Definition

Noun: A small, unmanned balloon, typically filled with helium or hydrogen, that is released into the atmosphere to be tracked visually or by radar. Its ascent and drift are observed to determine the speed and direction of wind currents at various altitudes, providing data for meteorological observations and forecasts.

Usage Examples

• The weather station releases a pilot balloon every six hours to measure upper-level winds.
• By tracking the pilot balloon with a theodolite, meteorologists calculated the wind velocity.
• Before the flight, the crew checked the data obtained from the latest pilot balloon.

Advanced Usage

• "to track a pilot balloon": To follow the ascent and movement of a pilot balloon using an optical or electronic instrument to gather wind data.
  • The technician tracked the pilot balloon until it disappeared into the clouds.

Variants and Related Words

• Sounding balloon: A type of balloon that carries instruments to measure atmospheric parameters, often larger and more complex than a simple pilot balloon.
• Weather balloon: A broader term that can encompass pilot balloons as well as balloons carrying instrument packages (radiosondes).

Synonyms

• Meteorological balloon (in the specific context of wind observation)
• Wind-finding balloon

Related Terms and Phrases

• Radiosonde: An instrument package carried aloft by a balloon to transmit meteorological data, often contrasted with a simple, instrument-free pilot balloon used primarily for wind tracking.
• Theodolite: An optical instrument used for tracking pilot balloons to measure angles and calculate wind speed and direction.

Noun

1. meteorological balloon used to observe air currents