As winter months bring snowy landscapes and the Christmas holidays, they also pose a challenge for air travel: ice accumulation on aircraft surfaces.
Deicing is a crucial procedure during colder months, undertaken to ensure the safety and efficiency of air travel. This process involves removing ice, snow, and frost from the exterior surfaces of aircraft, as well as from airport runways and taxiways.
So, now let’s look at the various aspects of plane deicing and why it’s so critical in aviation.
What is deicing and why is it important?
Deicing is the process of removing or preventing the formation of ice on the external surfaces of an aircraft. Ice accumulation on areas like wings, tail and control surfaces can adversely affect the aircraft’s aerodynamics, leading to reduced lift and increased drag. This can compromise the overall performance and even safety of the flight.
There are two types of deicing methods for aircraft:
Ground deicing of an aircraft
Ground deicing typically takes place before the aircraft takes off. Specialized deicing trucks, equipped with large booms and nozzles, spray a heated glycol-based deicing fluid onto aircraft surfaces such as the fuselage, wings, and horizontal stabilizer. The heated fluid melts and removes ice and snow while creating a thin protective layer to prevent further accumulation during takeoff.
After deicing, ground crews may apply anti-icing fluid to the aircraft. This unheated, undiluted, and thicker fluid—featuring a higher glycol concentration than standard deicers—helps prevent ice buildup while the plane is on the ground. As the aircraft takes off, the anti-icing fluid naturally runs off, leaving a clean surface for safe flight.
In-flight deicing
In-flight deicing systems are designed to control ice formation during flight. These systems include electrically heated surfaces and pneumatic boots on wings and tail surfaces. They prevent or remove ice accumulation by applying heat or physically breaking up the ice.
Modern planes often incorporate bleed air systems too, plus structural pathways that distribute engine-generated heat throughout the aircraft. These systems ensure that various surfaces remain heated, helping to prevent the formation of ice and maintain optimal conditions for safe flight in cold weather.
Airport runways deicing
Deicing is not limited to aircraft: it also extends to airport infrastructure. Runways and taxiways must also be kept clear of ice and snow to ensure safe takeoffs and landings. Airports use snowploughs, brooms and deicing chemicals to keep these surfaces free from winter precipitation.
How long does it take?
You’ve probably noticed this procedure happen before your eyes while waiting for a plane to take off. The duration of the deicing process depends on factors such as the size of the aircraft, weather conditions and the type of deicing fluid used.
Generally, ground deicing can take anywhere from 10 to 30 minutes, with larger aircraft taking more time.
Deicing chemicals used
Commonly used chemicals include sodium chloride, potassium acetate, calcium magnesium acetate, potassium formate and propylene glycol. These fluids have low freezing points, allowing them to stay in liquid form even in cold temperatures.
Sustainability and environmental concerns
While deicing is crucial for aviation safety, there are environmental considerations associated with the chemicals being used. Efforts are underway to develop more environmentally friendly deicing fluids and methods. Additionally, airports often have systems in place to collect and treat runoff fluids to minimize environmental impact.
Accidents linked to icing and ice management failures
Aero Trasporti Italiani Flight 460
On October 15, 1987, this scheduled flight from Milan Linate Airport, Italy, to Cologne Bonn Airport, Germany, crashed into a 2,300-foot mountain after an uncontrolled descent. Ice formed on the wings of the ATR 42, and the crew failed to recognize that the combination of ice and low speed caused the plane to stall. All 37 onboard were killed.
USAir Flight 405
On March 22, 1992, a USAir Fokker F28 flying from LaGuardia Airport, New York, to Cleveland, Ohio, crashed shortly after takeoff in poor weather. Ice on the wings disrupted airflow, preventing the aircraft from gaining lift. It veered off the runway and into Flushing Bay, killing 27 of the 51 people onboard, including the captain and a cabin crew member.
American Eagle Flight 4184
On October 31, 1994, this flight from Indianapolis, Indiana, to Chicago, Illinois, crashed into a field after losing control in severe icing conditions. Ice accumulated beyond the deice boots of the ATR 72, causing an unexpected aileron hinge moment reversal. All 68 onboard died in the high-speed impact.
