For those who monitor military radio traffic, today has been an extraordinary deviation from the norm.  "SKYKING" has been broadcasting Emergency Action Messages all day and, for some reason have been repeating particular messages at :10 and :40 after each hour!

In addition, two Boeing E4-B "Doomsday" planes have been in the air all day on Automatic Dependent Surveillance-Broadcast (ADS-B).  Something is happening.

The Boeing E-4 Advanced Airborne Command Post, with the project name "Nightwatch" is a strategic command and control military aircraft operated by the United States Air Force (USAF).

The E-4 series was specially modified from the Boeing 747-200B for the National Emergency Airborne Command Post (NEACP) program.

The E-4 serves as a survivable mobile command post for the National Command Authority, namely the President of the United States, the Secretary of Defense, and successors.

There are only four E-4Bs and they are operated by the 1st Airborne Command and Control Squadron of the 595th Command and Control Group located at Offutt Air Force Base, near Omaha, Nebraska. An E-4B when in action is denoted a "National Airborne Operations Center."



The High Frequency Global Communications System (HFGCS) is a network of single sideband shortwave transmitters of the United States Air Force which is used to communicate with aircraft in flight, ground stations and some United States Navy surface assets.

All worldwide receiving and transmitting sites in the HFGCS system are remotely controlled from Andrews Air Force Base and Grand Forks Air Force Base. Before 1 October 2002 it was known as the Global High Frequency System(GHFS).

HFGCS stations tend to operate in the aviation bands clustered around 5, 8 and 11/12 MHz, although other frequencies are in use.

The primary HFGCS voice frequencies are 4724.0 kHz, 6739.0 kHz, 8992.0 kHz, 11175.0 kHz, 13200.0 kHz and 15016.0 kHz. In addition to the HFGCS, U.S. aircraft frequently use Military Affiliate Radio System (MARS) HF stations (13927.0 kHz) and Canadian Forces HF stations (11232.0 kHz) to relay messages.


One common use for the HFGCS is to place telephone calls from the aircraft in flight by means of the Defense Switched Network (DSN) to an Air Force base to obtain local weather conditions, to arrange for refueling, and to inform the base of the number of passengers and crew. The HFGCS also carries Emergency Action Messages.

In addition to EAM's the HFGCS also carries a few different types of messages. A higher priority code for orders is a Skyking Message, which is a time sensitive message for orders that need immediate attention. Force Direction Messages (FDM's) are also sent through the HFGCS, although it is impossible to tell whether the message is an FDM or just another EAM being read. The sign off 'Color Bar' is currently being used (2016) at the end of the transmission.

During the course of Monday (March 5) numerous "Skyking" messages were being broadcast. The shear quantity of EAM's was very unusual. 

All such messages are encrypted insofar as the message contains a series of letters and numbers whose meaning cannot be discerned without a Code Book, which is a Top Secret military manual unavailable to the public.

Since EAM's and Skyking Messages are High Priority requiring immediate attention, this sudden surge in such messages seems a bit ominous.

While there is no way for us to decipher the content of the messages, their existence indicates "something's up."