Perpustakaan Digital ITB

Detecting unstabilized approach is crucial for flight safety. One of the methods used to detect unstabilized approach is the energy management method. The energy management method focuses on assessing the aircraft’s energy state within an ideal energy range during the approach phase. The energy management model is influenced by the glide slope angle of the destination airport and the specific approach reference speed for each aircraft type, utilizing flight data from a single aircraft type landing at the same location. The energy management method takes into account nine contributing factors to the outcome. Stochastic sensitivity analysis is conducted by varying inputs using Monte Carlo simulations, where input variations are based on actual data from 2073 flights collected through the Flight Data Monitoring (FDM) program. Sensitivity analysis is performed by introducing variations to the inputs in the energy management model. Input variations are applied to each factor contributing to unstabilized approach while keeping other factors constant according to standard operational conditions represented by reference flights. Sensitivity levels are measured by ranking factors contributing to approach instability based on standard deviation and minimal-maximal range of energy outputs for each factor. More significant standard deviations and ranges in energy outputs indicate higher sensitivity levels. Based on sensitivity analysis results, the sequence of sensitivity levels for factors contributing to approach instability is as follows: altitude (h), pitch angle (?), groundspeed (v), angle of attack (?), engine thrust (N1), lift coefficient (CL), aircraft mass (m), air density (?), and coefficient of drag in zero-lift condition (CD0).