Re: where is radio antenna

From: (Ed Hahn)
Organization: The MITRE Corporation, McLean, Va.
Date:         01 Sep 94 01:14:47 
References:   1
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In article <airliners.1994.1550@ohare.Chicago.COM> (John Oliver) writes:

   Can anyone tell me where the radio antennae are located on jumbo jets? I
   assume they are not inside the metal hull since an electromagnetic field can
   not penetrate a metallic conductor.

   John Oliver
Radio antennas are generally located on the bottom of the
fuselage.  The ~12in long, 2in wide, angled antennas are VHF; the
little 4in by 2in antennas are microwave (transponders, DMEs).  There
are also conformal "patch" antennas for the radio altimeters.

HF, satellite, GPS, and upper TCAS antennas are located in various
other places.  On B747s PRIOR to the -400, they were the big "stinger" on
the right wingtip facing backwards.  On aircraft like the B707 and
B727, they are located on the tip of the tail (the B727 HF antenna is
mostly buried in the fin tip fairing).  SATCOM antennas are generally
located on the top of the fuselage, and look like "humps" about 3 feet
long, 12 in wide, and 8 in high.  The hump is actually a fairing for a
steerable high-gain unit (mechanical or phased-array).  GPS and TCAS
antennas are generally ~1in thick ellipsoidal plates, about 10in by
5in or so, mounted on the top of the fuselage. 

Of course, details vary from vendor to vendor, and so do appearances.

BTW, insects have antennae, aircraft have antennas. (At least in the
US.  Your language may vary.)


////////   Ed Hahn | | (703) 883-5988   \\\\\\\\
The above comment reflects the opinions of the author, and does not
constitute endorsement or implied warranty by the MITRE Corporation.
Really, I wouldn't kid you about a thing like this.