Search This Blog

Presidential Aircraft Communications - Echo-Fox Radio Network

 

 The Echo-Fox Radio Network

   Air Force One SAM 26000 Radio Console

Type of Activity

Air Transport

Location

Location

Worldwide

Date of Activity

Oct 1962 to  June 2001

Coordinates

33°40′34″N 117°43′52″W

The UHF  system WHCA operated (on 415.7/407.85) is code named "Echo Foxtrot", or "Nationwide" (the later name distinguishes it from the "Washington Area" system used for communications with White House limos and staff cars). It provides full duplex clear voice coverage over most of the continental US to VIP aircraft in flight (SAM aircraft - Special Air Missions - which fly out of Andrews AFB). It links them to a console Crown Radio  at the White House Switchboard ("Crown") in the Old Executive Office building basement from which phone patch connections can be made to telephones at the White House, on the commercial POTS/DDD network, various other federal telephone systems, and occasionally the DSN (Defense Switched Network - formally Autovon). 

White House Signal Switchboard ("Crown")

Crown Radio had two consoles one was the Washington DC FM network. The other one was for the Nationwide System (E/F), and secure voice. All of WHCA and USSS FM locations in the Washington DC area terminated there, as well as the Echo/Fox Nationwide air-to-ground Communications for AF1. The old E/F console built by Mario Lilla was operated from WHCA's M St location until Crown Radio was moved to the OEOB shortly after the new WECO 608 was cut into service there. Crown Radio (CR) went operational for the first time in the mid-sixties. At the time CR was that it only controlled the E/F network CR was manned and operational only in support of a POTUS mission. The only radio phone patches from CR was to WH Signal board who handled connections to telephone subscribers, and CR only operated the air-to-ground E/F network.

Crown Radio the E/F radio Console

The system is operated by the White House Communications Agency (WHCA), and AT&T. Ground sites (there are about 30 of them) for the E/F system are located on AT&T microwave towers throughout the US and are connected by leased lines to a tech control console ("Crown Radio") that is part of the White House Switchboard ("Crown" or "Signal"). Each individual site can be separately keyed from the console and patched into a call, thus the system is capable of handling several calls at once although the aircraft involved have to be far enough apart not to interfere with one another. 

The E/F system is completely manual at both ends, call setup and ground site selection is done by operators. On the ground the operators are WHCA/White House switchboard operators, on the aircraft they are CSO (Communication System Officers) who are military NCO's (tech sergeants mostly).

The E/F system is in-the-clear UHF full duplex voice. The aircraft often push-to-talk keys its transmitter, so it only transmits when the party on board is talking. The ground site usually transmits continuously for the duration of the call. 

The system has been recently used with STU-III's for security, but apparently not too successfully. There have been occasional attempts in the past to use other kinds of secure voice, but most calls are still in the clear. Recent White House staff people who use the system have been made aware that listening to it is quite popular among scanner hobbyists and have been fairly careful about what they say, but when the system was first installed in the late 60's and early 70's there were some interesting conversations on it.

E/F antennas on AT&T towers are small and not very conspicuous but they can be recognized if one knows what they look like. They are always mounted at the top of the tower near the Hogg horns. There are usually three antennas, two small ground planes and a short vertical pole mounted above them and three or four feet apart.

Air Force One mostly uses the E/F system for actual phone connections when it is out of range of other systems or there is extremely heavy traffic on them (but it always maintains contact via E/F when in range of a ground site as backup anyway) and has in the past sometimes used E/F as a communications order wire to set up calls on the other systems. 

Echo-Fox antenna cluster atop an AT&T tower
Image courtesy of Tim Tyler; photographed May 25, 2002.

Note: Echo-Fox is no longer in service; it is reported to have been shut down in 1996.

Coverage Map

 This green-shaded area on this map shows the estimated coverage of the Echo-Fox stations listed in the table above (indicated by black dots), assuming a 200-mile range for each transmitter:

Echo Fox Nationwide Network

Echo-Fox Radio Sites as of March 1973

AT&T Corporate Security has requested that the names and exact locations of certain active facilities not be published; therefore, such installations are identified only by their Common Language Location identifier (CLLI) codes, printed in all capitals.

State

Station

Owner

Control Office

Alabama

Brewton

     Long Lines

ARTNVACKT20

Arizona

Holbrook

     Mountain Bell

WASHDCDTW20

Arizona

Seligman

     Long Lines

ARTNVACKT20

Arkansas

Memphis Junction

     Long Lines

ARTNVACKT20

California

Mount Wilson

     Pacific Tel. & Tel.

ARTNVACKT20

California

Stockton

     Pacific Tel. & Tel.

ARTNVACKT20

California

Turquoise Junction

     Pacific Tel. & Tel.

WASHDCDTW20

Colorado

Prospect Valley

     Long Lines

ARTNVACKT20

Florida

Daytona Beach

    Southern Bell Tel. & Tel.

ARTNVACKT20

Florida

Perrine

    Southern Bell Tel. & Tel.

WASHDCDTW20

Georgia

Adairsville

     Long Lines

WASHDCDTW20

Idaho

Boise Junction

     Long Lines

ARTNVACKT20

Illinois

NRWYILNO

     Long Lines

WASHDCDTW20

Iowa

Red Oak

     Long Lines

ARTNVACKT20

Kansas

Hays

     Southwestern Bell

WASHDCDTW20

Kentucky

WLTWKY01ZAZ

     Long Lines

ARTNVACKT20

Louisiana

Alexandria

     South Central Bell

WASHDCDTW20

Maine

Portland

     New England Tel. & Tel.

WASHDCDTW20

Maryland

WDRFMDQO

     Long Lines

WASHDCDTW20

Minnesota

Minneapolis

     Long Lines

WASHDCDTW20

Missouri

Hillsboro

     Long Lines

ARTNVACKT20

Montana

Helena Junction

     Long Lines

ARTNVACKT20

Montana

Miles City

     Mountain Bell

WASHDCDTW20

New Mexico

Clines Corner

     Long Lines

ARTNVACKT20

Nevada

Winnemucca

     Bell Telephone of Nevada

WASHDCDTW20

New York

New York City

     Long Lines

ARTNVACKT20

North Carolina

Westover

     Long Lines

ARTNVACKT20

Ohio

Navarre

     Long Lines

ARTNVACKT20

Oklahoma

Mounds

     Long Lines

WASHDCDTW20

Oregon

Mount Baldy

     Pacific Northwest Bell

WASHDCDTW20

South Carolina

Charleston

     Southern Bell Tel. & Tel.

WASHDCDTW20

South Dakota

Chamberlain

     Northwestern Bell

ARTNVACKT20

Texas

Amarillo Junction

     Long Lines

WASHDCDTW20

Texas

Ennis

     Long Lines

ARTNVACKT20

Texas

Midland

     Southwestern bell

ARTNVACKT20

Texas

Seguin

     Long Lines

WASHDCDTW20

Utah

Crescent Junction

     Long Lines

WASHDCDTW20

Utah

Levan

     Long Lines

ARTNVACKT20

Washington

Seattle No. 5

     Pacific Northwest Bell

ARTNVACKT20

Washington

Spokane

     Pacific Northwest Bell

WASHDCDTW20

Wyoming

Rock Springs

     Mountain Bell

WASHDCDTW20


Adapted from Bell System Practice 406-116-100, Issue 2, March 1973, pp. 6-7, table A
 

 

No comments:

Post a Comment