Re: teeny vertical fins

Date:         19 Feb 97 02:46:22 
From: (Scott Miloro)
Organization: University at Buffalo
References:   1 2
Followups:    1
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In article <airliners.1997.434@ohare.Chicago.COM>, (Edward Hahn) writes...
>In article <airliners.1997.384@ohare.Chicago.COM>, (Scott
>Miloro) wrote:

>You could be seeing VHF blade antennas.  These are small (about a foot or so
>in length) and hang from the VENTRAL side  (underside) of the fuselage.

Many folks have followed up by mail, and none of them mention the ventral
side.  You could probably visit any number of photo archives to see the
dorsal VHF blade antennae.  That said, I have also seen the ventral-side
structures.  My guess is that you are correct that they, too, are blade
antennae.  Speaking to the cases of B747-200 and 757, I have only seen the
dorsal blade antennae - I will have a look at pics to see for myself (too
lazy to go out to Logan.)  Any guess as to possible advantages/disadvantages
to the ventral placement of blade antennae?  I think that on smaller a/c
designers might worry about some lummox tweaking one, but who knows.

>As for a "dorsal" fin, B737s have it - it is the extension of the leading edge
>of the vertical stabilizer forward along the fuselage.

That is to say, the leading edge of the vstab = a big blade antenna?

Scott Miloro, Dept of Human Genetics
Genome Therapeutics Corp, Waltham, MA, USA