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obstacle-free zone
- Definição1
- The airspace above the inner approach surface, inner transitional surfaces, and balked landing surface and that portion of the strip bounded by these surfaces, which is not penetrated by any fixed obstacle other than a low-mass and frangibly mounted one required for air navigation purposes.
- Fonte1
- INTERNATIONAL CIVIL AVIATION ORGANIZATION. International civil aviation vocabulary. 3rd ed. Montreal, 2007. (Doc. 9713)
- Definição2
- The obstacle-free zone is a three-dimensional volume of airspace set up to protect aircraft transitioning to and from the runway. The OFZ clearing standard precludes taxiing and parked airplanes and object penetrations, except for frangible NAVAID (navigational aid) locations that are fixed by function. Additionally, vehicles, equipment, and personnel may be authorized by ATC (air traffic control) to enter the area in accordance with the rules in force. The runway OFZ - and when applicalbe, the inner-approach OFZ - and the inner-transational OFZ, compose the OFZ. The runway OFZ is a defined volume of airspace centrered above the runway. It is the airspace above a surface whose elevation at any point is the same as the elevation of the nearest point on the runway centerline. It extends 200 ft (60 m) beyond each end of the runway. The width is as follows: 1. For runways serving large airplanes, it is the greater of (a) 400 ft (120 m) or (b) 180 ft (54 m) plus the wingspan of the most demanding airplane plus 20 ft per 1000 ft of airport elevation. 2. For runways serving only small airplanes, it is: (a) 300 ft (90 m) for precision instrument runways; (b) 250 ft (75 m) for other runways serving small airplanes with approach speeds of 50 knots, or more; (c) 120 ft (36 m) for other runways serving small airplanes with approach speeds of less than 50 knots. The inner-approach OFZ is defined volume of airspace centered of theapproach area. It applies only to runways with an approach lighting system. It begins 200 ft (60 m) from the runway threshold and extends 200 ft (60 m) beyond the last light unit in the approach light system. The width of the inner-approach OFZ is the same of 50 (horizontal) to 1 (vertical) from the beginning. The inner-transitional surface OFZ is a defined volume of airspace along the sides of the runway and the inner-approach OFZ, and it applies only to precision instrument runways. The inner-transational suface OFZ slopes 3 (horizontal) to 9 (vertical) out from the edges of the runway OFZ and the inner-approach OFZ to a hight of 150 ft (50 m) above the established airport elevation.
- Fonte2
- KUMAR, Bharat (ed.). An illustrated dictionary of aviation. New York: McGraw-Hill, c2005. 752 p.
- Nota Adicional1
- Acronym in English: OFZ.
- Subárea
- Airport Infrastructure
- Related Term
- clearway
- Français
- zone dégagée d’obstacles