Pull the train outside the building in the general direction the balloon will travel. Make sure the train will not get caught on anything after the balloon is released. If all is well, tie the end of the train to the plastic ring on the radiosonde. See Figure 2.1 for a diagram of the complete assembly.
Figure 2.1—Complete instrument assembly with balloon, parachute, train regulator, and radiosonde.
Proceed to the CDU panel and use the intercom to phone the Operations floor (Figure 2.2). Check that there is a proper GPS lock on the sonde. It may take 2-5 minutes after going to the inflation shelter for the satellites to get a good lock. There must be a MINIMUM OF 4 GPS MATCHES before the launch can proceed. There should also be all green checkmarks in the Hardware Status window. Be sure that the time is within the launch window (see Chapter 5, Section C). If within the launch window, the RWS software should show a message stating, “Waiting for Balloon Release."