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Takeoff and landing
Published in Mohammad H. Sadraey, Aircraft Performance, 2017
The aircraft primary takeoff performance is often determined by the required runway. The shorter the runway, the better is the aircraft takeoff performance. In aircraft carriers, other techniques and devices such as catapult are provided to make takeoff and landing feasible and make takeoff run and landing run shorter. An aircraft that could take off and land in a runway with a length of less than 500 ft is called STOL (short takeoff and landing). The aircraft that is able to take off and land vertically are referred to as VTOL (vertical takeoff and landing). These two groups of aircraft are referred to as V/STOL aircraft. Most fighters are of V/STOL type. V-22 Osprey, Harrier AV-8B, and Bell XV-15 are examples of VTOL aircraft.
UAS Airframe and Powerplant Design
Published in Douglas M. Marshall, R. Kurt Barnhart, Eric Shappee, Michael Most, Introduction to Unmanned Aircraft Systems, 2016
Multi-rotors exist mainly in quad-, hexa-, and octocopter configurations. Notice that all have an even number of rotors for torque cancellation. (Though much less common, three rotor, “Y-frame” multi-rotor designs also exist, but these must use a tail rotor or rotor tilting, which greatly complicates flight dynamics and aircraft control, to counteract the torque effect induced by an odd number of rotors.) Current manufacturers of sUAS multirotors include DJI, Aerobot and Aeryon. Multi-rotors are almost exclusively small UASs, powered by electric motors. They afford the advantages of VTOL flight, the ability to hover and loiter on station, agility, and a relative freedom from vibration, but at the expense of limited range, altitude, and endurance.
Exploring the User Acceptance of Urban Air Mobility: Extending the Technology Acceptance Model with Trust and Service Quality Factors
Published in International Journal of Human–Computer Interaction, 2023
Young Woo Kim, Cherin Lim, Yong Gu Ji
UAM vehicle, also known as a vertical takeoff and landing (VTOL) aircraft, is a key technology that enables air travel within the urban areas (Straubinger et al., 2021). UAM vehicles will be capable of carrying out vertical takeoff and landing but are distinguishable from existing urban aerial vehicles such as helicopters by their technical structures. VTOL aircrafts adopt an electrical distributed propulsion system that can improve the stability of aircraft through independent control of several motors (Holden & Goel, 2016). Porsche Consulting proposed three vertical mobility concepts that employ either a multirotor system, a lift-and-cruise combination, and a tilt-X system, each with a travel speed ranging between 70 and 300 km/h (Grandl et al., 2018). The EHang 216 is composed of multiple motors and coaxial propellers and can travel a short-to-medium ranged distance (3–100 km) at a flight elevation of under 800 m (Xu, 2020).
Particle swarm optimization based proportional-derivative parameters for unmanned tilt-rotor flight control and trajectory tracking
Published in Automatika, 2020
Nada El Gmili, Mostafa Mjahed, Abdeljalil El Kari, Hassan Ayad
Unmanned Aerial Vehicles (UAVs) are rapidly becoming more popular due to the recent technological advancements in many civilian and military applications, including photography, agricultural support, natural disaster support, earth science research assistance, hostile zone reconnaissance, hazardous biological or chemical agent detection, border detection, etc. These diversified applications have created the need for a single aerial vehicle with the ability to efficiently perform multiple tasks. Within this scope, different models that have received attention are aircrafts with a tilting mechanism known as tilt-rotors. These aerial vehicles combine the capabilities of rotorcraft models (hovering, aggressive manoeuvring, vertical take-off/ landing (VTOL)), with those of fixed wing models (speed, flight endurance). The focus of this paper is on VTOLs that have two rotors adjusted in tandem. The two rotors are independently coupled with a type of revolute joint, typically a servomotor, with the ability to tilt the entire rotor.
Static and modal analysis of a crankshaft reciprocating driver for reciprocating-airfoil (RA) driven VTOL aircraft
Published in Mechanics Based Design of Structures and Machines, 2023
Mohammad Didarul Alam, Yiding Cao
Because of few available routes and an exponential increase in the number of vehicles, millions of hours are wasted on the road worldwide every day due to traffic congestion. On the other hand, commercial fixed-wing airplanes continue to face challenges to be the future of transportation. Although fixed-wing airplanes have become mass transportation systems, the runway requirement for takeoff and landing and massive airport maintenance are making air travel expensive and inconvenient, especially for poor people. Helicopters could be a convenient way for transportation, but the current helicopters are too noisy, inefficient, polluting, and expensive for mass-scale use, as well as unreliable for large-scale commercial transportation. There are several technologies showing promise to overcome the current challenges such as new vertical takeoff and landing (VTOL) vehicles, hyperloop, and maglev train. Among them, the VTOL vehicle is the most promising technology and considered to be the future of air transportation. In this technology, VTOL aircraft including air taxi and drones can take off directly from the position of passengers and land at the desired destinations. They do not need to follow any fixed routes like trains, buses, cars, etc. so that route-based congestion would be less prevalent. Therefore, it has the huge potentiality to save time in both intra-city and inter-city transportation. Also, it would be quieter, faster, cleaner, more efficient, and safer. In a nutshell, VTOL transportation is considered a grand challenge for the world that could revolutionize the passenger transportation system as well as improve people’s lifestyles.