Pilot/Controller Glossary

4/3/14

PCG M−2

imminent and grave danger and that immediate

assistance is requested.

 (See PAN-PAN.)
 (Refer to AIM.)

MCA−

(See MINIMUM CROSSING ALTITUDE.)

MDA−

(See MINIMUM DESCENT ALTITUDE.)

MEA−

(See MINIMUM EN ROUTE IFR ALTITUDE.)

MEARTS−

(See MICRO-EN ROUTE AUTOMATED RADAR

TRACKING SYSTEM.)

METEOROLOGICAL IMPACT STATEMENT−

An unscheduled planning forecast describing

conditions expected to begin within 4 to 12 hours

which may impact the flow of air traffic in a specific

center’s (ARTCC) area.
METER FIX ARC− A semicircle, equidistant from

a meter fix, usually in low altitude relatively close to

the meter fix, used to help CTAS/HOST calculate a

meter time, and determine appropriate sector meter

list assignments for aircraft not on an established

arrival route or assigned a meter fix.
METER FIX TIME/SLOT TIME− A calculated time

to depart the meter fix in order to cross the vertex at

the ACLT. This time reflects descent speed

adjustment and any applicable time that must be

absorbed prior to crossing the meter fix.
METER LIST−

(See ARRIVAL SECTOR ADVISORY LIST.)

METER LIST DISPLAY INTERVAL− A dynamic

parameter which controls the number of minutes

prior to the flight plan calculated time of arrival at the

meter fix for each aircraft, at which time the TCLT is

frozen and becomes an ACLT; i.e., the VTA is

updated and consequently the TCLT modified as

appropriate until frozen at which time updating is

suspended and an ACLT is assigned. When frozen,

the flight entry is inserted into the arrival sector’s

meter list for display on the sector PVD/MDM.

MLDI is used if filed true airspeed is less than or

equal to freeze speed parameters (FSPD).
METERING− A method of time-regulating arrival

traffic flow into a terminal area so as not to exceed a

predetermined terminal acceptance rate.

METERING AIRPORTS− Airports adapted for

metering and for which optimum flight paths are

defined. A maximum of 15 airports may be adapted.
METERING FIX− A fix along an established route

from over which aircraft will be metered prior to

entering terminal airspace. Normally, this fix should

be established at a distance from the airport which

will facilitate a profile descent 10,000 feet above

airport elevation (AAE) or above.
METERING POSITION(S)− Adapted  PVDs/

MDMs and associated “D” positions eligible for

display of a metering position list. A maximum of

four PVDs/MDMs may be adapted.
METERING POSITION LIST− An ordered list of

data on arrivals for a selected metering airport

displayed on a metering position PVD/MDM.
MFT−

(See METER FIX TIME/SLOT TIME.)

MHA−

(See MINIMUM HOLDING ALTITUDE.)

MIA−

(See MINIMUM IFR ALTITUDES.)

MICROBURST− A small downburst with outbursts

of damaging winds extending 2.5 miles or less. In

spite of its small horizontal scale, an intense

microburst could induce wind speeds as high as 150

knots

(Refer to AIM.)

MICRO-EN ROUTE AUTOMATED RADAR

TRACKING SYSTEM (MEARTS)− An automated

radar and radar beacon tracking system capable of

employing both short-range (ASR) and long-range

(ARSR) radars. This microcomputer driven system

provides improved tracking, continuous data record-

ing, and use of full digital radar displays.
MICROWAVE LANDING SYSTEM− A precision

instrument approach system operating in the

microwave spectrum which normally consists of the

following components:

a.

Azimuth Station.

b.

Elevation Station.

c.

Precision Distance Measuring Equipment.

(See MLS CATEGORIES.)

MID RVR−

(See VISIBILITY.)

MIDDLE COMPASS LOCATOR−

(See COMPASS LOCATOR.)