We look at what weather-reporting tools are available to predict and identify instrument meteorological conditions. By Ed Brotak | May 25, 2021 Estimated reading time 11 minutes, 17 seconds. Inadvertent or unintentional flight into instrument meteorological conditions (IMC) continues to be a significant cause of fatal helicopter accidents. The crash that killed Kobe Bryant and eight others in January 2020 took place after their helicopter entered clouds during a visual flight rules (VFR) flight. According to the National Transportation Safety Board’s final report on the crash, the pilot succumbed to spatial disorientation and lost control of the helicopter. Another high-profile accident resulting from inadvertent entry into IMC took place on Feb. 2, 2021. On this occasion, an Idaho National Guard helicopter inadvertently entered clouds in mountainous terrain at night. It flew into the side of a mountain just 14 seconds later, killing all three on board.