Pilot/Controller Glossary 

5/19/22 

service in this airspace is delegated to various 
countries, based generally upon geographic proxim-
ity and the availability of the required resources. 

OCEANIC ERROR REPORT

−

 A report filed when 

ATC observes an Oceanic Error as defined by FAA 
Order JO 7210.632, Air Traffic Organization Occur-
rence Reporting. 

OCEANIC PUBLISHED ROUTE

−

 A route estab-

lished in international airspace and charted or 
described in flight information publications, such as 
Route Charts, DOD En route Charts, Chart 
Supplements, NOTAMs, and Track Messages. 

OCEANIC TRANSITION ROUTE

−

 An ATS route 

established for the purpose of transitioning aircraft 
to/from an organized track system. 

ODP

−

 

(See OBSTACLE DEPARTURE PROCEDURE.

)

 

OFF COURSE

−

 A term used to describe a situation 

where an aircraft has reported a position fix or is 
observed on radar at a point not on the ATC-approved 
route of flight. 

OFF

−

ROUTE OBSTRUCTION CLEARANCE AL-

TITUDE (OROCA)

−

 A published altitude which 

provides terrain and obstruction clearance with a 
1,000 foot buffer in non

−

mountainous areas and a 

2,000 foot buffer in designated mountainous areas 
within the United States, and a 3,000 foot buffer 
outside the US ADIZ. These altitudes are not 
assessed for NAVAID signal coverage, air traffic 
control surveillance, or communications coverage, 
and are published for general situational awareness, 
flight planning, and in

−

flight contingency use. 

OFF-ROUTE VECTOR

−

 A vector by ATC which 

takes an aircraft off a previously assigned route. 
Altitudes assigned by ATC during such vectors 
provide required obstacle clearance. 

OFFSET PARALLEL RUNWAYS

−

 Staggered 

runways having centerlines which are parallel. 

OFFSHORE/CONTROL AIRSPACE AREA

−

 That 

portion of airspace between the U.S. 12 NM limit and 
the oceanic CTA/FIR boundary within which air 
traffic control is exercised. These areas are 
established to provide air traffic control services. 
Offshore/Control Airspace Areas may be classified 
as either Class A airspace or Class E airspace. 

OFT

−

 

(See OUTER FIX TIME.) 

OM

−

 

(See OUTER MARKER.) 

ON COURSE

−

 

a. 

Used to indicate that an aircraft is established on 

the route centerline. 

b. 

Used by ATC to advise a pilot making a radar 

approach that his/her aircraft is lined up on the final 
approach course. 

(See ON-COURSE INDICATION.) 

ON-COURSE INDICATION

−

 An indication on an 

instrument, which provides the pilot a visual means 
of determining that the aircraft is located on the 
centerline of a given navigational track, or an 
indication on a radar scope that an aircraft is on a 
given track. 

ONE-MINUTE WEATHER

−

 The most recent one 

minute updated weather broadcast received by a pilot 
from an uncontrolled airport ASOS/AWOS. 

ONER

−

 

(See OCEANIC NAVIGATIONAL ERROR 

REPORT.) 

OPEN LOOP CLEARANCE

−

 Provides a lateral 

vector solution that does not include a return to route 
point. 

OPERATIONAL

−

 

(See DUE REGARD.) 

OPERATIONS SPECIFICATIONS [ICAO]

−

 The 

authorizations, conditions and limitations associated 
with the air operator certificate and subject to the 
conditions in the operations manual. 

OPPOSITE DIRECTION AIRCRAFT

−

 Aircraft are 

operating in opposite directions when: 

a. 

They are following the same track in reciprocal 

directions; or 

b. 

Their tracks are parallel and the aircraft are 

flying in reciprocal directions; or 

c. 

Their tracks intersect at an angle of more than 

135

. 

OPTION APPROACH

−

 An approach requested and 

conducted by a pilot which will result in either a 
touch-and-go, missed approach, low approach, 
stop-and-go, or full stop landing. Pilots should advise 
ATC if they decide to remain on the runway, of any 

PCG O

−

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