Searchlight Division, A/A Corps

[Matt Dixon]

I am currently doing a project on men from my old school, one of whom was in the Searchlight Division, Anti Aircraft Corps. Can anyone tell me when this regiment was set up, and what their role was.....(I know it sounds obvious but other than Anti-Zeppelin cover, what else did they do?) Were they part of the Royal Flying Corps, or the Royal Artillery? Anything you have I would be delighted to know!

Thanking you in ignorance!

[Guest Pete Wood]

Matt, I have many books on the air defence of Britain, but I can't find a specific mention of the "Searchlight Division." Sorry.

I can tell you that up until early 1916, the anti aircraft guns and lights were manned by members of the RNVR (under orders of the admiralty). These men were mainly former policemen and factory workers (from Woolwich etc). Former petty officers were recalled to give some military experience and substance to the anti aircraft guns and searchlights.

Each searchlight was manned by 6 men. The first type were acetylene and could only reach about 5,000 feet. By the end of 1916, the searchlights had petrol-run generators and could reach 10,000 feet. Still not very efficient when you consider that at this time, the Zeppelins were cruising at 15,000+ feet.

There were, by now, searchlights from five different companies. Many of the searchlights were on lorry chassis, mainly Tilling-Stevens chassis. The searchlights were, especially in the first 18 months of war, mainly mobile and accompanied the guns (also mounted on lorry chassis) and raced around London and the SE of England.

When the anti aircraft defences came under the army's control in February (?) 1917, there were approximately 40 searchlights which were distributed mainly to the centre and east of London - and into Kent, Essex and Norfolk (on the coastline to meet the Zeppelins and Gothas as they came in over the English Channel).

The navy men were then asked to transfer to the army - and the vast majority did so. The guns were now operated by the RGA, and the searchlights operated by men of the Royal Engineers. I hope this fits with the info you have.

I can post one or two pics, none really clear though, of a mobile searchlight. I also have a map showing the location of the fixed searchlights in and around London and the home counties.

There is a book, written in 1923, by A Rawlinson, which desribes the activities of a mobile anti aircraft unit, "The Defence of London 1915-1918." But the info is thin, and Rawlinson (ex Navy), bitter over the decision to hand over the defence to the army, spends much of the book in arguing against the decision.

I know there are files in the PRO about the Searchlight Division, but I have not had time to look at them yet.

[charlesmessenger]

To add to what Racing Teapots has said, anti-aircraft defence, including that of London, was taken over by GHQ Home Forces in 1916, although RN personnel continued to man the London defences until they were transferred to the RGA on 1 Jan 17. The RGA was responsible for AA defence in both UK and France. The searchlights were, however, manned by the REs. The same system applied to AA Command during WW2.

Charles M

[Terry_Reeves]

Just to add a little background to the post. The first RE searchlight unit was formed in 1895 by the then Tyne Divisional Engineers. Originally they were formed to work in conjunction with the Submarine Mining Companies. After the disbandment of the latter, they continued as Electric Light Companies with the Fortress Royal Engineers at defended ports around the UK.

Terry Reeves

[MartinWills]

To add a little more to this thread I have some information about the London Searchlight operators. These were the London Electrical Engineers R. E. (T). I have a few copies of their magazine "The Skyscraper" which is an interesting mix of anecdote, humour and some technical articles. In December 1918 they celebrated with a dinner at the Cafe Monici "chaired" by Lt. Col. A E Le Rossignol C.B. T.D. who was O.C at the time.

I will pass on the calculation of the candle power of a searchlight beam, or the mathematical formulae for the ratio of effective lengths of twin and single beam (serchlights). Interestingly the effective length (i.e. range) of a twin beam searchlight is a mere 1.19 times that of a single beam unit. Following on from this it is deduced that sixteen co-incident beams would be required to give an effective length of double that of a single beam.

I will close on a rather more light hearted electrical engineers joke:

Q. Why did the beam sweep?

A. Because it saw the carbon brush.

Martin

[martinclift]

On ‎10‎/‎15‎/‎2003 at 23:01, MartinWills said:

To add a little more to this thread I have some information about the London Searchlight operators. These were the London Electrical Engineers R. E. (T). I have a few copies of their magazine "The Skyscraper" which is an interesting mix of anecdote, humour and some technical articles. In December 1918 they celebrated with a dinner at the Cafe Monici "chaired" by Lt. Col. A E Le Rossignol C.B. T.D. who was O.C at the time.

I will pass on the calculation of the candle power of a searchlight beam, or the mathematical formulae for the ratio of effective lengths of twin and single beam (serchlights). Interestingly the effective length (i.e. range) of a twin beam searchlight is a mere 1.19 times that of a single beam unit. Following on from this it is deduced that sixteen co-incident beams would be required to give an effective length of double that of a single beam.

I will close on a rather more light hearted electrical engineers joke:

Q. Why did the beam sweep?

A. Because it saw the carbon brush.

Martin

 

Very Interested in this topic as I am researching the 1st & 2nd London Electrical Engineers. My work centres on the three forts across the Thames, Coalhouse, Cliffe & Shornemead. Lt. Col. A E Le Rossignol C.B. T.D, as you quite rightly said, was the O.C. Coalhouse Fort printed their magazine, which they called 'The Searchlight'. I have almost all that were printed in digital format. I would be very interested to read what you have and also hear of any information you have on the lads that printed 'The Skyscraper'.

This work is being conducted on behalf of Coalhouse Fort and Thurrock Museum and will be preserved.

 

I realise this is quite an old thread, but I am hoping that you have something.

 

Looking forward to hearing from you, Martin.

 

Martin