Probability that a US domestic flight arrives more than 15 minutes late (FAA definition), estimated from information known at scheduling time only. CatBoost inside a scikit-learn pipeline, SHAP explanation of every prediction and an FAA-based expected-loss estimate. Interface in English, Uzbek and Russian. ROC-AUC 0.786 (full model) / 0.779 (compact model served here), recall 0.82 at the chosen threshold 0.37.