Accurate identification of aircraft noise abatement procedures (NAPs) is essential for reliable environmental impact assessment and noise modelling. However, current analyses of the implementation of noise abatement procedures are mainly based on interviews with airlines. Previous studies establish methods to model NADP procedures and estimate flap settings. However, only limited studies have proposed methods for classifying noise abatement procedures. This study presents a data-driven approach for the classification of Noise Abatement Departure Procedure (NADP), Continuous Descent Approaches (CDA) and Reduced Flap Setting Approach using flight trajectory data. The framework integrates energy-based performance, flight performance indicators and machine learning techniques to classify flight trajectories into specific noise abatement procedures. The methodology is applied to operations at Amsterdam Airport Schiphol, evaluated on a dataset comprising over 19,000 inbound and over 19,000 outbound flight data in May 2025, alongside a machine learning training dataset of over 7,000 inbound flights. The results indicate that the developed framework is capable of classifying flight trajectories from enhanced mode-S and radar data to specific noise abatement procedures. However, the developed framework is constrained mainly by data resolution and feature sensitivity. Future work should focus on improving temporal resolution, expanding the dataset and incorporating event-based validation for enhancing model reliability. ... Read more

This report entails the design of a regional passenger aircraft, serving 48 passengers and entering the market by 2035. It is known as the SRP-22 ALAR FOX, however, in general, SRP-22 is used. The propulsion system is designed with hydrogen as its fuel. The hydrogen is converted to electricity with a low-temperature proton-exchange membrane fuel cell, which in turn is used by the electric motors, to power the propellers. There are four electric motors with one six-bladed propeller each. Two propellers are located under the wing near the fuselage and deliver 80% of the total power. The remaining two propellers are positioned on the wing tips, delivering the remaining 20%. The benefit of these wingtip propellers is an expected drag reduction of around 10%, due to the attenuation of wingtip vortices.
The hydrogen is stored in a composite tank, located behind the aft pressure bulkhead. The fuel cell is placed under the cabin floor, just in front of the pressure bulkhead, such that less tubing is required to transport the hydrogen. The boil-off of the hydrogen is used to transform the hydrogen from its liquid state to its gaseous state, through the usage of glass rods. After that, the hydrogen is heated up until about 80◦C, which is the operating temperature of the fuel cell. The control system is controlled through a mechanical-powered hydraulic system. The elevator design includes horns to relieve the hinge moment.
One of the main goals was to reduce the environmental impact of the aircraft. The average temperature response of the SRP-22 is almost 83 times lower than that of the ATR 42 by 2064, which supports this goal. Noise has also been taken into account, which mainly stems from the propellers and airframe. It is found that the noise levels are well below the limits set by ICAO. The unit list price of the SRP-22 will be $19 million when using more optimistic fuel cell prices, while a least optimistic estimate results in a unit list price of $37 million. Moreover, the direct operational cost is around 10% lower than those of the ATR 72. Because of the usage of electric motors, the maintenance cost is expected to be lower than for a turboprop aircraft. ... Read more