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Intentional electrical connection to a reference conducting plane, which may be earth, but which more generally consists of a specific array of interconnected electrical conductors referred to as the grounding conductor.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.


Intentional electrical connections to a reference conducting plane, which may be earth (hence the term ground), but which more generally consists of a specific array of interconnected electrical conductors, referred to as the grounding conductor. The symbol which denotes a connection to the grounding conductor is three parallel horizontal lines, each of the lower two being shorter than the one above it (Fig. 1). The electric system of an airplane or ship observes specific grounding practices with prescribed points of grounding, but no connection to earth is involved. A connection to such a reference grounding conductor which is independent of earth is denoted by use of the symbol shown in Fig. 2.

The subject of grounding may be conveniently divided into two categories: system grounding and equipment grounding. System grounding relates to a grounding connection from the electric power system conductors for the purpose of securing superior performance qualities in the electrical system. Equipment grounding relates to a grounding connection from the various electric-machine frames, equipment housings, metal raceways containing energized electrical conductors, and closely adjacent conducting structures judged to be vulnerable to contact by an energized conductor. The purpose of such equipment grounding is to avoid environmental hazards such as electric shock to area occupants, fire ignition hazard to the building or contents, and sparking or arcing between building interior metallic members which may be in loose contact with one another. The design of outdoor open-type installations presents special problems.

Installations in which earth is used as a reference ground plane present special problems. To design an earth “floor surface” for an outdoor open-type substation which will be free of dangerous electric shock voltage exposure to persons around the station is a difficult task.

McGraw-Hill Concise Encyclopedia of Engineering. © 2002 by The McGraw-Hill Companies, Inc.


i. Declaring a pilot or an aircraft unfit to fly by the competent authority.
ii. Connecting a conductor to a ground or earth circuit.
An Illustrated Dictionary of Aviation Copyright © 2005 by The McGraw-Hill Companies, Inc. All rights reserved
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Mann, an airline industry consultant in Port Washington, New York, described what a grounding entails and the factors regulators consider when making the decision to order one.
* errors in the identification of horizontal groundings (acceptance of cables and underground communications as an artificial grounding);
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In risk analysis of ship accidents, especially collisions, groundings (include grounding [impact with individual shoals and islands in the fairway], and strandings [impact with the coastline] (Kristiansen 2005)), in addition to statistical methods there are methods that are based on the calculation of the actual number of accidents from their potential number.
Coral reef recovery from disturbances such as ship groundings is dependent on coral settlement, survival, and growth to larger size classes.
An overall view on groundings categorizes the accidents in two major groups:
The company's shares rose three per cent in early trading and also lifted the stocks of other airlines, providing some relief to a sector that has been battered by thousands of flight cancellations and reschedules in the wake of the grounding.
The groundings come during a time when flydubai is already making operational changes to account for the closure of one of the two runways at its hub Dubai International Airport.
However, the impact on the formation of electrical characteristics of the GD of electrical installations, which can have natural concentrated groundings is not taken into account in this work not taken into account.