FAA Aviation Mechanic Airframe (AMA)Fuel, Cabin and Ice Control SystemsMedium
On a turbine-powered transport aircraft, the wing leading edge anti-ice system uses hot air routed through small perforated tubes running the length of the wing. What is the source of this hot air?
- AElectric resistance heating elements
- BRam air heated by compression in the pitot system
- CExhaust gas tapped directly from the turbine tailpipe
- DEngine bleed air ducted through a piccolo tube
Show answer & explanationAnswer & explanation
Correct answer: D. Engine bleed air ducted through a piccolo tube
Most transport category turbine aircraft use hot engine bleed air routed through a perforated piccolo tube inside the wing leading edge to continuously anti-ice the surface by heating it from within.
Why the other options are wrong
- A. Electric heating elements are more typical of small probes, propellers, or empennage anti-ice, not large wing leading edges.
- B. Ram air heating is not used for wing anti-ice; pitot heat is electric.
- C. Raw exhaust gas is far too hot and is never ducted directly for anti-ice use.
Piccolo Tube Wing Anti-Ice
A perforated tube running inside a wing leading edge that distributes hot engine bleed air along its length to prevent ice formation.
- Uses engine bleed air, not electric heat
- Perforations spray hot air against the inner leading edge skin
- Common on transport category turbine aircraft
Memory trick: Piccolo tube plays a tune of hot air along the wing.