I've come across "L.W. and P.F. being used in counter mortar role" these being used in place of GL radar. Any suggestions?
LW In anti-aircraft terms was Local Warning. PF is most probably Position Finding. Always happy to help with gunner abbreviations, or you could buy the book !!!!
Thanks Philip! The question now, is what are these? They would appear to be small as a discussion in the diaries indicates that they could be taken into forward position when the AA was being used in a field role in Italy in 1944 where a GL unit would be precluded because it would be visible. Anyone any suggestions?
Local Warning was a radar set used, as the name implies to warn of aircraft in the immediate vicinity. PF will need some more investigation, as Position Finding is usually associated with Coast Artillery
Hi, I have the War Diary for 10th Indian Division Counter Mortar Org. I will see if I can find anything in the Diaries. Happy to let you have copies via dropbox. Just send me a PM with your e-mail address if you want them. Diane
LW is variously defined as 'local warning' or 'light warning' in the RA staff history and is identified as the Set AA No.4 Mk II or Mk III. Its CM purpose was for 'putting on' the GL III - LW had much wider coverage and could provide an approximate direction for the narrower-beamed GL III. PF isn't defined or indexed, though.
The staff history "Army Radar" casts another vote for LW = Light Warning [Equipment] Still no PF, but it does define APF as Accurate Position Finder (Canadian). This was the fire control element of the independently-developed-and-produced Canadian GL III(C) or, in British service the GL III Mk I. The other half of the story was the ZPI - Zone Position Indicator which was the local warning search set. ZPI and APF were separate trailer-mounted equipments. The APF in isolation was the slightly inferior equivalent of the British GL III Mk II (which did not include a dedicated LW set). If they are being used 'in place' of 'GL radar', perhaps 'LW and PF' is a mangled reference to the Canadian version's ZPI and APF? It would make some sense to have used the inferior Canadian kit for counter-mortar duties if the British version was preferred for gun control.
Interesting stuff, Idler, and thank you for the information. The reference to these two arose in a diary of the 76th HAA Regt after the Regt was converted to a field role, and the batteries were located on the Pisa plain in very exposed positions. It was recognised that a GL unit would be difficult to conceal in such locations, these as a result being located further back near the HQs to minimise the chance of them being spotted. The 'LW and PF' seem to have been introduced in the GL's place, and are referred to as being used,on an experimental basis initially, in a counter mortar role. The definitions of Local/Light Warning, and Position Finder seem to fit: it would be interesting, though, to know what these looked like.
Embarrassingly, The GL III variants are on Wiki! https://en.wikipedia.org/wiki/GL_Mk._III_radar The LW was a much handier set as it appears to have been fitted in a variety of truck bodies, e.g. See Section 3 Its small size ought to have been a benefit in the situation you've described.
Thanks Idler, more info for the book . Regarding PF it seems to have been used as an "alternative" reference to the Height an Rangefinder.
Incidentally, my definition of LW comes from the relevant Artillery Training pamphlets, however, the different definitions are not a surprise, as alternative meanings are regularly found in the same documents.
