Building 30: Mission Control Center (MCC)

Mission Control Center (MCC)

The MCC building had three wings: on the left side the Operations Wing, on the right side the Mission Support Wing (or Administration Wing) and a Lobby Wing in the center. The Operations Wing had two Mission Operations Control Rooms (MOCRs) on the second and third floor respectively. The elaborate systems for mission support: the Real Time Computer Complex (RTCC) and the Communication, Command And Telemetry Center (CCATS); were located on the first floor.

Credit to NASA.

MCC floor plans

MCC MCC Hotspots:
1. Purple area is linked to RTCC description
2. Brown area is linked to CCATS decription
MCC first floor
The elaborate systems for mission support: the Real Time Computer Complex (RTCC) and the Communication, Command And Telemetry Center (CCATS); were located on the first floor.

MOCR MOCR Hotspots:
1. Orange area is linked to SSR description
2. Red area is linked to MOCR description
MCC second floor
In red the Mssion Operations Control Room no. 1 (MOCR-1). That is the room where the flight controllers were residing. That crew was supported by an elaborate staff sitting in separate rooms, the Staff Support Rooms (SSRs), across the corridor on the same floor.

MOCR-1 has been mainly used for training and simulation.
However the following missions have been controlled from MOCR-1: Apollo 5, Apollo 7, the Skylab missions and the Apollo-Soyuz Test Project.


MOCR MOCR MOCR Hotspots:
1. Orange area is linked to SSR description
2. Red area is linked to MOCR description
3. Green area is linked to RCR description
MCC third floor
In red the Mssion Operations Control Room no. 2 (MOCR-2). That is the room where the flight controllers were residing. That crew was supported by an elaborate staff sitting in separate rooms, the Staff Support Rooms (SSRs), across the corridor on the same floor.

MOCR-2 was used as the primary room for flight control and mission management.
It has been used for the Gemini missions 4 to 12 and all the Apollo missions in which the Saturn V was used as the launch vehicle.
(The Gemini missions 1,2 and 3 were controlled from the Mercury Control Center at Cape Canaveral Missile Test Annex, Florida.)

On the same floor the Recovery Control Room (RCR) was located. This room arrangement bears some resemblance to MOCR. The crew of the RCR was in command in the last phase of the mission when the command module was reentring Earth's atmosphere and was on its way to its calculated landing area somewhere in the Pacific Ocean. There was a window between MOCR-2 and the RCR, it enabled the DOD officer, sitting at the top row in MOCR-2, to keep an eye on the activities in the RCR. DOD was responsible for the recovery activities.


The main systems of the Mission Control Center

CCATS RTCC MOCR MOCR SSR SSR RCR MSTF FCTB Hotspots:
1. RTCC part of diagram is linked to RTCC description
2. CCATS part of diagram is linked to CCATS decription
3. SSRs for training (green)
4. MOCR for training (green)
5. MOCR for mission support
6. RCR for mission support
7. SSRs for mission support

8. JSC MSTF, Mission Simulation and Training Facility
9. KSC FCTB, Flight Crew Training Building

Data flow and voice between the spacecraft and Mission Control

The Communication, Command and Telemetry System (CCATS) was the heart of a communication system between the spacecraft and the flight controllers. CCATS was connected to an elaborate world-wide network of tracking stations, stations to maintain data and voice communication with the spacecraft and communication relay satellites. CCATS had three UNIVAC 494 mainframe computers for data processing one as the Mission Operational Computer (MOC), a second as a Dynamic Standby (DSC) and a third UNIVAC 494 as a reserve available for other tasks.

The Real Time Computer Complex (RTCC) was used to transform data from CCATS into data suitable to display on the various console screens used by the flight controllers. The RTCC was also used to calculate and plot flight trajectories and to prepare data and commands to be uploaded to the spacecraft's on-board computer via CCATS. With five IBM 360 mainframes the RTCC had more computer redundancy than CCATS with its three UNIVACs 494.

In this diagram is shown how CCATS and RTCC could be configured in such a way that both centers can support an ongoing mission and support the training of flight controllers for the next mission at the same time. There were two Mission Operations Control Rooms (MOCRs) available to enable mission support and training simultaneously.

The UNIVAC 494's were used as communication processors and the IBM 360's as real-time data processors.

ASCATS
A system named ASCATS (Apollo Simulation Checkout And Training System) was used to simulate an Apollo mission.
The data generated by ASCATS to simulate data from launch vehicle, spacecraft and remote sites were indistinguishable from real mission data. With ASCATS data could be generated to simulate all kinds of malfunctions to train the crew, prepare them for various eventualities and to validate procedures. ASCATS could be configured in various ways for training the crew of the Mission Control Center, for training the astronauts and for training the crew at various remote sites. In a so called integrated simulation all groups were involved. ASCATS could be linked to a spacecraft trainer at JSC, building 5, or to a spacecraft trainer at KSC (Kennedy Space Center) in the FCTB (Flight Crew Training Building).

ASCATS was temporarily housed in building 422, as depited in the diagram, it had one UNIVAC 494, one IBM 360-75 and peripheral equipment. The UNIVAC 494 was used as the Apollo Process Control Unit (APCU) and the IBM 360-75 as the Ground Support Simulation Computer (GSSC).
The GSSC was able to generate data to act as a simulator for remote sites, for the spacecraft trainer, for MCC and for all three entities at the same time in an integrated simulation. ASCAT was controlled from the Apollo Simulation Control Area (ASCA). From ASCA faults could be inserted into the data streams to create simulated error conditions or simulated system malfunctions for training purposes.
ASCATS also contains a facility, Apollo Simulated Remote Site (ASRS), to train remote site personnel.

ASCATS was moved to the MCC in 1969. Its UNIVAC 494 and the IBM 360-75 computers were disposed of because one of the five computers of the RTCC and one of the three computers of the CCATS could be made available for training sessions.

GSFC
The Goddard Space Flight Center, in Greenbelt, Maryland, was the hub of the Manned Space Flight Network (MSFN), a worldwide network of tracking stations.


Acronyms
AGC Apollo Guidance Computer
APCU Apollo Process Control Unit
ASCA Apollo Simulation Control Area
ASCATS Apollo Simulation Checkout And Training System
ASRS Apollo Simulated Remote Site
CCATS Communication Command And Telemetry System
DSKY Display and keyboard
FCTB Flight Crew Training Building
FIDO Flight Dynamics Officer
GSSC Ground Support Simulation Computer
JSC Johnson Space Center (Houston, Texas)
KSC Kennedy Space Center (Florida)
MCC Mission Control Center
MOCR Mission Operations Control Room
MSFN Manned Space Flight Network
MSTF Mission Simulation and Training Facility
RCR Recovery Control Room
RETRO Retrofire Officer
RTCC Real-Time Computer Complex
SSR Staff Support Room

References
  1. Familiarization Manual
    Mission Control Center Houston
    PHO-FAM001, 30 June 1965
    by Western Development Laboratories, Houston Operations

  2. AS-508; MCC / MSFN; Mission Configuration / System Description
    March 1970
    by the Manned Spacecraft Center, Flight Support Division

  3. Mission Operational Configuration
    Mission J1, AS-510 / SC122 / LM10, Apollo 15
    PHO - TR155, 15 April 1971
    Manned Spacecraft Center, Houston




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Copyright 2020 by Sander Panhuyzen
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