National Ground Stop
Encyclopedia
A ground stop is when all aircraft
at an airport
are forbidden to depart
(and possibly forbidden to land
). This most often occurs during a thunderstorm
, due to the danger of wind shear
, hail
, or other weather-related hazard. It can also occur due to nearby terrorist attacks. Flights already in route may be diverted to other cities, while those that have not departed are held at their airports, so as not to create a backlog
of aircraft circling or trying to land. Airline
s have occasionally held passenger
s on aircraft for hours during ground stops.
Aircraft
An aircraft is a vehicle that is able to fly by gaining support from the air, or, in general, the atmosphere of a planet. An aircraft counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil, or in a few cases the downward thrust from jet engines.Although...
at an airport
Airport
An airport is a location where aircraft such as fixed-wing aircraft, helicopters, and blimps take off and land. Aircraft may be stored or maintained at an airport...
are forbidden to depart
Takeoff
Takeoff is the phase of flight in which an aerospace vehicle goes from the ground to flying in the air.For horizontal takeoff aircraft this usually involves starting with a transition from moving along the ground on a runway. For balloons, helicopters and some specialized fixed-wing aircraft , no...
(and possibly forbidden to land
Landing
thumb|A [[Mute Swan]] alighting. Note the ruffled feathers on top of the wings indicate that the swan is flying at the [[Stall |stall]]ing speed...
). This most often occurs during a thunderstorm
Thunderstorm
A thunderstorm, also known as an electrical storm, a lightning storm, thundershower or simply a storm is a form of weather characterized by the presence of lightning and its acoustic effect on the Earth's atmosphere known as thunder. The meteorologically assigned cloud type associated with the...
, due to the danger of wind shear
Wind shear
Wind shear, sometimes referred to as windshear or wind gradient, is a difference in wind speed and direction over a relatively short distance in the atmosphere...
, hail
Hail
Hail is a form of solid precipitation. It consists of balls or irregular lumps of ice, each of which is referred to as a hail stone. Hail stones on Earth consist mostly of water ice and measure between and in diameter, with the larger stones coming from severe thunderstorms...
, or other weather-related hazard. It can also occur due to nearby terrorist attacks. Flights already in route may be diverted to other cities, while those that have not departed are held at their airports, so as not to create a backlog
Backlog
Backlog generally refers to an accumulation over time of work waiting to be done or orders to be fulfilled.Backlog may also refer to:*different kinds of backlogs exist for different time scales in Scrum...
of aircraft circling or trying to land. Airline
Airline
An airline provides air transport services for traveling passengers and freight. Airlines lease or own their aircraft with which to supply these services and may form partnerships or alliances with other airlines for mutual benefit...
s have occasionally held passenger
Passenger
A passenger is a term broadly used to describe any person who travels in a vehicle, but bears little or no responsibility for the tasks required for that vehicle to arrive at its destination....
s on aircraft for hours during ground stops.
See also
Security Control of Air Traffic and Air Navigation Aids (SCATANA)Security Control of Air Traffic and Air Navigation Aids
The Plan for the Security Control of Air Traffic and Air Navigation Aids is an emergency preparedness plan of the United States which prescribes the joint action to be taken by appropriate elements of the Department of Defense, Federal Aviation Administration, and the Federal Communications...