.png)
D-ISCV, positioning to Geneva with two pilots and no passengers, was de-iced before departure after an overnight temperature of -5°C. Type 2 fluid (75% fluid/25% water) was applied at 60°C, completed at 0842 hrs, with a tactile check confirming ice had melted, though the crew noted the fluid didn’t “steam” as much as usual.
Take-off began normally at 0910 hrs from Runway 21. At VR (102 kt), the pilot flying applied back pressure to rotate but felt no response from the aircraft. Further aft pressure produced the same result, prompting a rejected takeoff at 110 kt near the runway midpoint. Heavy braking was needed to stop within the remaining distance; at around 30 kt the aircraft slid right off the runway onto grass, stopping about 15 m from the edge with no damage or injuries.
Post-incident inspection found no mechanical faults in the flight controls or engines. An unfitted oil filler cap was noted but ruled irrelevant. More de-icing fluid than expected remained on the wings, though within normal application parameters and consistent with manufacturer guidance.
The AAIB concluded no mechanical control issue existed. Instead, the manufacturer’s flight manual notes that heavier-than-normal elevator forces can occur after de-icing — likely explaining the pilot’s perception of unresponsive controls. The runway excursion during the RTO was probably caused by asymmetric (differential) brake pedal pressure rather than any surface or fluid contamination issue.A known de-icing-related control-force phenomenon was misinterpreted as a mechanical fault, triggering an RTO and subsequent runway excursion from differential braking.
Do briefings and SOPs cover known post-de-icing handling characteristics?
Photo Source: Alec Wilson from Khon Kaen, Thailand, CC BY-SA 2.0, via Wikimedia Commons