Editing Lunar Reconnaissance Orbiter part 2

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  Click '''Sel''' until ''Ref Moon'' is displayed in yellow letters.
 
  Click '''Sel''' until ''Ref Moon'' is displayed in yellow letters.
 
  Click '''MOD''' 3 times and set ''Accuracy'' to ''Max''.
 
  Click '''MOD''' 3 times and set ''Accuracy'' to ''Max''.
  Click '''MOD''' twice to restore Map view showing ''EqI''(equatorial inc) parameter.
+
  Click '''MOD''' twice to restore Map view showing ''EqI'' parameter.
  
 
  In the left MFD, click '''MNU''', then '''Course'''.
 
  In the left MFD, click '''MNU''', then '''Course'''.
 
  Click '''Nxt''' 4 times so that ''Delta Velocity'' is highlighted, and click '''Set'''.
 
  Click '''Nxt''' 4 times so that ''Delta Velocity'' is highlighted, and click '''Set'''.
 
  Click '''TGT''', and enter '''Moon'''.
 
  Click '''TGT''', and enter '''Moon'''.
  Click '''Nxt''', then '''Set''', and set ''TEj'' to '''400'''.
+
  Click '''Nxt''' 5 times so that ''dVf'' is highlighted, click '''Set''', and enter '''0'''.
Click '''Nxt''' three times until ''dVf'' is highlighted.
 
Click '''Set''', and enter '''0'''.
 
 
  In the right MFD click '''PG''', then '''Plan'''.
 
  In the right MFD click '''PG''', then '''Plan'''.
 
  In the left MFD, adjust '''dVf''', and '''dVp''' so that ''EqI'' and ''PeA'' in the right MFD
 
  In the left MFD, adjust '''dVf''', and '''dVp''' so that ''EqI'' and ''PeA'' in the right MFD
  are as close as possible to ''90'' degrees and ''350k'' as possible.  
+
  are as close as possible to ''90'' degrees and ''216k'' as possible.  
 
Be as accurate as possible here. LRO is planning on avoiding a mid-course correction if possible. In orbiter, we will probably still have to do a small
 
Be as accurate as possible here. LRO is planning on avoiding a mid-course correction if possible. In orbiter, we will probably still have to do a small
 
MCC.
 
MCC.
  When your adjustments are done, click '''Prv''' until ''TEj'' is highlighted and
+
  When your adjustments are done, click '''PG''', '''BV''', and '''AB'''.
set it to '''0'''. Click '''PG''', '''BV''', and '''AB'''.
 
 
  When the burn is done, click '''BV''', and '''PG'''. In the Right MFD, click '''Plan''' to turn off plan mode.
 
  When the burn is done, click '''BV''', and '''PG'''. In the Right MFD, click '''Plan''' to turn off plan mode.
  
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  In the left MFD set '''dVp''' and '''dVf''' to '''0'''.
 
  In the left MFD set '''dVp''' and '''dVf''' to '''0'''.
 
  In the right MFD, click '''Plan''' so that the green line turns blue.
 
  In the right MFD, click '''Plan''' so that the green line turns blue.
  In the left MFD adjust '''dVp''' and '''dVf''' so that ''EqI'' and ''PeA'' in the left MFD are as close as possible  
+
  In the left MFD adjust '''dVp''' and '''dVf''' so that ''RIn'' and ''PeA'' in the left MFD are as close as possible  
  to 90 degrees and 350k respectively
+
  to 90 degrees and 216k respectively
 
  When these adjustments are finished, click '''PG''','''BV''', then '''AB''' in the right MFD.  
 
  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.
 
  When the burn completes, click '''Plan''' in the left MFD so the blue line returns to green.
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The LRO main engine is not strong enough to get it into a circular orbit in one try. It will take 4 burns over 12 orbits to achieve the initial 216km x 30km commissioning orbit, with periselene over the South Pole. The first burn is critical in that we must avoid a situation where we are "weakly captured" or not captured at all. The orbit eccentricity at the end of our first burn must be 0.8 or less.  
 
The LRO main engine is not strong enough to get it into a circular orbit in one try. It will take 4 burns over 12 orbits to achieve the initial 216km x 30km commissioning orbit, with periselene over the South Pole. The first burn is critical in that we must avoid a situation where we are "weakly captured" or not captured at all. The orbit eccentricity at the end of our first burn must be 0.8 or less.  
  
When LRO's PeT is about 5k, select IMFD in the left MFD, and Orbit MFD in the right.  
+
When LRO's PeT is about 10k, select IMFD in the left MFD, and Orbit MFD in the right.  
  Click on the '''HUD''' button on the right MFD. Change the MFD to IMFD map mode.
+
  Click on the '''HUD''' button on the right MFD. In the left MFD click '''MNU''', then '''Orbital'''.
Set the '''TGT''' to '''LRO''', '''REF''' to '''Moon'''.
+
  Click '''TgT''', then type '''r'''.
  Click '''PG''', then '''Plan'''.
+
Note that The burn time to a circular orbit is over 4k seconds (over an hour!). Make sure rotational mode is selected.
  In the left MFD select IMFD course, then click on '''PRV''' and select ''Delta Velocity'' mode.  
+
  At 2k seconds to PeT, select Retrograde mode on the hud. When retrograde attitude 
  Click '''REF''' and enter '''Moon''', and click '''TGT''', and enter '''LRO'''.
+
  is established, de-select retrograde mode.
  Select ''dVp'', and click on '''+''' or '''-''' until the ''EqI'' in the right MFD is ''90'' degrees.  
+
  Start the engine by pressing '''numpad-+''' and tap the '''CTRL''' key to keep it burning.
  Click '''PG''', '''BV''', and '''AB'''.
+
Notice that the PeA in the right MFD is decreasing.  
When this burn is finished, in the left MFD
+
  Use the numpad '''1''' and '''3''' keys to move the attitude closer to what the Orbital IMFD mode
set ''TEj'' to '''3k''', and set ''dVf'' to '''-520'''.
+
  thinks it should be until the PeA starts increasing.
In the right MFD, select Orbit MFD. Set '''FRM''' to ''EQU'', and '''PRJ''' to ''Ship''.
+
Keep adjusting the attitude between these points to keep the PeA as close as possible to 216km.  
In the left MFD, adjust '''TEj''' (affects mostly ''PeA'') and '''dVf''' (affects mostly ''ApA'')
+
  When the ApA. parameter in the Right MFD is 3160km, press the '''numpad-*''' key to stop the burn.
  until the ''PeA'' and ''ApA'' as shown in the bottom left of the left MFD are as close
+
The LRO then completes 4 orbits at 3160km x 216km before the next burn,
as possible to ''216k'' and ''3.16M'' respectively.
+
you can switch focus to AV020Centaur and enjoy the view as it passes by the moon.
  Continue these adjustments until both parameters are as close as possible.
 
In the Left MFD, click '''PG''', '''BV''', and '''AB'''.
 
[[Image:LOI.jpg|frame|left|IMFD setup for the LOI burn]]
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
When the burn is finished, LRO then completes 4 orbits at 3160km x 216km before the next burn.
 
you can switch focus to AV020Centaur and enjoy the view as it passes by the moon.
 
 
   
 
   
After the flyby, switch back to LRO and after 4 orbits, wait until ''PeT''
+
After the flyby, switch back to LRO and after 4 orbits, wait until PeT
is ''1k''. Press the '''retrograde''' button, and de-select it when retrograde attitude is achieved.  
+
is 800k. Press the retrograde button, and de-select it when retrograde attitude is achieved.  
 
  Follow the procedure above to make the second burn,
 
  Follow the procedure above to make the second burn,
  using initial values of ''TEj'' = '''600''' seconds from PeT, ''dVf'' = '''-194''',
+
  keeping PeA as close as possible to 216km, and burn until ApA is 967km.
and ''dVo'' = '''57.6''', keeping ''PeA'' as close as possible to ''216km'', and ''ApA'' at ''967km''.
 
the ''dVo'' parameter will affect ''PeA''.  
 
  
 
After another 5 complete orbits at 216km x 967km, make a third burn to circularize your orbit at 216km.
 
After another 5 complete orbits at 216km x 967km, make a third burn to circularize your orbit at 216km.
You will not be able to completely circularize the burn with IMFD course, so you can use IMFD orbital mode
 
for a final touch up.
 
  
 
Make a final burn on your next pass over the North Pole to reduce your PeA to 30km near the South Pole.
 
Make a final burn on your next pass over the North Pole to reduce your PeA to 30km near the South Pole.
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=== LRO Orbit Circularization ===
 
=== LRO Orbit Circularization ===
 
60 days after your last LRO orbit insertion burn,
 
60 days after your last LRO orbit insertion burn,
switch focus to LRO, and at Perilune over the south pole, burn retrograde until the ApA is 70km.
+
switch focus to LRO, and at Perilune over the south pole, burn retrograde until the ApA is 50km.
  
=== LCROSS Lunar pole targeting ===
+
=== LCROSS Lunar pole targetinjg ===
 
Switch focus back to AV020Centaur. When the PeT is 130k Set IMFD map in the left MFD and IMFD Base approach in the right MFD.
 
Switch focus back to AV020Centaur. When the PeT is 130k Set IMFD map in the left MFD and IMFD Base approach in the right MFD.
 
  In the left MFD set target Moon and center to Self ('''x''')
 
  In the left MFD set target Moon and center to Self ('''x''')
 
  Click on '''Sel''' until ''Ref Moon'' is displayed with a negative PeA.
 
  Click on '''Sel''' until ''Ref Moon'' is displayed with a negative PeA.
 
  In the right MFD click '''REF''', and type '''Moon'''.  
 
  In the right MFD click '''REF''', and type '''Moon'''.  
  Click '''Nxt''' until ''Hint'' is highlighted. Click '''Set''' and type the value shown for ''PeT'' in the left MFD.
+
  Click '''Nxt''' until ''Hint'' is highlighted. Click '''Set''' and type the value shown for ''PeA'' in the left MFD.
 
  Click '''Prv''' until ''Lat'' is highlighted. Click '''Set''' and type '''89.9'''
 
  Click '''Prv''' until ''Lat'' is highlighted. Click '''Set''' and type '''89.9'''
 
  Click '''Nxt''', then '''Set''' and set the ''Alt'' to '''0'''.
 
  Click '''Nxt''', then '''Set''' and set the ''Alt'' to '''0'''.
  Click '''Nxt''', then '''Set''' and set the ''ReA'' (Re-enty Angle) to '''70'''
+
  Click '''Nxt''', then '''Set''' and set the ''ReA'' (Re-enty Angle) to '''75'''
 
  Click '''Nxt''', then '''Set''' and set the ''Ant'' parameter to '''0'''
 
  Click '''Nxt''', then '''Set''' and set the ''Ant'' parameter to '''0'''
 
  You may need to reset the ''Hint'' Parameter at this time to the current PeT.
 
  You may need to reset the ''Hint'' Parameter at this time to the current PeT.
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=== LCROSS LRO targeting ===
 
=== LCROSS LRO targeting ===
 +
* ~7 hours prior to impact, LCROSS will separate from Centaur upper stage and perform a ~4-minute delay maneuver (~23 m/s)  to enable LCROSS to fly through Centaur impact plume
 
  In the left MFD, click '''REF''' and type '''Moon''', then click '''TGT''' and type '''LRO'''
 
  In the left MFD, click '''REF''' and type '''Moon''', then click '''TGT''' and type '''LRO'''
 
  Click '''PRJ''' until ''Target'' is displayed in the lower left corner.
 
  Click '''PRJ''' until ''Target'' is displayed in the lower left corner.
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=== LCROSS Separation ===
 
=== LCROSS Separation ===
* ~7 hours prior to impact, LCROSS will separate from Centaur upper stage and perform a ~4-minute delay maneuver (~23 m/s)  to enable LCROSS to fly through Centaur impact plume
 
 
Wait until Pet in the Left MFD is 25k.  
 
Wait until Pet in the Left MFD is 25k.  
 
  In the right MFD, minimize ''dV'' by adjusting ''ReA'', and make the burn.
 
  In the right MFD, minimize ''dV'' by adjusting ''ReA'', and make the burn.
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[http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20080038058_2008037121.pdf LRO Navigation Overview]
 
[http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20080038058_2008037121.pdf LRO Navigation Overview]
  
== Copyrights and Disclaimers ==
+
== TODO ==
*LRO/LCROSS Orbiter Add-On Copyright 2008 Brian Jones
+
*Fix procedure for actual mission parameters
*LRO/LCROSS Documentation Copyright 2008 Brian Jones and Chris Coffin
+
** updated Launch date? - currently: 2nd March 2009 05:26:27
*Commercial redistribution prohibited.
+
** LCROSS North pole impact
*Permission granted for use to NASA GSFC and ASU LROC
+
*** Target a specific crater
*Permission granted for Educational and personal use.
+
** Try IMFD slingshot mode to refine flyby once in lunar SOI
*Not for Navigational purposes. No warranty, express or implied.
+
* Add keyboard commands section
*Not liable for any damages arising from use of this software or documentation.
+
* Convert to .CHM for help mode within orbiter
 
+
* Add images
==See also==
+
** IMFD map periapsis projection to show LCROSS orbit inclination
[[Lunar Reconnaissance Orbiter]]
 
 
 
[[Category:Articles]]
 
[[Category:Add-ons]]
 
[[Category:Spacecraft add-ons]]
 
[[Category: Add-ons by BrianJ]]
 
[[Category:Tutorials]]
 

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