[Scan-DC] variety of questions

[Gary Chatters]

>
>2) What does ARTCC stand for?

Air Route Traffic Control Center

>
>3) What does ATIS stand for?

Automatic Termainal Information Service

This is a recorded announcement that runs continuously on a 
dedicated avaiation channel.  Airports with a control tower
will each have their own ATIS channel.  The recording provides
weather, including cloud cover, winds and altimeter setting.
It also provides arrival information such as runway in use.
Each recording is identified by a sequence letter.  Arriving
pilots listen to the ATIS, then when contacted approach control,
state, for example, that they "have information alpha".

>
>4) What does Unicom mean?

This is a set of frequencies used for communications in the area
of an airport.  An airport may be assigned one Unicom frequeny.
At an uncontrolled airport it is used for traffic information.
Each arriving or departing aircraft announces its position and intentions
and listens for other aircraft.  At least one FBO will have a ground
station on the Unicom frequency.  Arriving aircraft can call for
airport information.  At controlled airports it is just for 
pilots to talk to the FBO.

>
>5) Is "Metro Traffic Control (450.9125 and others)"
>the WMATA Metro system?
>
>6) What is the best way to listen to the weather on a
>scanner in the DC area? Any special alert channels,
>too?

Continuous NOAA weather broadcasts can be heard in this area
on these channels:

162.400 Baltimore
162.550 Manassas
162.500 Sudlersville (Eastern shore)

Special alerts are on these same channels preceded by a 
digital code to turn on receivers with alerting capability.

gc