[Milsurplus] Last flight of the LBG

[D C Macdonald]

The one I bought for $5 had all the tubes in it.

Mac



----Original Message Follows----
From: Mike Morrow <kk5f at earthlink.net>
Reply-To: Mike Morrow <kk5f at earthlink.net>
To: milsurplus at mailman.qth.net
Subject: Re: [Milsurplus] Last flight of the LBG
Date: Mon, 4 Apr 2005 13:07:48 -0700 (PDT)

Mac wrote:

 >I can't swear it was Fair, but somewhere around
 >'54-'55 I bought an AN/APS-13 (I think it was)
 >from some outfit for $4.95.

Yes, I remember the "tail-end charley" phrase in the adds for these sets in 
the back of my Dad's 1950s "CQ" magazines.  I recall that they came without 
tubes, for about $2.  If they were going for $5, then they'd have been quite 
expensive...that would be about $40 in today's dollars.

 >It was described as some sort of IFF, ("tail end charley"?) from B-29.

It was a pulsed 420 mc radar designed to detect aircraft approaching from 
the rear.  It was installed on USAAF night fighters like the P-61 Black 
Widow, and I've heard, on other aircraft like some models of P-51.  I don't 
think it had bomber application.  When an object was detected. a bell and 
light energized in the cockpit.  The big problem was that as an active 
radar, its signal could be used to detect and track the aircraft carrying 
it.  I think all were ultimately withdrawn from service for this reason.

Four of these RT-34/APS-13 units were modified (for wider frequency range) 
and installed on each of the atomic bombs dropped on Japan.  They were part 
of the fusing system used to determine proximity to ground for an air-burst 
detonation.  Fusing was complete when at least two out of the four APS-13s 
signaled 1800 feet above ground.

Practically, it's useless, but historically and technically, it's a very 
interesting set.

73,
Mike / KK5F