On 1 February 2015, a Bombardier CRJ 1000 departed from Pamplona with slush likely to have been in excess of the regulatory maximum depth on the runway. On landing at Madrid, the normal operation of the brake units was compromised by ice and one tyre burst damaging surrounding components and leaving debris on the runway, and the other tyre was slow to spin up and sustained a serious flat spot. The Investigation concluded that the Pamplona apron, taxiway and runway had not been properly cleared of frozen deposits and that the flight crew had not followed procedures appropriate for the prevailing conditions.