Aeronautical Terms beginning with I

IAC

Interagency Air Committee

IACC

Interagency Air Cartographic Committee

IAF

Initial Approach Fix.

IAP

Instrument Approach Procedures.

IAS

Indicated Airspeed.

IATA

International Air Transport Association

IAWP

Initial Approach Waypoint

IC

Ice crystals, in-cloud lightning

ICA

Initial Climb Area

ICAO

International Civil Aviation Organization.

ICR

Integrated collaborative rerouting (ICR) is a process that builds on FEA/FCAs. The ICR process requires that a constraint is identified early. Traffic management may issue a planning (PLN) advisory describing the system constraint and providing route guidance. System stakeholders are allowed an opportunity to consider the area of concern, and provide early intent (EI) messages that communicate their decisions in response to the constraint. EI messages update enhanced traffic management system (ETMS) flight trajectories, monitor alert values and routing intentions. At the expiration of the EI window, traffic management can then analyze the customer responses and decide if the actions taken have resolved the issue, or if recommended routes, required routes, airspace flow programs (AFP) and/or other traffic management initiatives (TMIs) will be necessary to further reduce demand. ICR allows system stakeholders flexibility in managing their flights based on an identified NAS constraint, reducing the possibility of more restrictive initiatives. Traffic flow management (TFM) tools benefit from enhanced flight information and collaborative responses to system capacity actions.

IDT

Identifier

IF

Intermediate Fix

IF/IAWP

Intermediate Fix/Initial Approach Waypoint. The Waypoint Where The Final Approach Course Of A T-Approach Meets The Crossbar Of The T. When Designated (In Conjunction With A TAA) This Waypoint Will Be Used As An IAWP When Approaching The Airport From Certain Directions, And As An IFWP When Beginning The Approach From Another IAWP

IFP

Instrument Flight Procedure

IFR

Instrument Flight Rules.

IFSD

In-Flight Shutdown.

IFWP

Intermediate Fix Waypoint

IIMC

Inadvertent Instrument Meteorological Condition

ILS

Instrument Landing System.

ILS/PRM

Instrument Landing System/Precision Runway Monitor

IM

ILS Inner Marker.

IMC

Instrument Meteorological Conditions.

IMSAFE

An acronym that represents the six aeromedical risk areas: Illness, Medication, Stress, Alcohol, Fatigue, and Emotion.

in

inch

inHg

inches of mercury

INS

Inertial Navigation System.

INT

Intersection.

IR

IFR Military Training Route

IRS

Inertial Reference System

IRU

Inertial Reference Unit

ISA

International Standard Atmosphere

ITCZ

Intertropical Convergence Zone

ITWS

Integrated Terminal Weather System

IVSI

Instantaneous Vertical Speed Indicator.