A modular landing port for use on a top of a building structure. The modular landing port includes a base portion. One or more landing module extend from the base portion. The one or more landing modules have a first end provide proximate the base portion and a second end spaced from the base portion. Each of the one or more landing modules have a landing/take-off zone proximate the second end and at least one loading/unloading zone proximate the first end. The landing/take-off zone and the at least one loading/unloading zone are configured to receive a vertical take-off and landing aircraft.

An acoustic attenuation panel includes a cellular structure including a plurality of acoustic cells separated from one another by peripheral partitions, a perforated acoustic structure, the perforated acoustic structure and the cellular structure being formed in one piece in a first material, and a porous acoustic layer formed of a second material and fastened to a surface of the perforated acoustic structure by entangling the first material and the second material.

An acoustic attenuation panel includes a cellular structure including a plurality of acoustic cells separated from one another by peripheral partitions, a perforated acoustic structure, the perforated acoustic structure and the cellular structure being formed in one piece in a first material, and a porous acoustic layer formed of a second material and fastened to a surface of the perforated acoustic structure by entangling the first material and the second material.

The exemplary arrangements provide a system of selectively moving airplanes on an airport apron. Airplanes are selectively moved from selected parking locations to areas adjacent to take-off locations such as runways. Airplanes may also be selectively moved from an area of the apron adjacent to a landing location to a parking location. This may include for example an unloading location, an airport terminal, a servicing location, a fueling location, storage location and/or other suitable location. The exemplary systems include driving channels through which a carriage is selectively moved. The carriage is in operative connection with a basket for operatively engaging at least one front wheel of selected airplanes for purposes of transporting such airplanes to and between the desired locations.

The exemplary arrangements provide a system of selectively moving airplanes on an airport apron. Airplanes are selectively moved from selected parking locations to areas adjacent to take-off locations such as runways. Airplanes may also be selectively moved from an area of the apron adjacent to a landing location to a parking location. This may include for example an unloading location, an airport terminal, a servicing location, a fueling location, storage location and/or other suitable location. The exemplary systems include driving channels through which a carriage is selectively moved. The carriage is in operative connection with a basket for operatively engaging at least one front wheel of selected airplanes for purposes of transporting such airplanes to and between the desired locations.

The exemplary embodiments provide a system of selectively moving airplanes on an airport apron. Airplanes are selectively moved from selective parking locations to areas adjacent to take-off locations such as runways. Airplanes may also be selectively moved from an area of the apron adjacent to a landing location and/or to a parking location. This may include for example an unloading location, an airport terminal, a servicing location, a fueling location, storage location and/or other suitable location. The exemplary system includes driving channels through which a carriage is selectively moved. The carriage includes a basket for operatively engaging at least one front wheel of selected airplanes for purposes of transporting such airplanes to and between the desired locations.

The exemplary embodiments provide a system of selectively moving airplanes on an airport apron. Airplanes are selectively moved from selective parking locations to areas adjacent to take-off locations such as runways. Airplanes may also be selectively moved from an area of the apron adjacent to a landing location and/or to a parking location. This may include for example an unloading location, an airport terminal, a servicing location, a fueling location, storage location and/or other suitable location. The exemplary system includes driving channels through which a carriage is selectively moved. The carriage includes a basket for operatively engaging at least one front wheel of selected airplanes for purposes of transporting such airplanes to and between the desired locations.

A sound absorbing structure includes a wall having a first side and a second side and at least one acoustic scatterer coupled to a first side of the wall. The first side of the wall may be positioned to face a source of noise, such as moving motor vehicles, airplanes, and the like. The at least one acoustic scatterer has an opening and at least one channel. The at least one channel has a channel open end and a channel terminal end with the channel open end being in fluid communication with the opening.

A sound absorbing structure includes a wall having a first side and a second side and at least one acoustic scatterer coupled to a first side of the wall. The first side of the wall may be positioned to face a source of noise, such as moving motor vehicles, airplanes, and the like. The at least one acoustic scatterer has an opening and at least one channel. The at least one channel has a channel open end and a channel terminal end with the channel open end being in fluid communication with the opening.

Routes for performing missions such as deliveries by air within a region may be selected based on historic exposures to noise within the region. Where a plurality of missions are performed by aerial vehicles at or near locations within a region, noises radiated by such aerial vehicles during such missions may be tracked or determined, and the extent to which ground-based locations are exposed to such noises may be modeled accordingly. Subsequently, when another mission is to be performed by air within the region, aspects of an optimal route to be traveled by an aerial vehicle while performing the mission, including but not limited to courses, speeds, altitudes, orientations or operational characteristics of the aerial vehicle, as well as paths to be traveled by the aerial vehicle or waypoints to be reached, may be selected in a manner that takes into account historical exposures to noises within the region.