aircraft de-icing

The average traveler knows that there are pre-flight operations that need to be carried out for safety. One such activity is aircraft de-icing. Many people are very confused about the necessity and frequency of this process, which creates unnecessary worry. Keep reading to dispel aircraft de-icing myths.

Icy Conditions

Aircraft de-icing doesn’t only occur in the winter months. Aircraft travel at a height of 36,000 – 40,000 feet, where the temperature is much different than on the ground. At that altitude, the temperature can be less than 30 degrees Fahrenheit. Water vapor in the air can cause droplets to collect on an aircraft, at such cool temperatures the droplets can freeze.

Location & Timing

De-icing doesn’t take place until the aircraft has already been boarded. Once de-icing fluid has been applied, the “hold over” time begins. Hold over time refers to the length of time it takes for an aircraft to accumulate snow or ice after the initial treatment. Boarding can take up to 45 minutes on larger aircraft, by de-icing after boarding the hold over time is significantly reduced.

De-icing typically takes place on a designated de-ice pad. The de-ice pad is set-up with drainage to prevent excess de-icing and anti-icing from getting into storm drains. Reservoirs are put in place to collect the excess. The de-ice pad has plenty of room around it, providing easier access to the ground crew applying the de-icing agents.

Safety Concerns

The fumes created by de-icing agents are not hazardous to the ground crew or aircraft passengers. The smell from the de-icing and anti-icing agents can sometimes smell similar to maple syrup. Due to the strong smell, some pilots temporarily disable the ventilation system.

The last commercial aircraft crash due to icing was in 1994 in the US. In response to ice-caused accidents, the FAA updated airworthiness directives. Aircraft are required to go through necessary steps to de-ice before flight. Aircraft manufacturers include better anti-icing systems in modern aircraft. Aircraft are grounded if internal de-icing systems are not fully operational.