[Milsurplus] WTF? Nomenclature style

[William Donzelli]

While going thru some manuals, looking for that AN/ARW set that uses the 
modified BC-454, I noticed something very confusing. Apparently the 
military could reuse numbers in the AN/ system. As many of you know, when 
a piece was in the developement stage, it would get an "X" number. For 
example, TS-XA-70/AP, The XA meant that the unit was sponsored by Wright 
Field, XN was the NRL, and so on.

It appears that those numbers are tentative, and could be reassigned, even
if hardware exists. Some of the goodies I recently obtained near Dayton,
with a tremendous quantity being XA developemental units, show this. 

In my manuals, I came across a blueprint for the R-(XA)-11/ARQ-5(XA-3C). 
This is a precusrsor to the standard issue R-61/ARQ-5. But, R-11/ is 
reused later for the R-11/CPN-3. This latter unit did go into full 
production. Additionally, I have a manual for the AN/ARQ-5(XA-4C) (the 
next try, I suppose), and the main unit is an R-(XA)-12/ARQ-5(XA-4C). 
Once again, R-12/ is "normally" used with the R-12/CPN-2.

To top it off, I dragged home a pair of RT-XA-17/AP units (I think they 
are spoofers). Real hardware, but RT-17/ was finally given to the 
AN/APS-6, as RT-17/APS-6. 

In all three cases it is clear that the X number and the final number 
could be completely different pieces of equipment. 
  
So, Robert, Mike, and the other nomenclature nuts, you have more to think 
about.

Also, in the pile I found a blueprint and some official looking docs for 
the PP-278(XA)/ART-13A - a replacement power unit for the dynamotor, 
using 3B28s. I wonder if any were made...

William Donzelli
aw288@osfn.org