[VAC] Re: 40's Pipe Frame models

["Fred Coldwell" <Agrijeep@xxxxxxxxx>]

Hi Charlotte:

   "Pipe frame" Airstream trailers were built from 1947 to
1949/50, and usually have both or one end rounded (like
french bread loaf round) with a single wide oval window on
that rounded end.  The trailers back then were built very
light with few appliances and furnishings, so their frame
could be relatively lightweight.  The pipe frame was
strengthened slightly in 1949 by adding another 3' section
of
pipe inside the front most 3 feet near the hitch.  But the
frame soon became insufficient for the added weight of
larger trailers with more stuff installed and loaded
inside.   

    The "pipe frame" was called a centerpole by Airstream. 
The frame is like a fish skeleton: a longitudinal center rib
with outriggers to both sides.  The outriggers are not all
that strong and cannot take too much weight being placed on
them (other than above and immediately inside the wheels,
which area has some additional framing).  You will typically
see the appliances mounted in the center of trailers,
usually above or just forward of the wheels, as that is best
for weight distribution. 

    The first ladder frame Airstream with a "A" frame up
front appeared in mid 1949.  It was the 24' "Unlimited",
soon to be renamed the "Cruiser."  By 1950, all new
Airstream trailers were built using the ladder frame. 

     The pipe frames are still OK if not rusted inside the
tube, if the trailer is kept light and not overloaded, and
if you avoid using weight equalizing bars (which will
overpower the weaker-than-ladder-frame design).  The 1947 &
48 pipe frames are the weakest, the 1949s are slightly
stronger.  But none of them compare in strength to the
ladder frames that followed.  

     Bud Cooper restored his 1947 Airstream 22' Liner on a
brand new ladder frame made of 6 inch channel.  That is an
excellent foundation for an old trailer than is intended to
be used extensively.  

Fred Coldwell
VAC Archive Historian