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2 Typical Mission Profile This document guides you through a typical Lunar exploration mission. Training missions are included to help you gain experience before you attempt to land on the Moon. Topics include: Mission Planning Landing on the Lunar Surface Abort Procedure EVA Activities Return to the LOL Emergency EVA Training Missions Mission Planning Mission planning includes selecting the landing site, planning EVA routes and activities, and planning orbital maneuvers. Select a Landing Site: Possible missions include visiting previous Apollo, Surveyor, or Luna landing sites, unusual geological features, etc. Map the vicinity of the primary target using MAPGEN at level 1. Select a smooth cell near the primary target as the landing site. Enter the coordinates of the landing site into NEWGAME. Plan EVA Routes and Activities: Choose EVA routes that minimize the distance traveled over rough areas. EVA activities may include sampling high-value geological formations or manmade objects. Plan Orbital Maneuvers: Note the sequence, timing, and duration of RCS and main engine burns. Landing on the Lunar Surface Landing includes transferring to and checking out the LM, undocking and separating from the LOL, performing two plane change maneuvers, putting the LM into a descent orbit, beginning powered descent, and landing on the Moon. Transfer/Checkout of LM: Set the INS display to "POS-TAR". Begin transfer to and checkout of the LM about 60° west of the landing site. Transfer and checkout of the LM reqires about 45 min to complete. Undocking/Separation from LOL: [Place the LM into an orbit that returns it to the vicinity of the LOL in about 2 hr if no further action is taken.] Set the INS display to "POS-TAR" and the RCS throttle to "LOW". UNDOCK after LM checkout, 155° east of the landing site. Undocking defines MET 00:00 and imparts a small northward velocity (≈0.1 m/s) to the LM. Set the INS display to "POS-REL". At 50 m from the LOL, use the RCS DOWN thruster to increase the separation velocity to 0.3 m/s. Set the RCS throttle to "MEDIUM" and ROLL the LM so the Face body axis points up. Set the INS display to "POS-TAR". At 105° east of the landing site, use the RCS FACE thruster to increase the LM upward velocity by 1 m/s. Turn ON the DSN transponder. Landing on the Lunar Surface (continued) Plane Change Maneuvers: [Modify the LM orbit to pass directly over the landing site.] Set the INS display to "POS-TAR" and the RCS throttle to "MEDIUM". At 3° east of the landing site, about MET 00:45, use the RCS UP or DOWN thruster to cancel the north/south velocity component. Next, orient the LM so the Face body axis points up and the Up body axis points toward the pole of the hemisphere not containing the landing site. At 87° west of the landing site, about MET 01:15, set the INS display to "ORB-TAR". If the landing site is in the southern hemisphere, use the Descent Engine to change the angular momentum "NORTH" component to 90°. Otherwise, change it to (90-2·L)°, where "L" is the landing site latitude. During the burn, YAW the LM so the direction of thrust remains perpendicular to the orbit plane. Descent Orbit Insertion (DOI): [Change the LM orbit from 100km circular to 20 km by 100 km with a perilune about 15° east of the landing site.] Set the INS display to "POS-TAR" and the RCS throttle to "MEDIUM". Orient the LM so the Face body axis points up and the Left Body axis points south. When the LM is 165° west of the landing site, about MET 01:40, IGNITE the Descent Engine and switch the INS display to "ORB-TAR". Continue the burn for about 50 s until the perilune is slightly greater than 20 km. After Descent Engine cutoff, use the RCS UP thruster to adjust the perilune to 20 km. Landing on the Lunar Surface (continued) Powered Descent Initiation (PDI): Set the INS display to "POS-TAR" and the RCS throttle to "HIGH". Orient the LM so the Face body axis points up and the Left Body axis points south. At 18° east of the landing site, about MET 02:40, start the Descent Autopilot. The LM will be guided automatically to a point near the landing site. Turn the Landing Radar ON at an altitude of 12 km and the DSN transponder OFF at 6 km. During descent, use the RCS LEFT and RIGHT thrusters or YAW control to adjust the crosstrack position and velocity. Resume manual control at an altitude of 1000 m. Final Approach and Landing: Reduce horizontal velocity components to less than 1 m/s while gradually bringing the LM to an upright position. Use RCS thrusters to cancel the horizontal velocity when the LM is directly over a smooth lurrain area. Set the RCS throttle to "MEDIUM". Use the Descent Engine throttle to control the rate of descent. At 200 m, the Landing Radar display is activated. Land, if possible, with horizontal and vertical velocity components less than 0.3 m/s and 1 m/s, respectively. A successful landing is indicated by the "TOUCHDOWN" light. REST immediately after landing in preparation for the first EVA. Abort Procedure Start the Abort sequencer if trouble occurs during final approach and landing, e.g., the LM runs low on propellant or the rate of descent is too rapid. The Abort sequencer stops all rotational motion, turns off all RCS translation thrusters, shuts down the Descent Engine, jettisons the Descent Stage, and ignites the Ascent Engine. During ascent, the LM is under manual control. Immediately PITCH forward rapidly until the LM Up body axis is pointing up. Continue to pitch forward at 1°/s until reaching a "u/r" angle of 60°, heading west. ROLL rapidly at 5°/s by 180° until the LM Left body axis points north. Turn OFF the Landing Radar and turn ON the DSN transponder. Use the PITCH control to bring the LM to an altitude of 20 km with a perilune of slightly less than 20 km. This orbit may roughly be achieved by pitching back 5° every 40 s during the remainder of the burn. Turn OFF the Ascent Engine after achieving the proper orbit. Use the RCS UP thruster to put the LM into a 20 km circular orbit. Rendezvous, approach, and dock with the LOL following standard procedures. EVA Activities EVA activities include preparing for EVA, leaving the LM, operating the LRV, collecting samples, transferring sample boxes from the LRV to the LM, reentering the LM, and terminating the EVA. The first EVA begins after a rest period following landing. Subsequent EVAs occur following sleep and rest/meal periods on successive days while on the Lunar surface. Preparation and LM Egress: A rest/meal period is recommended following landing or a sleep period prior to beginning EVA preparation. Put on the spacesuit and PLSS, evacuate the cabin, and exit the LM. Preparation and egress requires about 1.5 hr to complete. LRV Operation: Set the INS display to "POS-ABS". Enter the LRV and drive to the first sample collection location as defined during mission planning. Set the LRV throttle to 50-60% while driving over open lurrain. When approaching rough terrain, reduce throttle to 20-30%. Avoid very rough spots, the LM, and manmade objects. Park the LRV between 20 m and 40 m of the sampling location. Make sure the LRV is completely stopped by decreasing the throttle several times. EVA Activities (continued) Sample Collection: Exit the LRV and move to the cell containing the sampling site. Collect samples and put them into the LRV sample box. The EVA score is incremented as samples are collected, with higher value samples resulting in higher scores. When finished, enter the LRV and drive to the next site. Make sure the PLSS is completely stopped by decreasing the throttle several times. Sample Box Transfer to the LM: When all sampling sites have been visited or the LRV sample box is full, set the INS display to "POS-REL" and return to the LM. Pick up the box from the LRV and transfer it to the LM. The EVA score is incremented, depending on the total amount of sample collected, and displayed. Additional boxes may be used if sufficient time remains. EVAs should be completed between UT 16:30 and 18:30. LM Ingress and Termination: Reenter the LM at the end of an EVA, pressurize the cabin, and remove the PLSS and spacesuit. Ingress and termination require about 1.5 hr to complete. REST once or twice in preparation for the next sleep period. SLEEP in preparation for the next EVA or liftoff. For maximum efficiency, begin sleep periods about UT 22:00. Return to the LOL Returning to the LOL includes lifting off from the Lunar surface, adjusting the initial orbit, performing transfer orbit, plane change, and circularization burns, and approaching, docking, and transferring to the LOL. Liftoff and Initial Orbital Adjustment: [Put the LM into a 20 km circular orbit.] Begin liftoff after sleep and rest/meal periods, between UT 09:00 and 11:00. Set the INS display to "POS-REL" and the RCS throttle to "HIGH". Start the Ascent Autopilot when the LOL is 5° east of the landing site. The LM will automatically liftoff from the Lunar surface and be placed into an orbit with an apolune of about 20 km. Immediately after liftoff, switch the INS display to "POS-TAR" and turn ON the DSN transponder. During ascent, use the PITCH control if necessary to adjust the rate of ascent. Increase the burn time, as required, if the LM is carrying a large quantity of Lunar samples. After Ascent Engine cutoff, set the INS display to "ORB-ABS" and use the RCS UP thruster to raise the perilune to 20 km. Transfer Orbit Maneuver: [Put the LM in a 20 km by 100 km orbit that brings it near to the LOL.] Orient the LM so the Face body axis points up and the Left body axis points north. Set the INS display to "POS-REL" and the RCS throttle to "MEDIUM". When the LM is 5.8° east of the LOL, about 15 min after liftoff, switch the INS display to "ORB-ABS", and use the Ascent Engine to Return to the LOL (continued) raise the apolune to slightly less than 100 km. The transfer orbit burn lasts about 3 s. Use the RCS UP thruster to raise the apolune to 100 km. Plane Change Maneuver: [Put the LM into an equatorial orbit.] Set the INS display to "POS-ABS" and the RCS throttle to "HIGH". Orient the LM so the Up body axis points toward the pole of the hemisphere containing the landing site. As the LM crosses the Lunar equator, about 30 min after liftoff, use the Ascent Engine and RCS to set the north component of velocity to 1 m/s. During the burn, YAW the LM so the direction of thrust remains perpendicular to the orbit plane. Circularization Burn: [Put the LM into a 100 km circular orbit.] Set the INS display to "POS-REL" and the RCS throttle to "MEDIUM". Orient the LM so the Face body axis points up and the Left body axis points north. As the LM passes near the LOL, turn ON the LOL transponder. Turn it OFF before the circularization burn. Near apolune, when the LM is at least 1 km east of the LOL, about 1 hr after liftoff, IGNITE the Ascent Engine and raise the perilune to about 100 km by burning for 3 s. The LM should be within 10 km of the LOL. Turn ON the LOL transponder and turn OFF the DSN transponder. The LOL transponder must be ON to dock. Return to the LOL (continued) LOL Approach: [Bring the LM to within 500 m north of the LOL.] Set the INS display to "POS-REL" and the RCS throttle to "MEDIUM". Orient the LM so the Face body axis points up and the Up body axis points south. Use the RCS translation thrusters to bring the LM to a point approximately 500m north of the LOL. LOL Docking and Transfer: Set the RCS throttle to "LOW" and orient the LM so the Face body axis points up and the Up body axis points south. Use the RCS translation thrusters to precisely align the LM with the LOL both in altitude and east/west. Approach the LOL at about 0.5 m/s. At 200 m, the Docking Radar display is activated. Slow the approach velocity to 0.3 m/s. Align the LM to center the "ROLL" alignment indicator by executing a clockwise or counterclockwise ROLL command if the alignment indicator is to the left or right of the display, respectively. If necessary, align the LM to center the "PITCH/YAW" alignment indicator. Use the RCS thrusters during final approach to keep the LM position aligned with the center of the docking port. Dock, if possible, with an approach velocity between 0.2 and 0.4 m/s. A successful docking is indicated by the "DOCKING" light. If a docking attempt fails, the LM bounces off the LOL and the final approach must be repeated. After successfully docking, transfer to the LOL to complete the mission. Emergency EVA The LM and/or LOL may become damaged such that docking is no longer possible. If LM and LOL damage become severe (50% or more), the Pilot must transfer to the LOL using an emergency EVA. At a safe distance from the LOL, put on the spacesuit and evacuate the cabin. Set the INS display to "POS-REL" and the RCS throttle to "LOW". Move the LM to about 80 m east or west of the LOL and reduce the relative velocity as low as possible. Execute a "MOVE" command to transfer to the LOL and complete the mission. Training Missions Training missions are suggested, in increasing order of difficulty, that allow you to become familiar with flying the LM. Try at least one of each variety before proceeding to the next level of difficulty. Mission #1: Transfer to and checkout the LM. UNDOCK and perform the first separation burn. Turn ON the LOL transponder. Practice using the PITCH, ROLL, and YAW controls and RCS thrusters. After about 1 hr, approach and dock with the LOL. This mission requires about 2.5 hr to complete. Mission #2: Same as #1 but add the second separation burn. After one orbit, approach and dock with the LOL. Use the LOL transponder while the LM is within 30 km of the LOL, otherwise use the DSN transponder. This mission requires about 4.5 hr to complete. Mission #3: Same as #2 but add the two plane change maneuvers so the LM overflies the landing site. After one full orbit, put the LM into an equatorial orbit by cancelling the north/south component of velocity as it crosses the Lunar equator. After one-half orbit, approach and dock with the LOL. This mission requires about 6.5 hr to complete. Training Missions (continued) Mission #4: [This mission is similar to that of Apollo 10.] Same as #3 but add the DOI maneuver. After returning to the apolune of the descent orbit, put the LM into a 100 km by 180 km orbit to restore the relative position of the LM west of the LOL. After another orbit, circularize the LM orbit. Put the LM into an equatorial orbit, approach, and dock with the LOL. This mission requires about 8.5 hr to complete. Other Missions: You are now ready to attempt a landing. Start with targets located near the Lunar equator. As you gain experience, try to explore more challenging targets at higher and higher latitudes. To practice parts of missions, you can copy one of the tutorial save files "*.SAV" to "AMS.SAV" and start the AMS. HAPPY LANDINGS !