A Glossary for the Perplexed

Here's an explanation of some of the more technical terms contained in my odyssey. While pilots may cringe when reading some of my definitions, hopefully they'll get the idea across.

0-0 Takeoff: Taking off while under the hood.

1000, etc.: Numbers expressed in thousands usually refer to feet of altitude.

AIRMET: Announcement of weather conditions that will effect small aircraft.

Actual: Flying in actual instrument weather conditions, in contrast to simulated instrument conditions (see 'hood')

AGL: Distance Above Ground Level, usually expressed in feet.

AI: Attitude Indicator; an instrument that provides an 'artificial horizon' display, permitting the pilot to keep the airplane right side up when the 'real' horizon is not visible due to weather (or wearing a hood)

Approach: 1)A documented series of turns and altitude changes intended to align a landing airplane with the runway when weather conditions prevent this from being done visually. Various types of approaches offer different degrees of accuracy. Some approaches depend upon timing portions of the flight with a stopwatch. 2) When preceeded by a geographical name (eg. New York Approach), refers to the radio call sign of air traffic control for that area.

ATIS: A recorded announcement played over the radio to advise pilots of airport conditions, weather, runway(s) in use, etc. (stands for Automatic Terminal Information System, if you care.)

ATP: Airline Transport Pilot - Those guy (and gals) in the front of 747s.

Base:The part of a landing when the airplane is at right angles to the runway. It will turn once and then be lined up for landing.

Behind the plane:That sad state of affairs when things are happening faster than you can cope with them, and undone tasks are accumulating. Not healthy when you're the PIC.

Broken: Refers to a layer of clouds that is blocking more than half the sky.

CFII: Certified Flight Instructor, Instrument.

Circle to Land: Not all approaches end neatly lined up with a runway. Some just get you to the airport, but not necessarily lined up with the runway. If you fly one of these, you have to circle a bit, in order to land.

DG: Directional Gyro; a gyroscopic compass that's better than the 'real' magnetic one for several reasons I'm not going to get into here. Unfortunately, it tends to drift with time, so it must be regularly be reset to match the magnetic one.

Downwind: 1)Moving in the same direction as the wind. 2)The part of a landing when the airplane is parallel to the runway. The airplane will turn twice and then be lined up for landing.

Fail (verb): To simulate the failure of an instrument (usually by covering it up).

FARs: Federal Aviation Regulations. These are the rules, but they are written in legalese, making them somewhat resistant to understanding.

Final: The part of a landing when the airplane is lined up with the runway, ready to land.

FBO: Fixed-Base Operator - A (usually) privately-owned business at the airport where you can park you plane, get it fixed, buy gas or flying lessons, etc.

FPM: Feet Per Minute - How fast your're going up or down.

GA: General Aviation. You know, the little airplanes that don't say 'AMERICAN' on the side.

Glide Slope: The part of the ILS that provides vertical information.

Hold: A manuever for "holding" the plane at a particular location by flying a series of racetrack-like ovals. Wind can complicate this somewhat. These are used by air traffic control to space aircraft, or can be used by pilots (with permission) to wait out weather, take time to prepare for an approach, etc.

Hood: A hat-like contrivance with a long bill that hangs over a pilot's face to obstruct his view out the window, simulating IFR conditions.

IFR: Instrument Flight Rules. The rules that apply when weather is poor enough to provide adequate visibility for flight. The expression is sometimes used to refer to that weather.

ILS: Instrument Landing System. A navigation system used to permit very precise landings in poor visibility. A pair of radio transmitters provide both vertical and horizontal information, allowing the pilot to precisely control the airplane without visual reference until it is as little as 200 ft from the ground. When properly done, this is seriously neat!

IMC: Instrument Meteriological Conditions - Weather that requires flight by instruments.

In the soup: Slang for flying with no visibility because of weather. (see 'actual')

Jepp: Short for Jeppesen, a publisher of aviation charts. 'Jepp' charts are more expensive, but generally thought to be superior to, the ones published by the government.

Localizer: The part of the ILS that provides horizontal information.

MDA: Minimum Descent Altitude: During an instrument approach, this is how far down you're permitted to go before seeing the airport. If you go lower, you risk bumping into something (like the ground!)

Missed Approach (or 'missed'): A documented series of climbs and turns; part of every Approach. If, after flying the approach, you don't see the airport, you fly the Missed Approach to take you safely away from the ground and to a known location so you can decide what to do next.

NBD: Non-Directional Beacon. A radio transmitter used for navigation. A companion receiver in the airplane provides a pointer that points at the station. This can be confusing, because as the plane turns, so does the pointer. The NDB receiver can also be tuned to standard AM broadcast radio stations.

Overcast:A solid layer of clouds too thick to see through.

Partial Panel: Simulating the failure of one or more instruments, usually by covering them up. This is an exercise, practicing for if the instruments actually fail in flight.

PIC: 1) Abbreviation for Pilot-In-Command; the individual taking responsibility for the flight. 2) The name of a generally well-respected instrument trainingschool.

PIREP: Pilot Report: These are weather and other observations radioed by pilots to Flight Service, where they are made available to other pilots.

PPL: Private Pilot License - usually implying no instrument rating.

Procedure Turn: A maneuver for executing a 180 degree turn at a particular location using a compass and a radionavigation aid. Drawn on a piece of paper, it looks vaguely like those "teacup handle" exits on New Jersey highways.

Scattered: Refers to a layer of clouds that is blocking less than half the sky.

Avsigger: Not really an airplane term - in this context refers to a regular contributor or reader to Compuserve's AVSIG aviation forum

Squalk VFR: Setting the aircraft radar transponder to the position reserved for VFR flight without monitoring by air traffic control.

TCA: Terminal Control Area - that area surrounding a big airport, which aircraft must not enter without permission. Has recently been renamed 'Class B Airspace' in accordance with international regulations.

Track: To fly the plane over a straight line to or from a specific location. This can be complicated by winds, compass and arithmetic errors, etc.

Transponder: A radio transmitter in the plane that responds to the radar signal from Air Traffic Control, permitting it to easily detect the airplane. The transponder it set to a "squalk code" to permit the aircraft to be identified. The transponder also reports the airplane's altitude.

Vector: A turn to a particular compass direction requested of an aircraft by Air Traffic Control, usually to direct it toward its destination.

VFR: Visual Flight Rules. The rules that apply when weather provides good visibility. The expression is sometimes used to refer to that weather.

VOR: VHF Omni-Range. A radio transmitter used for navigation. A companion receiver in the airplane provides an indicator that shows the direction from the station to the airplane. This is somewhat simpler to use than an NDB because the indication is independent of which way the airplane is pointed or moving.

VASI: A pair of lights adjacent to the runway that indicate to the pilot whether his approach is too high, too low, or just right.

VSI: Vertical Speed Indicator; tells how fast your're going up or down.

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