Devenition And Abreviation Aeronautical Telecommunication (Alphabet O, P, Q)

Observation (meteorological). The evaluation of one or more meteorological elements. 

Obstacle. All fixed (whether temporary or permanent) and mobile objects, or parts thereof, that are located on an area intended for the surface movement of aircraft or that extend above a defined surface intended to protect aircraft in flight. 

Obstacle clearance altitude (OCA) or obstacle clearance height (OCH). The lowest altitude or the lowest height above the elevation of the relevant runway threshold or the aerodrome elevation as applicable, used in establishing compliance with appropriate obstacle clearance criteria. 

Obstacle free zone (OFZ). 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. 

Obstacle/terrain data collection surface. A defined surface intended for the purpose of collecting obstacle/terrain data. Offset frequency simplex. A variation of single channel simplex wherein telecommunication between two stations is effected by using in each direction frequencies that are intentionally slightly different but contained within a portion of the spectrum allotted for the operation. 

Ohm (Ω). The electric resistance between two points of a conductor when a constant difference of potential of 1 volt, applied between these two points, produces in this conductor a current of 1 ampere, this conductor not being the source of any electromotive force. 

Open systems interconnection (OSI) reference model. A model providing a standard approach to network design introducing modularity by dividing the complex set of functions into seven more manageable, self-contained, functional layers. By convention these are usually depicted as a vertical stack. 

Open Water. Means a water mass which does not have any landmasses within the maximum times or distances prescribed by a regulation. 

Operate, with respect to aircraft, means use, cause to use or authorize to use aircraft, for the purpose (except as provided in 91.13 of this chapter) of air navigation including the piloting of aircraft, with or without the right of legal control (as owner, lessee, or otherwise). 

Operator means a person, organization or enterprise engaged in or offering to engage in an aircraft operation. 

Operational control. The exercise of authority over the initiation, continuation, diversion or termination of a flight in the interest of the safety of the aircraft and the regularity and efficiency of the flight. 

Operational control communications. Communications required for the exercise of authority over the initiation, continuation, diversion or termination of a flight in the interest of the safety of the aircraft and the regularity and efficiency of a flight.

Operational Control System (OCS). Means an air carrier’s system for the exercise of authority over the formulation, execution and amendment of an operational flight plan in respect of a flight or series of flights. 

Operational flight plan. The operators plan for the safe conduct of the flight based on considerations of aeroplane performance, other operating limitations and relevant expected conditions on the route to be followed and at the aerodromes concerned Operator’s maintenance control manual. A document which describes the operator’s procedures necessary to ensure that all scheduled and unscheduled maintenance is performed on the operator’s aircraft on time and in a controlled and satisfactory manner. 

Operations manual. A manual containing procedures, instructions and guidance for use by operational personnel in the execution of their duties. 

Operational planning. The planning of flight operations by an operator.  

Operation Specifications (OPSPEC) means the data approved by DGCA attached to the certificate of organization approval, include operation limitation of the organization. 

Ornithopter. A heaver-than-air aircraft supported in flight chiefly by the reactions of the air on planes to which a flapping motion is imparted. 

Orthometric height. Height of a point related to the geoid, generally presented as an MSL elevation.
Overseas air commerce --- Reserve.
 

Overseas air transportation means the carriage by aircraft of persons or property as a common carrier for compensation or hire, or the carriage of mail by aircraft. Over the top means above the layer of clouds or other obscuring phenomena forming the ceiling. 

Oxides of nitrogen. The sum of the amounts of the nitric oxide and nitrogen dioxide contained in a gas sample calculated as if the nitric oxide were in the form of nitrogen dioxide.
 

Packet. The basic unit of data transfer among communications devices within the network layer. 

Packet layer protocol (PLP). A protocol to establish and maintain a connection between peer level entities at the network layer, and to transfer data packets between them. In the context of this standard, the term refers to the protocol defined by the ISO 8208 standard used in this document. 

Package. The complete product of the packing operation consisting of the packaging and its contents prepared for transport. 

Packaging. Receptacles and any other components or materials necessary for the receptacle to perform its containment function. 

Parachute means a device used or intended to be used to retard the fall of a body or object through the air. Pascal (Pa). The pressure or stress of 1 newton per square metre. 

Passenger. Any person on board an aircraft during flight time, who is not acting as a crewmember. 

Passenger aircraft. An aircraft that carries any person other than a crew member, an operator’s employee in an official capacity, an authorized representative of an appropriate national authority or a person accompanying a consignment or other cargo. 

Performance Class 1 helicopter. A helicopter with performance such that, in case of critical power-unit failure, it is able to land on the rejected take-off area or safely continue the flight to an appropriate landing area, depending on when the failure occurs.

Performance Class 2 helicopter. A helicopter with performance such that, in case of critical power-unit failure, it is able to safely continue the flight, except when the failure occurs prior to a defined point after take-off or after a defined point before landing, in which cases a forced landing may be required. 

Performance Class 3 helicopter. A helicopter with performance such that, in case of power-unit failure at any point in the flight profile, a forced landing must be performed. 

Performance management. An ATN systems management facility to monitor and evaluate the performance of the systems. 

Person means an individual, firm, partnership, corporation, company, association, joint-stock association, or governmental entity. It includes a trustee, receiver, assignee, or similar representative of any of them. 

Person In respect of an air carrier, means any person who is an owner, or operator of an aircraft listed on that air carrier’s operations specifications or, is otherwise acting as an employee or agent of that air carrier. 

Pilot (to). To manipulate the flight controls of an aircraft during flight time. 

Pilot-in-command. The pilot designated by the operator, or in the case of general aviation, the owner, as being in command and charged with the safe conduct of a flight or the person who: A pilot assigned to act as the Captain of an aircraft.
(1) Has final authority and responsibility for the operation and safety of the flight;
(2) Has been designated as pilot in command before or during the flight; and 

(3) Holds the appropriate category, class, and type rating, if appropriate, for the conduct 

     of the flight. Pilotage means navigation by visual reference to landmarks. 

Pilot Flying (PF). The flight crewmember who is manipulating the flight controls of an aircraft during flight time. 

Pilot Not Flying (PNF). The pilot who is performing tasks during flight time, in support of the pilot flying. 

Pilot Proficiency Check (PPC). A flight check performed in whole or in part, in an aeroplane type simulator or an aircraft. Conducted by a GCP, CCP, or DGCP for the purpose of establishing the level of proficiency, of a flight crewmember. 

Pilot Self-dispatch means a system where authority and responsibility for flight release, operation and flight following have been delegated solely to the PIC. 

Pitch setting means the propeller blade setting as determined by the blade angle measured in a manner, and at a radius, specified by the instruction manual for the propeller. 

Point light. A luminous signal appearing without perceptible length. 

Point-to-point. Pertaining or relating to the interconnection of two devices, particularly end-user instruments. A communication path of service intended to connect two discrete end-users; as distinguished from broadcast or multipoint service. 

Portrayal. Presentation of information to humans (ISO 19117*). 

Position (geographical). Set of coordinates (latitude and longitude) referenced to the mathematical reference ellipsoid which define the position of a point on the surface of the Earth. 

Post spacing. Angular or linear distance between two adjacent elevation points. 

Positive control means control of all air traffic, within designated airspace, by air traffic control. 

Power-unit. A system of one or more engines and ancillary parts which are together necessary to provide thrust, inde- pendently of the continued operation of any other power-unit(s), but not including short period thrust-producing devices. 

Powered-lift means a heavier-than-air aircraft capable of vertical takeoff, vertical landing, and low speed flight that depends principally on engine-driven lift devices or engine thrust for lift during these flight regimes and on nonrotating airfoil(s) for lift during horizontal flight.

Precision. The smallest difference that can be reliably distinguished by a measurement process. Precision approach runway, see Instrument runway.
 

Precision approach procedure. An instrument approach procedure utilizing azimuth and glide path information provided by ILS or PAR.
 

Pre-flight information bulletin (PIB). A presentation of current NOTAM information of operational significance, prepared prior to flight. 

Preliminary Report. The communication used for the prompt dissemination of data obtained during the early stages of the investigation. 

Pressure-altitude. An atmospheric pressure expressed in terms of altitude which corresponds to that pressure in the Standard Atmosphere. 

Prevailing visibility. The visibility value, observed in accordance with the definition of “visibility”, which is reached or exceeded within at least half the horizon circle or within at least half of the surface of the aerodrome. These areas could comprise contiguous or non-contiguous sectors. 

Preventive maintenance means simple or minor preservation operations and the replacement of small standard parts not involving complex assembly operations. 

Primary means of communication. The means of communication to be adopted normally by aircraft and ground stations as a first choice where alternative means of communication exist. 

Primary runway(s). Runway(s) used in preference to others whenever conditions permit. 

Printed communications. Communications which automati-cally provide a permanent printed record at each terminal of a circuit of all messages which pass over such circuit.

Problematic use of substances. The use of one or more psychoactive substances by aviation personnel in a way that: 

a) constitutes a direct hazard to the user or endangers the lives, health or welfare of others; and/or 

b) causes or worsens an occupational, social, mental or physical problem or disorder. 

Procedure altitude/height. A specified altitude/height flown operationally at or above the minimum altitude/height and established to accommodate a stabilized descent at a prescribed descent gradient/angle in the intermediate/final approach segment. 

Procedure turn. A manoeuvre in which a turn is made away from a designated track followed by a turn in the opposite direction to permit the aircraft to intercept and proceed along the reciprocal of the designated track.

Product : 

(1) A Class I product is a complete aircraft, aircraft engine, or propeller, which - (i) Has 

     been type certificated in accordance with this Decree and for which DGCA Approved 

     Specifications or type certificate data sheets have been issued; or (ii) Is identical to a type 

     certificated product specified in paragraph(b)(1)(i) of this section in all respects except as

     is otherwise acceptable to the civil aviation authority of the importing state.
(2) A Class II product is a major component of a Class I product(e.g., wings, fuselages, 

     empennage assemblies, landing gears, power transmissions, control surfaces, etc), the failure 

     of which would jeopardize the safety of a Class I product; or any part, material, or appliance,

     approved and manufactured under the TSO system in the "C" series. 

(3) A Class III product is any part or component which is not a Class I or Class II 

     product and includes standard parts. 

Production Certificate (PC) means A document issued by a DGCA to the aircraft manufacture, which have been meet the appropriate Airworthiness requirements related organization and the production facilities. 

Prohibited area. An airspace of defined dimensions, above the land areas or territorial waters of a State, within which the flight of aircraft is prohibited. 

a) requires hospitalization for more than 48 hours, commencing within seven days 

    from the date the injury was received; or 

b) results in a fracture of any bone (except simple fractures of fingers, toes or nose); or 

c) involves lacerations which cause severe haemorrhage, nerve, muscle or tendon damage; or 

d) involves injury to any internal organ; or 

e) involves second or third degree burns, or any burns affecting more than 5 per cent 

    of the body surface; or f) involves verified exposure to infectious substances or injurious radiation. 

Prognostic chart. A forecast of a specified meteorological element(s) for a specified time or period and a specified surface or portion of airspace, depicted graphically on a chart. 

Propeller means a device for propelling an aircraft that has blades on an engine driven shaft and that, when rotated, produces by its action on the air, a thrust approximately perpendicular to its plane of rotation. It includes control components normally supplied by its manufacturer, but does not include main and auxiliary rotors or rotating airfoils of engines. 

Protected flight zones. Airspace specifically designated to mitigate the hazardous effects of laser radiation. 

Protected service volume. A part of the facility coverage where the facility provides a particular service in accordance with relevant SARPs and within which the facility is afforded frequency protection. 

Psychoactive substances. Alcohol, opioids, cannabinoids, sedatives and hypnotics, cocaine, other psychostimulants, hallucinogens, and volatile solvents, whereas coffee and tobacco are excluded.

Quality. Totality of characteristics of an entity that bear on its ability to satisfy stated and implied needs. 

Quality assurance. All the planned and systematic activities implemented within the quality system, and demonstrated as needed, to provide adequate confidence that an entity will fulfil requirements for quality. 

Quality control. The operational techniques and activities that are used to fulfil requirements for quality. 

Quality management. All activities of the overall management function that determine the quality policy, objectives and responsibilities, and implementing them by means such as quality planning, quality control, quality assurance and quality improvement within the quality system. 

Quality system. The organizational structure, procedures, processes and resources needed to implement quality management.