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Noise emissions from commercial aircraft
Published in Emily S. Nelson, Dhanireddy R. Reddy, Green Aviation: Reduction of Environmental Impact Through Aircraft Technology and Alternative Fuels, 2018
Like slats, flaps are high-lift devices that are installed on the trailing edge of the wing to improve its lift characteristics at the reduced speeds typical of takeoff and landing. When deployed, flaps also increase the drag of the aircraft, allowing it to slow down more rapidly during landing. In addition to the ever-present noise produced by the flap trailing edge, there is also another source of noise generation associated with the flaps when they are deployed. This source is called the flap side-edge noise, or more commonly, flap noise. As can be seen in Figure 1.15, the deployed flap presents a sharp side edge to the flow that is absent when the flap is retracted. When the flap side edge is exposed to the flow, the pressure difference between the suction and pressure sides of the flap results in a crossflow normal to the flap surface. This sets up a complex vortex flow (Streett, 1998) whose interaction with the flap's upper surface is the cause of the flap side-edge noise. It has also been suggested that the turbulence in the flap side-edge vortex may also be another source of flap noise. Flap noise is generally broadband in nature with a complicated directivity pattern (Brooks and Humphreys, 2000).
The Air Traffic Management System
Published in Tom Kontogiannis, Stathis Malakis, Cognitive Engineering and Safety Organization in Air Traffic Management, 2017
Tom Kontogiannis, Stathis Malakis
The takeoff procedure begins when the aircraft enters the runway, once the crew completes the before takeoff checklist. When lined up on the runway and cleared for takeoff, the pilot flying (PF) starts to advance the thrust levers once the engines have spooled up. During the takeoff roll, the pilots cannot reject the takeoff unless specific conditions prevail (e.g., runway incursions, low level windshear warning, engine failure, crew incapacitation).
Situation Awareness and Operating in Today’s Environment
Published in Harry W. Orlady, Linda M. Orlady, John K. Lauber, Human Factors in Multi-Crew Flight Operations, 2017
Harry W. Orlady, Linda M. Orlady, John K. Lauber
The physical state of the airplane is usually shown by cockpit dials, gauges, or instruments. The position of the flaps is indicated by a cockpit gauge, which is usually shown on an analogue gauge in older airplanes and which may be shown on a CRT or flat panel in analogue or digital fashion in high technology airplanes. Selected flap position is confirmed by checking the position of the flap position handle. Leading edge flaps, slats, and trailing edge flaps change the shape of the wing, making it possible to utilize an airfoil that is very efficient at cruise speeds. By adding carefully designed slats and flaps, the airfoil changes so that it is now efficient at takeoff, initial climb, approach, and landing speeds.
A 3D virtual prototype-finite element co-simulation of aircraft hydroplaning on a wet rough runway
Published in International Journal of Pavement Engineering, 2021
Xingyi Zhu, Ming Yang, Shunjie Bai, Hongduo Zhao
In terms of airport runway safety, takeoff and landing safety of aircraft on a wet runway is critical for securing airport safety. In 2015, Boeing released a report of all accidents involving commercial jets that occurred worldwide over 2006–2015. According to flight phase statistics, 23% and 11% of the accidents occurred in the landing and takeoff phases, respectively. Based on the cause of accident, during the takeoff and landing phases, 26% of the accidents involved aircraft that rushed out of the runway (Airplanes 2016). The Dutch Ministry of Traffic Safety analyzed accidents that occurred worldwide, particularly in Europe, in which aircraft ran out of the runway. The study found that wet runways and contaminated runways were the main causes of accidents during the landing and takeoff phases (Pasindu et al. 2012). Van Es (2005) conducted further investigations and found that approximately 48% of the 400 out-of-the-runway accidents occurred on wet runways or on runways covered with a water film. Wet conditions reduce the skid-resistance performance of a runway sharply. Notably, under wet conditions, aircraft landing distance increases by 1.4–2.0 times compared with that on a dry runway (Foundation 2000). Thomas (2011) found that the skid-resistance coefficient between the tire and the road surface may even decrease to <0.1 on a runway submerged under water, which greatly reduces the aircraft landing safety. Therefore, studying the behaviour mechanism of aircraft on a wet runway and formulate relevant countermeasures is necessary.
The Effect of Task Fidelity on Learning Curves: A Synthetic Analysis
Published in International Journal of Human–Computer Interaction, 2023
Frank E. Ritter, Martin K. Yeh, Sarah J. Stager, Ashley F. McDermott, Peter W. Weyhrauch
This analysis approach could also be used to avoid the awkward situation of spending resources to make a simulation/training system more faithful to the external environment by including behavior that is not learned itself but because of the time it takes would none-the-less lead to learning less—tasks that do not get faster and do not get learned are cases where fidelity could be lowered. For example, in contrast to training aircraft, flight simulation trainers do not have to include pre-start checks, taxiing to the runway, flying, or landing—they can teleport the virtual aircraft to the runway for takeoff to practice different kinds of takeoffs with little delays between takeoff attempts.