Acronym Challenge

There's two very obscure British Army acronyms that I'm trying to get to the bottom of, but have had no luck so far.

The first is the PLM mounting, which was a twin or single AA mounting fitted to tanks or armoured cars, and whose initials I have never seen explained. I suspect it might stand for Parallel Light Mounting, but can anyone confirm?

The second is SMS, which was a process by which vehicles were modified in service. I think this stands for Stores Management System, but again can anyone confirm?

Thanks in advance...

 

Hi, PLM,,,,,, I think it could mean Projectile Location Mechanism.
Still working on SMS

David

 

Hi, SMS,,,,,, I think it could mean Special Mechanical System.
Hope it helps

David

 

Whoops - please delete

 

From http://www.warwheels.net/BritishArmouredCarProductionFiguresArticleBROWN.html The P.L.M. Mounting was the Parrish-Lakeman Mounting which was used as a AA mounting with twin Vickers GO guns on some tanks but on the Humber carried a single Bren with the 100 round drum original designed for antiaircraft use. It could be operated from inside the vehicle to elevate, traverse and fire. On later vehicles without a roof, the Bren would have to be carried loose.

If you Google Parrish Lakeman you'll get a few hits. The Lakeman part must refer to Thomas Lakeman, who designed some pretty Heath Robinson devices for mountinmg machine guns which were universally deplored - Mr(?) Parrish must have brought some design sense to the team.

From:http://www.o5m6.de/bren_gun_lakeman.html

"According to Mr.David Fletcher from the Bovington Tank Museum, Tom Lakeman, the designer of the AA mount installed on numerous British tanks of the early war years, was a Royal Tank Regiment officer, slightly mad according to people who knew him, who devised all kinds of strange machine-gun mountings.
The principle was a balance of arms and springs, like an office desk lamp, the idea being to reduce the weight of the weapon when used against aircraft. In practice they were usually more trouble than they were worth and most soldiers hated them and tried to throw them away at the first opportunity."

 

Wow, thanks Brian for the info, just did not Google enough.........

 

Thanks Brian - that's brilliant. Parrish-Lakeman would make sense, as the original Lakeman Bren mounting was a single AA Bren mount for AFV's.

SMS was a kind of retrospective action to modify tanks and vehicles that were already in service i.e. if it was too late to include a modification in production, but it was nevertheless really important, it would be implemented by "SMS action". So the initials of SMS must stand for some kind of in-service modification, probably carried out by the REME.

 

I was avoiding doing proper work, so developed a sudden persistence - quite uncharacateristic I assure you. But I had heard of Lakeman when doing some research at Bovington (and wandered off the subject as usual) - He was RTR and came up with some real Heath Robinson stuff for tanks - as it says above, looked like desk lamps...

 

I fully understand where your coming from Brian (avoiding the housework, washing up ect).
I'm Learning all the time on the forum
Still working on SMS Don Juan

David

 

I even managed to edit my post and not correct the spelling mistake....

 

OK - I can confirm SMS stands for Service Modification Schedule.

This was submitted by Tank/Vehicle manufacturers to the REME instructing them what modifications needed to be enacted on service vehicles.

 

In the onion bag! A brace - not often that happens.

 

Thanks Don Juan for the update


David

 

OK, it seems that PLM might not stand for Parrish-Lakeman Mounting. Below is an extract from Middle East AFV Technical Report No.12 of 31st January 1943.

It indicates that the PLM mounting was designed by Lewis Motley, who was the inventor of a number of paired Bren Mountings. There is an in-depth discussion of them on this Canadian thread:

Bren LMG mount - MLU FORUM

So my guess now is that PLM might have stood for Paired Lewis Motley, or something similar. So this is a bit of a mystery again...

 

I think this is the US patent of the PLM Mounting here.

Filed December 29th 1942. From the description, I would guess that the "P" stands for Pivoted.

So: Pivoted Lewis Motley mounting?

 

There's an eye-opening article on Lewis Motley here. One of his pastimes seems to have been inventing hand-held rocket guns! The article states that Motley worked for Hydran Products Ltd., but this (middle paragraph of the right hand column) indicates that he in fact owned the company.

One thing not mentioned so far, but which I can confirm from my own research, is that Hydran designed the first multi-barreled smoke launchers for AFV's, as fitted for example on the Comet tank.

 

It's nothing more than food for thought, but looking at this the other day P for protected and/or L for link(ed) might not be out of place for an under-armour system?

 

Yes, I think the "P" would most likely stand for "Protected" or "Protective", as the patent emphasizes that this was the whole point of the design. As Motley seems to have designed two versions of the mounting, one of which was for a Heavier gun, the "L" might stand for "Light". The "M" could stand for "Motley" or "Machine gun" or even "Mounting".

I have a suspicion that there wasn't a fixed definition of "PLM", which is why it doesn't ever appear to have been stated explicitly, and what it actually stood for probably differed depending on what mood Motley was in whenever someone asked him.

 

I have found evidence (see below) that Major Parrish of the Gunnery Wing at Lulworth WAS instrumental in the design of the PLM mounting. This was initially quite frustrating, as it cuts across the evidence that it was Lewis Motley who developed and patented it.

But then it occurred to me - what if Parrish and Lakeman designed it, or Parrish adapted it from the Lakeman mounting, and it was passed on to Motley for development and production? If that is the case, then the meaning of PLM becomes obvious -

It is the Parrish Lakeman Motley mounting.