While en-route from Amsterdam to Rome on May 23, a KLM Cityhopper Embraer ERJ-190 decided to return to Amsterdam after reporting an "anti-ice leak in the wing." The aircraft in question was operating as KLM flight number KL-1601 from Schiphol Airport (AMS) to Rome–Fiumicino International Airport (FCO) in Italy.

While cruising in German airspace at 37,000 feet some 90 nautical miles southeast of Amsterdam, the pilots decided to turn around after reporting "anti-ice leak in the wing." The reason for returning to Schiphol was because the anti-ice leak would have prevented the aircraft, registration number PH-EZD, from entering icing conditions or leaving Rome once it had landed.

The Brazilian-built regional jet landed safely back in Amsterdam some 25 minutes later. According to the aviation incident website, The Aviation Herald, a replacement aircraft, an E190 with registration PH-EZF, took the passengers to Rome with a delay of two hours and 15 minutes.

What is an anti-ice leak?

Modern jet airliners use hot air generated from their engines to heat the leading edge of the wing to prevent icing. The principal is very similar to hot water radiators in a house, except hot air travels through the pipes rather than hot water. In an aircraft, the hot air enters a piccolo tube and heats the leading edge of the wing, making it impossible for ice to form. Should a hot air leak be detected, the wing anti-ice valve on the affected side will automatically close.

KLM grounded coronavirus
KLM Cityhopper is based at Schiphol Airport. Photo: Getty Images

Ice can build up on aircraft both on the ground or during flight. On the ground, ice occurs when precipitation freezes on unprotected surfaces, like how your car looks if it is left outside during the winter. To get rid of this ice, the ground crew will spray the plane with a chemical liquid to melt the ice. In the air, icing occurs when aircraft fly through clouds made up of small water droplets. As the aircraft passes through the cloud water droplets are attracted to the surface of the plane and freeze.

When ice forms, it reshapes the lift-producing surface of the wing, causing more drag than lift. If the ice continues to build up, you lose lift and eventually stall.

About KLM Cityhopper

KLM Cityhopper is a wholly-owned subsidiary of the Dutch national flag carrier KLM based at Schiphol Airport in the Netherlands. First established in 1991 as a regional airline with the largest fleet of Fokker aircraft in Europe, KLM has now traded up to an all Embraer fleet of modern jets. As a member of the SkyTeam airline alliance, KLM Cityhopper acts as a feeder airline for KLM and its global network of international destinations.

KLM premium economy getty images

According to Planespotters.net, KLM Cityhopper operates a fleet of 48 aircraft comprised of 17 Embraer ERJ-175s and 31 Embraer ERJ-190s.

Have you ever flown with KLM Cityhopper and their Embraer jets before? Share your experience in the comments.