[MilCom] E-4B departure

[AllanStern at aol.com]

_baycomm at earthlink.net_ (mailto:baycomm at earthlink.net)   writes:
>
> Most 747's have a apu back there, sure one circle is not  that?

 
I believe you are right,  Greg.
One of the circles is the 5-mile long TWA (Trailing Wire Antenna) that is  
on a hydraulic winch, and is used for VLF comms.  I believe that at one  
time, the aircraft also had a shorter TWA it could deploy, but that might have  
gone away with the advent on comms systems improvements.
 
AL STERN  Satellite Beach  FL
AllanStern at aol.com
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