Deicing boots are commonly found on commercial jets. Commercial jets fly at high altitudes. The typical cruising altitude for a commercial jet is about 30,000 to 40,000 feet. At these altitudes, temperatures can drop to a staggering minus 70 degrees Fahrenheit.

Moisture, of course, freezes at just 32 degrees Fahrenheit. To prevent ice from building up on their wings and control surfaces, commercial jets are equipped with deicing boots.

What Are Deicing Boots?

Deicing boots are inflatable rubber membranes. They are typically found on the wings of commercial jets as well as the horizontal and vertical stabilizers. Deicing boots live up to their namesake by “deicing” these surfaces. They won’t necessarily prevent ice from forming. Rather, deicing boots are designed to remove ice from wings and stabilizers.

How Deicing Boots Work

As ice begins to form on the wings or control surfaces of a commercial jet, the deicing boots will inflate with the air. There are different types of deicing boots, but most of them use a pneumatic method of operation. They will inflate with air to remove ice.

Deicing boots consist of hollow pieces of rubber. By default, they aren’t inflated. They only inflate when ice begins to form on the wings or control surfaces where they are installed. Pumping air into the deicing boots forces them to expand. The deicing boots will become bigger while subsequently cracking and knocking off any ice from the wings or control surfaces.

Alternatives to Deicing Boots

There are other ways to deal with ice on the wings and control surfaces of airplanes. Rather than using deicing boots, for instance, some airplanes use heating systems. Bleed-air heating systems are a popular alternative to deicing boots. They work by bleeding hot air off the engine and redirecting it towards the wings and control surfaces.

Other airplanes use an electrical heating system. Electrical heating systems leverage a network of wires on the wings and control surfaces. Electricity will travel through these wires to heat them up. And as the wires heat up, so will the wings and control surfaces.

It’s important to note that deicing boots aren’t immune to failure. They can develop holes or tears that render them inoperable. If a deicing boot is punctured, it won’t be able to hold air. Therefore, the deicing boot won’t expand when air is pumped into it, nor will the deicing boot remove ice.