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 batteries in the LM than would otherwise be required, so the LM will remain inactive for most of the translunar phase. The operations during the docked period prior to separation will require about 20 minutes and will, of course, necessitate one of the crewmen leaving his couch and moving to the area of the docking tunnel. There is less inherent radiation protection from equipment and storage in the tunnel area for the crew; however, these operations do not require the crewman to be in this area for very long, and, further, this period coincides with the pas­ sage between the inner and outer radiation belts where the radiation level is lowest. Hence, there are no radiation constraints as a result of this operation.

A schematic representation of the docking indexing is shown in Figure 29. The CSM-LM axes are offset by 60°. This allows the CM pilot to line up on the docking target located on the LM. Similarly, when docking in lunar oribt, this indexing will allow the LM pilot to see the docking target mounted in the CM right hand window. Also shown in the diagram is the CSM high gain antenna which, unless the pitch attitude is properly selected, will be shrouded by the adapter panels. The S-IVB high gain antenna is located in this same quadrant (along the -Z axis of LM).

After completion of hard docking, the LM attachment ties are severed, and the LM is extracted from the adapter using the SM RCS system to bake away (Figure 30). Approximately 3 ft/sec. separation velocity is applied by the RCS which is sufficiently high to vir­tually assure no problem of subsequent recontact with the S-IVB.

It would be well here to point out a general characteristic of the Apollo spacecraft - namely, its large radius of gyration in pitch and yaw, its small value in roll. This being the lunar vehicle, it is not close coupled as Mercury and Gemini, except in roll.

One deg/sec. rate costs 11 lbs. in pitch and yaw and 1 lb. in roll (to start and stop). The 5°/sec rate referred to earlier, then, cost about 50 lbs. This is a large price to pay for that simple maneuver, but experience indicates that long periods remote from the station-keeping target should be avoided. It is illustra­tive of the cost per maneuver. This cost leads to pre-planned maneuvers to take advantage of the low inertia in roll and to think through each maneuver to minimize propellant consumption. This frugal use of RCS reactant is mandatory until the possible requirement for LM rescue in lunar orbit has passed.