A lightweight balloon sent into the atmosphere ahead of a primary flight to gather real-time meteorological data. Ground crews track its ascent visually or via radar to determine wind speed, direction, and shear layers at various altitudes. This data helps pilots of larger balloons or experimental aircraft plan their flight profiles and anticipate hazardous weather conditions.
Heard on the job
Release the trial balloon and track its drift so we know what the winds aloft are doing before we inflate the main envelope.
Also heard as
- pilot balloon
- pibal