Lunar Reconnaissance Orbiter part 2

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
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 216k 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

In the right MFD, click ++ to turn Maneuvre mode On.
Adjust Prograde vel and Ch. plane vel so that on the Left MFD R. Inc is as close as possible to 0,
and Pe Ratio is as close as possible to 1.0
Click VW on the right MFD for Target view. Use rotational thrusters to get the cross as close to the
center of the target as possible. Press M to enable the dummy main engine, and use the numpad-+ key to
burn the engine. Reduce the Rel V to as close to 0 as possible. 

As an alternative to using the dummy main engine, after the Centaur is targeted with rotational thrusters, you can 
rotate the Centaur 180 degrees and use the LCROSS main engine numpad-- (minus) This will provide you with graphics
of the engine firing in external view. (F1)

Repeat these adjustments as necessary as you get closer to the moon.

orbit insertion/LRO

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 10k, select IMFD in the left MFD, and Orbit MFD in the right.

Click on the HUD button on the right MFD. In the left MFD click MNU, then Orbital.
Click TgT, then type r.

Note that The burn time to a circular orbit is over 4k seconds (over an hour!). Make sure rotational mode is selected.

At 2k seconds to PeT, select Retrograde mode on the hud. When retrograde attitude is established, de-select retrograde mode.
Start the engine by pressing numpad-+ and tap the CTRL key to keep it burning.

Notice that the PeA in the right MFD is decreasing.

Use the numpad 1 and 3 keys to move the attitude closer to what the Orbital IMFD mode thinks it should be until
the PeA starts increasing. 

Keep adjusting the attitude between these points to keep the PeA as close as possible to 216km.

When the ApA. parameter in the Right MFD is 3160km, press the numpad-* key to stop the burn.
The 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 is 800k. Press the retrograde button, and de-select it when retrograde attitude is achieved.

Follow the procedure above to make the second burn,
keeping PeA as close as possible to 216km, and burn until ApA is 967km.

After another 5 complete orbits at 216km x 967km, make a third burn to circularize your orbit at 216km.

Make a final burn on your next pass over the North Pole to reduce your PeA to 30km near the South Pole.

This is the "frozen" lunar orbit at 216km x 30km, periselene over the South Pole, for the 60-day commissioning phase.

LCROSS orbit correction 1

Switch focus back to AV020Centaur and wait until the orbit is farthest from the moon. WARNING Using High values of time acceleration may cause problems for the LRO orbit. It can even kick it out of lunar orbit. It is best to be patient, and check on LRO's orbit once in a while. If it's orbit changes significantly due to time acceleration, fix it with scenario editor. It is now necessary to tune IMFD map for maximum accuracy.

Select IMFD in the left MFD. Click MNU, then Map. Click TgT and type Moon, Click Cnt, and type Earth.
Click MOD 3 times. This should give you the Map-config screen. Legs/Frame should be highlighted. Click Set and type 64.
Click Nxt, then - twice. Click Nxt twice again, so that Period limit is highlighted, and click + to turn it off.
Click Nxt and + to turn Hyper limit off. Click Nxt twice and then + so that Tgt weak Pe is set to No.
Click Nxt and + to turn One Pe/Ref off. Click Mod again to return to the map display. 

Several orbits should now be shown. Select IMFD in the Right MFD.

In the right MFD click MNU, then Course. Select Delta Velocity mode, then set the target to Moon. Set the dVf parameter to 0.
In the left MFD click PG, then Plan. in the right MFD, adjust dVf to get the most deflection of the orbit you can when 
LCROSS intersects the moon in 1.5 orbits. When this is done, click on Pg, then BV, then AB.
When the burn is finished, click Plan in the left MFD to turn the orbit line green again.

Alternate procedure

Select transx in the right MFD.

In the right MFD, select target moon and 1.5 orbits to intercept. Change the view to Maneuver, and select Maneuver mode.
Adjust prograde vel, and Ch. Pl vel for the minimum closest approach. 
Select target view and use rotational mode to align the cross with the target. 
Start the burn and watch the orbit in Map MFD mode in the left MFD. When maximum orbit deflection is reached at the moon intercept point
after 1.5 orbits, stop the burn.

LCROSS final moon targeting

Go around one more orbit of the earth. When we are again at the farthest point in our orbit from the lunar intercept, set IMFD map in the left MFD and IMFD course in the right MFD.

In the right MFD set target intercept mode. Set target to Moon.
Adjust the TIn MJD and then TIn parameters for minimum Enroute dV. Change Target intercept mode to Delta Velocity mode.
Click Nxt 4 times to highlight Get Burn, and click +.
In the left MFD click Sel until ref is Moon and PeA is the lowest value. Click Pg, then Plan.
In the right MFD adjust the highest value of dVf, dVp, or dVo to minimise PeA in the left MFD.
As the orbit changes, the PeA number may change, so you may have to return to the proper one with the Sel button once in a while
Adjust the next highest value of dVf, dVp, or dVo, and finally adjust remaining value. 
When these adjustments are done, click Pg, BV, and AB.

Note the PeT in the left MFD. We need to make another burn when we are halfway from here to the noon so that we will impact the moon. This will be at about 850k PeT. Repeat the above procedure until PeA is at least -1M, and hopefully as low as you can get it.

LRO Orbit Circularization

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 50km.

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.

In the left MFD set target Moon and center to Self (x)
Click on Sel until Ref Moon is displayed with a negative PeA.
In the right MFD click REF, and type Moon. 
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 Nxt', then Set and set the Alt to 0.
Click Nxt, then Set and set the ReA (Re-enty Angle) to 75
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 also need to tweak the Lon parameter to get the Enroute: dV parameter to display.
Once it is displayed, adjust the ReA parameter to minimize the dV. 
It may take several iterations of adjusting hint, Lon, and ReA to get the dV to a minimum value.
When a minimum dV value has been reached, click PG, BV, and AB.

Repeat the above procedure at Pet of 100k, again at 70k, and once more at 51k PeT.

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
Click PRJ until Target is displayed in the lower left corner.
Click Z- until you can see the white dot that represents the current vessel. Remember where this "incoming" leg of the orbit is located.
In the right MFD click MNU, then Course. Highlight Target Intercept, then click Set.
Click TGT, and type LRO. Click PRJ until LRO is shown in the lower left corner of the MFD.

The orientation of the two MFD's should now be exacly alike with repect to the position of the LCROSS and LRO orbits. We want to adjust the time of intercept of the LRO orbit so that it is 4 minutes (240 seconds) before LRO passes by.

In the right MFD click Nxt until the Tin parameter is highlighted.
Click + or - until the white intercept point line intersects the point where the incoming side of the LCROSS orbit intersects the LRO's orbit.  
Whether you use + or - depends on which has the least dV at the intersect point.
Click PG, then BV, then AB.

Once this burn is done we must turn prograde with respect to the orbit of the moon and burn an additional 5 m/s.

Make sure the HUD reference is ORBIT [Moon]. Use rotational thrusters to align in the prograde direction. 
Do not use the prograde autopilot, as we are not in the moons SOI yet. In the right MFD note the Tot line in the dV applied section.
Add 5 to this number and burn until the Tot dV applied equals this number.
When this burn is complete, in the right MFD click MNU, then Base Approach. 
Highlight Hint and set it to the current Pet in the left MFD. Click Prv twice to highlight ReA.
Click + or - to minimize Enroute dV. Click Pg, BV, and AB.

LCROSS Separation

Wait until Pet in the Left MFD is 25k.

In the left MFD, minimize dV by adjusting ReA, and make the burn.
Jettison LCROSS by pressing k

Once LCROSS is jettisoned, switch focus to the LCROSS spacecraft.

• current strategy
  • target LRO
  • boost additional 5m/s prograde
  • retarget base approach
  • separation at 25k PeT
  • LCROSS target LRO intersection
  • LCROSS target base approach
  • rinse, repeat

External reference documents

LCROSS Astronomer Workshop
NASA LCROSS page
NASA LRO page
ASU LRO Camera Page
Trajectory Design of the Lunar Impactor Mission Concept
Lunar Reconnaissance Orbiter Spacecraft & Objectives
Mission Design And Operations Considerations For NASA’S LRO
Mission Design for the Lunar Reconnaissance Orbiter

TODO

• Fix procedure for actual mission parameters
  • updated Launch date? - currently: 2nd March 2009 05:26:27
  • LCROSS North pole impact
    • Target a specific crater
  • Try IMFD slingshot mode to refine flyby once in lunar SOI
• Add keyboard commands section
• Convert to .CHM for help mode within orbiter
• Add images
  • IMFD map periapsis projection to show LCROSS orbit inclination