Re: B757 "Heavy Jet"?

From:         amb@bronze.lcs.mit.edu (andrew m. boardman)
Organization: Quiche Eaters Anonymous
Date:         03 Jul 96 01:23:53 
References:   1 2
Next article
View raw article
  or MIME structure

Gary S. Moffitt <gsmoff@Mcs.Net> wrote:
>The term "heavy jet" is not strictly defined by wieght, is is a generic
>term used to define wide bodies in general, which the 757 is not.

This is incorrect; IIRC, the US definition is an aircraft with a gross
weight (MGTOW, I think) of 300,000+ lbs., while the ICAO definition
differs slightly and immaterially.

Although the idea was on the table, the B757 was not actually classed as
a "heavy".  Instead, exceptions specific to the B757 have been added all
over 7110.65 (FAA Order 7110.65, a.k.a. the "ATC Bible") -- in just about
every situation dealing with wake turbulence, "heavy jet" has been
changed to "heavy jet or B-757".  Thus, following aircraft still get
"heavy" seperation, although B757s get normal "large" category seperation
behind "heavies".  The difference may be immaterial, but than again, they
still get to go to DCA. :-)

Should anyone have interest, I keep a copy of 7110.65 (without diagrams,
though) at http://www.cs.columbia.edu/~amb/aviation/7110/index.html.
Most of the seperation stuff is in 3-10 and 5-5 (chapter-section).

Factoid of the week: Air Force One never gets called "heavy".  I guess
it's too undignified or something...

andrew