Definition
Pitot tubes fitted with an internal electrical heating element that prevents ice from forming over or inside the tube's ram-air opening, preserving accurate airspeed indication when flying in visible moisture at or below freezing temperatures.
Plain English
The small forward-facing tube that feeds the airspeed indicator can ice over in cold, wet conditions and stop working. A heated pitot tube has a built-in heater the pilot switches on to keep it clear so the airspeed reading stays correct.
Context Anchor
You encounter heated pitot tubes during preflight inspection, cockpit system checks, and anti-icing or deicing discussions, especially before flight in cold visible moisture.
Derivation
Named after Henri Pitot, the French engineer who in the 1700s devised the tube used to measure fluid speed. 'Heated' is added because the tube includes an electrical element to keep it ice-free.
Why Pilots Care
Ice-blocked pitot tubes can cause dangerously misleading airspeed information, potentially leading to loss of control; the heating system ensures reliable data for safe flight.
Analogy
It is like using a heated windshield line to keep a small opening from freezing shut. The heat is not there to change what the system measures; it is there to keep the opening usable.
Intuition Check
Do not read heated as meaning the tube warms the air for comfort or engine use. Here, heated means electrically warmed to help prevent ice from blocking the air pressure opening.
Example Sentence 1
Before climbing into the clouds with an outside air temperature near freezing, the pilot turned on the pitot heat to keep the heated pitot tube clear of ice.
Example Sentence 2
During the preflight, the instructor demonstrated how to check that the heated pitot tubes were drawing the correct amount of electrical current.