Figure 2.2—Intercom (left) and CDU panel (right).
If the GPS is working, then the launch is a GO. Refer to Chapter 6, Section D for GPS failure prior to launch.
Grab the balloon and unhook it. Walk about 20-30 feet outside of the building to release the balloon. If winds are light, the balloon will travel generally straight up. In this case, carry the balloon a greater distance away from the inflation shelter before releasing. There must be enough clearance to prevent the balloon from hitting the building (bursting the balloon) and for the sonde from hitting the building (damages the sensors).
Before release make sure that the area is clear of low-flying aircraft, especially if the station is located near an airport. If necessary or required, call the air traffic control tower to request launch clearance. This may be required for launch sites near high traffic airports.
Either pick up and hold the sonde before releasing the balloon, or be in a position to quickly grab the sonde after balloon release. DO NOT LET THE BALLOON CARRY THE SONDE OUT OF THE BUCKET. This could cause damage to the instrument.