Aeronautical Terms beginning with O

OAT

Outside Air Temperature

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OBS

Omni-bearing Selector

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OCA

Ocean Control Area

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OCNL

Occasional

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OCS

Obstacle Clearance Surface

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ODALS

Omnidirectional Approach Lighting System Consists of seven omnidirectional flashing lights located in the approach area of a nonprecision runway. Five lights are located on the runway centerline extended with the first light located 300 feet from the threshold and extending at equal intervals up to 1,500 feet from the threshold. The other two lights are located, one on each side of the runway threshold, at a lateral distance of 40 feet from the runway edge, or 75 feet from the runway edge when installed on a runway equipped with a VASI.

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ODAPS

Oceanic Display And Planning System

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ODP

Obstacle Departure Procedures.

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OEI

One Engine Inoperative.

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OEM

Original Equipment Manufacturer

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OFCM

OVC overcast

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Office

Of the Federal Coordinator for Meteorology

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OHD

Overhead

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OM

Outer Marker.

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OMO

One-Minute Observation

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OPC

Ocean Prediction Center

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OPMET

Operational Meteorological

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OpSpec

Operation Specification

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OPSPECS

Operations Specifications.

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OpsSpecs

Operations Specifications

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OROCA

Off-Route Obstruction Clearance Altitude

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OSV

Operational Service Volume

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OTC

Over-the-Counter

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OTS

Out of service

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