Technical glossary

Water scooping operation – An operation in which an airtanker fills its tanks by skimming the surface of a body of water.

Wet Water – Water with added chemicals, called wetting agents, that increase spreading and penetrating properties of water by reducing its surface tension.

Wetting Agent – A chemical that reduces the surface tension of water causing it to spread and penetrate more effectively.

Wildfire – An unplanned or unwanted natural or human-caused fire, as contrasted with a prescribed fire. Note Forest Fire

Wye –

• without valves - A three-way hose line accessory permitting two lines of hose to be taken from a single supply line, with no provisions to regulate stream flow. Note Siamese without valves.
• with valves - A three-way hose line accessory permitting two lines of hose to be taken from a single supply line. Valves located in the discharge ports permit control of stream flow or shutting off one or both discharge lines. Note Siamese with valves.

  Note: If fitted with instantaneous twist-lock (unisex) couplings, a single accessory will perform the functions of both a wye and a siamese.