercept'' is highlighted.
 
Click '''+''', then '''Nxt''' four times until ''Delta Velocity'' is highlighted.
 
Click '''Set'''. Click '''TGT''', and type '''Moon'''.
 
Click '''Nxt''', then '''Set''', and set ''TEj'' to '''400'''.
 
Click '''Nxt''' three times until ''dVf'' is highlighted.
 
Click '''Set''', and enter '''0'''.
 
in the Right MFD, click '''Plan''' so the green course line turns blue.
 
In the left MFD, adjust ''dVp'' and ''dVf'' so that ''RIn'' and ''PeA'' in the right MFD
 
are as close as possible to ''90'' degrees, and ''1.5M'', respectively.
 
Click '''Prv''' until ''TEj'' is highlighted and set it to '''0'''.
 
Click '''PG''', '''BV''', and '''AB'''.
 
When the burn is finished, click '''BV''', and '''PG''' in the left MFD, and '''Plan''' in the right MFD.
 
Select Transx in both MFDs.
 
Select moon as the target in the right MFD
 
  
 
  Click the '''FWD''' button for stage 2, make sure the view is ''Setup'' and select the target as ''Escape''.
 
  Click the '''FWD''' button for stage 2, make sure the view is ''Setup'' and select the target as ''Escape''.
Line 275: Line 176:
  
 
There will be a green line extending from the center of the moon to hopefully past the edge. This is an edge-on view of our current approach to the moon.
 
There will be a green line extending from the center of the moon to hopefully past the edge. This is an edge-on view of our current approach to the moon.
We need to fine tune this approach to give us a lunar gravity assist which will result in a highly inclined orbit around the earth with a period of 42 days
+
We need to fine tune this approach to give us a lunar gravity assist which will result in a highly inclined orbit around the earth with a period of 40 days
  
 
  On the Right MFD, click the '''VAR''' button twice to bring up the ''Inc. angle'' parameter
 
  On the Right MFD, click the '''VAR''' button twice to bring up the ''Inc. angle'' parameter
  Click on '''++''' several times until the dotted yellow orbit is about the same size as the solid green line.  
+
  Click on '''--''' several times until the dotted yellow orbit is about the same size as the solid green line.  
 
  It does not have to be superimposed in the same place, but of a similar diameter.
 
  It does not have to be superimposed in the same place, but of a similar diameter.
  
 
On the Left MFD the dotted yellow line should be on the same side (more or less) of the moon as the green line. If it is on the opposite side,
 
On the Left MFD the dotted yellow line should be on the same side (more or less) of the moon as the green line. If it is on the opposite side,
click on the '''--''' button until it is on the same side.
+
click on the '''++''' button until it is on the same side.
  
 
  On the Right MFD, click on '''VAR''' four times until the ''outward angle'' parameter is shown.
 
  On the Right MFD, click on '''VAR''' four times until the ''outward angle'' parameter is shown.
  Adjust this parameter, and the Inc. angle parameter until the dotted line is superimposed  
+
  Adjust this parameter, and the Inc. angle parameter until the dotted line is superimposed on the solid green line in the slingshot view.
on the solid green line in the slingshot view.
+
 
 +
This is our current trajectory. Now we need to adjust the trajectory to impact the moon in 2 orbits with a 40 day period.
  
This is our current trajectory. Now we need to adjust the trajectory to impact the moon in 2 orbits with a 42 day period.
 
Note the angle of this line. We will be adjusting the length of the line,
 
but the angle '''must''' remain the same so that our flight path
 
is over the moons pole.
 
 
  On the Right MFD, click '''VW''' so that the setup view is shown
 
  On the Right MFD, click '''VW''' so that the setup view is shown
 
  Click '''VAR''' 3 times so that ''Orbits to Icept'' is shown
 
  Click '''VAR''' 3 times so that ''Orbits to Icept'' is shown
 
  Click '''++''' 4 times so that the ''Orbits to Icept'' parameter is 2.0
 
  Click '''++''' 4 times so that the ''Orbits to Icept'' parameter is 2.0
  
Now we must figure out what our ''Enc. MJD'' should be. Take the current MJD and add 88.5 to it. (4.5 days to reach the moon, then 2 orbits of 42 days each.) For the 27 April(UTC) launch this would be 54948.2 + 88.5 = 55036.7 . This is the ''Enc. MJD'' we will be shooting for.
+
Now we must figure out what our ''Enc. MJD'' should be. Take the current MJD and add 85 to it. (5 days to reach the moon, then 2 orbits of 40 days each.) For the Feb 28 (UTC) launch this would be 54890 + 85 = 54975. This is the ''Enc. MJD'' we will be shooting for.
  
 
  Click '''VW''' again in the right MFD to get back to ''sling direct'' view.
 
  Click '''VW''' again in the right MFD to get back to ''sling direct'' view.
 
  Adjust the Inc Angle to get as close as possible to the desired MJD.
 
  Adjust the Inc Angle to get as close as possible to the desired MJD.
  When the angle strays too much,
+
  Click '''VAR''' so that ''Outward angle'' is displayed.  
click '''VAR''' so that ''Outward angle'' is displayed.
+
  Click '''ADJ''' twice so that the increment is ''Fine''  
Adjust ''Outward angle'' to bring the lines back into alignment.
 
Repeat the above process, until the date is as close as possible
 
to the target date.  
 
  Click '''ADJ''' so that the increment is ''Fine''  
 
 
  Adjust ''Outward angle'' to get the Cl. App. as close as possible.  
 
  Adjust ''Outward angle'' to get the Cl. App. as close as possible.  
  
My current solution is Inc Angle of 110.99 degrees and Outward angle of -38.1864. Enc MJD is 55036.6951, and Cl. App is 6.726M<br>
+
My current solution is Inc Angle of -115.18 degrees and Outward angle of -47.54. Enc MJD is 54978.5013, and Cl. App is 1.747M<br>
 
Your Mileage may vary.
 
Your Mileage may vary.
  
[[Image:Lcrtgt2.jpg|frame|left|Transx Stage 2]][[Image:Lcrtgt3.jpg|frame|right|Transx stage 3]]
+
Once a solution has been reached, click '''BCK''' twice on the Right MFD. The View should be ''Maneuver'' and Maneuver mode should
 +
be ''off''. Click '''++''' to turn Maneuver mode ''on''
 +
Adjust Prograde Vel. and Ch. Plane vel. until the dotted yellow line on the Left MFD lines up with the solid green line.
 +
R. Inc should be as close as possible to 0, and Pe Ratio should be as close as possible to 1.000.
 +
Once this is done, click '''VW''' in the right MFD to get to ''target view''.
 +
Use rotational thrusters to get the cross in the middle of the target and burn until ''Rel.V'' is as close to 0 as possible.
 +
Click '''VW''' twice to get to maneuver view, Click '''VAR''' to get to ''Maneuver mode'' and turn it off.
 +
Look at the Left MFD to see how you did. Additional corrections may be done as you get closer to the moon.
  
 +
=== Mid course correction/LRO ===
  
 +
Switch focus back to LRO.
  
 +
Press the '''k''' key to deploy the LRO solar panels
 +
Once the panels have fully unfolded, and rotated to face the sun,
 +
press the '''g''' key to deploy the antenna
  
 +
In the Left MFD select IMFD, click on MNU and select Map.
 +
Make sure TgT is Moon, and click Sel until Ref is Moon.
  
 +
Wait until PeT is about 350k<br>
 +
Select IMFD in the Right MFD
  
 +
Click on '''MNU''', then '''Course'''. Click '''Nxt''' 4 times until ''Delta Velocity'' is highlighted, then click '''Set'''.
 +
Click '''Nxt''' 5 times until ''dVf'' is highlighted, click '''Set''' and enter '''0'''.
 +
Click on '''TgT''' and enter '''Moon'''.
 +
In the Left MFD, click '''Pg''', then '''Plan''' so that the green line turns blue.
 +
In the right MFD adjust '''dVp''' and '''dVf''' so that ''RIn'' and ''PeA'' in the left MFD are as close as possible to 90 degrees and 50k respectively
 +
When these adjustments are finished, click '''PG''','''BV''', then '''AB''' in the right MFD.
 +
When the burn completes, click '''Plan''' in the left MFD so the blue line returns to green.
  
 +
Repeat these adjustments as necessary as you get closer to the moon.
  
 +
=== Course correction/LCROSS ===
 +
Switch focus to AV020 Centaur. Select TranxX in both left and right MFDs
  
 +
=== orbit insertion/LRO ===
 +
=== LCROSS orbit correction 1 ===
 +
=== LCROSS final moon targeting ===
 +
=== LCROSS pole targetinjg ===
 +
=== LCROSS LRO targeting ===
 +
* ~7 hours prior to impact, LCROSS will separate from Centaur upper stage and perform a ~10-minute delay maneuver (~30 m/s)  to enable LCROSS to fly through Centaur impact plume
  
 +
== External reference documents ==
  
 
+
[http://lcross.arc.nasa.gov/docs/astrWorkshop/Galal_Orbit_Design_Galal_Final.ppt LCROSS Astronomer Workshop]<br>
 
+
[http://lcross.arc.nasa.gov/ NASA LCROSS page]<br>
 
+
[http://lunar.gsfc.nasa.gov/ NASA LRO page]<br>
 
+
[http://lroc.sese.asu.edu/ ASU LRO Camera Page]<br>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Once a solution has been reached, click '''BCK''' twice on the Right MFD.
 
The View should be ''Maneuver'' and Maneuver mode should
 
be ''off''. Click '''++''' to turn Maneuver mode ''on''
 
Adjust Prograde Vel. and Ch. Plane vel. until the dotted yellow line on the Left MFD
 
lines up with the solid green line.  
 
R. Inc should be as close as possible to 0, and Pe Ratio should be as close as possible to 1.000.
 
Once this is done, click '''VW''' in the right MFD to get to ''target view''.
 
Use rotational thrusters to get the cross in the middle of the target and burn until
 
''Rel.V'' is as close to 0 as possible.
 
Click '''VW''' twice to get to maneuver view, Click '''VAR''' to get to ''Maneuver mode'' and turn it off.
 
Look at the Left MFD to see how you did. Additional corrections may be done as you get
 
closer to the moon.
 
 
 
== See also ==
 
*[[Lunar Reconnaissance Orbiter]]
 
*[[Lunar Reconnaissance Orbiter part 2]]
 
 
 
[[Category:Articles]]
 
[[Category:Orbiter 2010 add-ons]]
 
[[Category:Spacecraft add-ons]]
 
[[Category:Add-ons by BrianJ]]
 
[[Category:Tutorials]]
 

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