Mission Control Center

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The Mission Control Center function of Project Apollo – NASSP provides both Mission Tracking and Ground Tracking. Mission Tracking automatically uploads Pre-Advisory Data and state vectors that were handled by Mission Control during an Apollo Mission. When the MCC function is enabled it will uplink burn data and state vectors, as well as read up any PAD that is pertinent to upcoming maneuvers at historical points in the mission’s Flight Plan. The MCC is currently functional for both Apollo 7 and 8. It will not provide any calculations for abnormal conditions or flight plans. MCC also uses the Ground Tracking function to determine whether or not the spacecraft is in range of the various ground stations that make up the Manned Space Flight Network. When Ground Tracking is enabled the CAPCOM will call out when various stations have Acquision of Signal (AOS) or Loss of Signal (LOS) based on the spacecraft’s ground track and whether or not it is on the far side of the moon. Currently LOS does not prevent uplink from the Ground.


The user can interact with MCC through the CAPCOM menu on the upper left hand corner of the screen. The TAB key displays or hides the CAPCOM menu. When the CAPCOM menu is displayed the keyboard number keys select the corresponding menu option. The debug menu can enable or disable Ground Tracking and Mission Tracking. Pressing [TAB] [9] [2] will change the enabled status of Mission Tracking and display that status in text on the top of the screen. Mission and Ground Tracking must be enabled before Liftoff in order to properly track the progress of the mission. When active, the CAPCOM will make various launch callouts along the top of the screen. When the ground has PAD data to be copied, MCC sets time acceleration to 1x and will inform the crew of the new PAD. If PAD Auto-show is enabled by pressing [TAB] [4], the PAD will be immediately displayed along the left hand side of the screen. The PAD can be hidden or shown by pressing [TAB] [5], “Hide/Show PAD.” When the ground has a statevector or burn data to uplink, time acceleration is set to 1x and the crew will be notified with the message “Ready for uplink?” [TAB] [2] “Ready for uplink” informs the ground the DSKY is in Program 00 and the UPLNK TLM switch is set to accept (referred to as going to P00H and accept). MCC currently does not check for “P00H and Accept” before proceeding with the uplink. The CAPCOM will inform the spacecraft of the uplink’s contents and when it has both begun and completed. If the CMC was not properly configured, [TAB] [3] will repeat the process.

Option Function
1 – Voice Check Performs voice check with the ground
2 – Ready for uplink Informs MCC to proceed with the uplink when in “P00H and Accept”
3 – Repeat uplink Informs MCC the spacecraft did not receive the uplink
4 – Toggle Auto PAD Toggles if the PAD will be automatically show when prepared
5 – Hide/Show PAD Hides or Shows the most recent PAD if available
6 – Redisplay Messages CAPCOM will repeat most recent messages

Pre-Advisory Data Terms

A PAD is Pre-Advisory Data. It consists of a number of fields of data which advise the crew on certain parameters of an upcoming maneuver. It typically includes items such as the time of different events (like ignition or 0.05g), burn attitudes, required delta-V, the expected orbit at the end of the maneuver, and various other data pertaining to the upcoming maneuver. The PAD is read up to the crew by the CAPCOM, and is read back by the crew to check for errors. Some PADs, like the P30 External Delta-V PAD, are paired with an uplink to load the data into the computer. Historically, the CAPCOM read up a series of numbers that would make sense when filled in on the PAD form. NASSP's CAPCOM displays the PAD data along the left hand side of the screen complete with labels and decimal points.

Below are the definitions of various PAD fields.

Field Definition Field Definition
Purpose Name of Maneuver BT Estimated Burntime (min, sec)
Prop/Guid Mode of Propulsion/Mode of Guidance SXTS Sxt Star Check #
GETI GET of Ignition (hrs, min, .01 sec) SFT Shaft Angle for Star Check
WT Weight of CSM/LM (lbs) TRN Trunnion Angle for Star Check
DVX (Y Z) Delta-V in X, Y, Z axis (.1 fps) LAT Latitude of Splashdown (.01 deg)
HA Height of Apogee at Cutoff (.1 nm) LONG Longitude of Splashdown (.01 deg)
HP Height of Perigee at Cutoff (.1 nm) ALT Altitude at Perigee (.1 nm)
DVC Delta-V for EMS Counter (.1 fps) RTGO Expected EI Distance of Travel (.1 nm)
DVT Total Delta V (.1 fps) V10 Expected Velocity at EI (fps)
PTRM Pitch TVC Trim Angle (.01 deg) GET .05g GET of .05g Event
YTRM Yaw TVC Trim Angle (.01 deg) R Roll (deg)
BSS Boresight Star # P(EVENT) Pitch of specified Event (deg)
SXP COAS Pitch Angle Y Yaw (deg)
SXA COAS X Angle TB6p Predicted Start of TB6 (hrs, min, .01 sec)
VI Intertial Velocity at Cutoff (.1 fps) GET HOR CK GET of Horizon Check
MAX G Maximum G Effects During EI (.01 G) V400K Velocity at EI (fps)
Y400K Flight Path Angle at EI (.01 deg) RRT Time of EI (hrs, min, sec)
RET 05g Time from EI to .05g (min, sec) D0 Entry Drag Level (.1 g)