Aeroplane klaxon?

[alex falbo]

I came across a passage while studying Arras which described the 2nd Cdn Division's assault on Vimy. During the attack "Co-operating aeroplanes swooped low, sounding their klaxon horns and endeavoring to mark the progress of the troops in the driving snowstorm."

I had never encountered this signal method before. Can anyone give other examples of its use? I'm aware of Morse signals but I've never encountered the above. It was quoted from the Nicholson book on the CEF 1914-1919.

Alex

[Dolphin]

Alex

The use of klaxons was common in 1917, but the results were mixed. The Contact Patrol aeroplanes would fly over the battlefield, sounding their klaxons as a signal to the infantry to fire flares to indicate their positions. However, the infantry very soon realised that a flare can be seen by the enemy as well, and it could be an invitation for artillery attention, so the klaxons tended to be ignored.

I hope this helps you.

Gareth

[centurion]

So they kept using the klaxons as an indication for infantry to lay out signal panels

[alex falbo]

This is helpful thank you gentlemen. Gareth, were these aircraft usually single or two seaters?

Was this technique first used at Arras or all along the British frontage in early 1917? Would it be correct to assume this practice continued until the end of the War with infantry responding with the signal panels?

[centurion]

This is helpful thank you gentlemen. Gareth, were these aircraft usually single or two seaters?

Was this technique first used at Arras or all along the British frontage in early 1917? Would it be correct to assume this practice continued until the end of the War with infantry responding with the signal panels?

The first contact patrols (so described) were flown by No 4 squadron in May 1915. Klaxons were certainly used by No 15 squadron at Vimy Ridge over the Canadian lines. Klaxons were certainly fitted to RE8s and FK 8s Signal panels in one form or another were in use until the wars end (and remained part of army/air cooperation up into WW2)

[centurion]

However I think at some stage the German practice of using coloured streamers to indicate which infantry unit was being sought may have replaced the Klaxon but possibly not until post war. There is a medal citation from late 1918 for a British pilot whose klaxon had been hit by enemy fire going really low to make contact.

[egbert]

I have read in several German primary sources that the German infantry hated the klaxons because they were used for directing British artillery on German positions, bunkers and trench sections with movements. When the artillery observer airplanes arrived life freezed in the German trenches to avoid detection and subsequent artillery fire. Again British artillery observers in the planes precisely directed their own artillery with klaxon signals

[Jack Sheldon]

I included an example of this practice in my German Army on the Somme book p 209. A member of RIR 76, operating near Delville Wood on 25 Jul 16 noted, 'Enemy aircraft were operating all over the battlefield. Flying fairly low, they gave horn signals from time to time. They were clearly indicating the whereabouts of thickly occupied shell holes to their artillery, which increased its rate of firing ...'

Jack

[centurion]

I have read in several German primary sources that the German infantry hated the klaxons because they were used for directing British artillery on German positions, bunkers and trench sections with movements. When the artillery observer airplanes arrived life freezed in the German trenches to avoid detection and subsequent artillery fire. Again British artillery observers in the planes precisely directed their own artillery with klaxon signals

Can't understand how klaxons could be used to direct artillery miles in the rear and unable to hear them. Artillery observers were not carried on contact patrols. Possibly someone in the German infantry incorrectly understood the purpose of the klaxon and the misunderstanding developed into trenchlore

[Jack Sheldon]

I take your point Centurion. However, I am with Egbert on this one. The man I mentioned in my last post went on to say that whenever an aircraft flew near to their shell hole, they all feigned death, so as to avoid the risk of being shelled. His context was, of course, shell hole defence during a British attack. This German tactic forced the Allies to expend huge quantities of speculative fire, because their guns no longer had precise trench lines to aim at. I can well believe that any measure which would aid aiming would be tried and I am sure that artillery observers were employed forward, or at least in overwatch positions during these attacks which, let us face it, were conducted over short distances only and, frequently, for long periods over precisely the same ground. The actual location of the gun lines is irrelevant. All it took was an intact telephone line.

Jack

[centurion]

I take your point Centurion. However, I am with Egbert on this one. The man I mentioned in my last post went on to say that whenever an aircraft flew near to their shell hole, they all feigned death, so as to avoid the risk of being shelled. His context was, of course, shell hole defence during a British attack. This German tactic forced the Allies to expend huge quantities of speculative fire, because their guns no longer had precise trench lines to aim at. I can well believe that any measure which would aid aiming would be tried and I am sure that artillery observers were employed forward, or at least in overwatch positions during these attacks which, let us face it, were conducted over short distances only and, frequently, for long periods over precisely the same ground. The actual location of the gun lines is irrelevant. All it took was an intact telephone line.

Jack

During the first year of the war British troops became convinced that the presence of one of their own aircraft overhead attracted German shelling (and often fired on them). In fact it was the shelling that tended to attract aircraft rather than the other way round! But it took the high command considerable time and effort to convince the troops that British aircraft were an aid not an attactor of shell fire [one can see why as the illogic must have been 'whenever we are shelled there is usually one of our aircraft around therefore our aircraft attract shell fire]. Similarly just because the Germans believed the British aircraft were linked to the artillery doesn't make it so [possibly the same sort of circular logic 'when there are British aircraft around we get shelled therefore the aircraft bring the shelling" when in fact the contact patrols will be there because in part of the shelling to ensure that the position of British troops is known so they don't get shelled]. To use contact patrols for artillery direction would mean a system of signals so that the forward artillery observer could distinguish "worthwhile target" from the instructions that the aircraft is giving to the infantry (its prime job) a complication that could lead to fatal misunderstandings amongst the infantry [and for that matter friendly fire instances]. There is no evidence that such a system existed however even if it did how on earth did the observer signal the position of the shell hole so the guns knew where to fire? All a forward artillery observer could see would be an aircraft five hundred feet above the battle field with its klaxon going. Which shell hole is it referring to? what are its coordinates? If he has an intact phone line he can't be that far forward so the aircraft is ahead and in front of him and moving. It can't hover over the relevant shell hole with its klaxon going. Sorry but the idea is nonsense.

[mickdavis]

I came across a passage while studying Arras which described the 2nd Cdn Division's assault on Vimy. During the attack "Co-operating aeroplanes swooped low, sounding their klaxon horns and endeavoring to mark the progress of the troops in the driving snowstorm."

I had never encountered this signal method before. Can anyone give other examples of its use? I'm aware of Morse signals but I've never encountered the above. It was quoted from the Nicholson book on the CEF 1914-1919.

Alex

Can I recommend the excellent Michael Meech article on Contact Patrols that appeared in Cross & Cockade Vol40/2, which examines, detail, the methods of air-to-ground and ground-to-air signalling. Subsequent articles by Michael have also examined contact work with tanks and German contact patrol techniques. There's more in the pipeline; American and Italian contact patrol procedures.

[Jack Sheldon]

I certainly would not die in the ditch over this; I do not know enough about the subject. However, inspired by the discussion I have taken another look at The War in the Air Vol II, pages 233 and 247. On p 233 it is pretty clear that the primary use of the klaxon was to get the forward infantry to light their flares and so show the contact patrol their frontline trace. I suppose you could argue that, armed with that knowledge, gun fire could be brought down forward of that line (and probably was), but that its main, or perhaps sole, aim was to communicate with friendly forces. The other reference (p 247) is interesting. An aircraft of No 3 Sqn flew over Ginchy prior to an attack on the place on 3 Sep 16 and, ' ... at one point where the pilot flew low over huddled Germans he concluded from their complete inactivity that they were corpses.'

Further evidence that the klaxon was mainly for friendly communication comes from Somme Success Peter Hart Pen and Sword 2001, where, in Ch 3, he quotes Cecil Lewis, of Sagittarius Rising fame, who explains the difficulty of getting the infantry to respond in an actual battle situation, even when the klaxon had been used correctly, 'because it drew the fire of the enemy on to them at once.' There is also an item of interest in Royal Flying Corps 1915-1916 Christopher Cole (Ed) London 1969 p 245, where part of one of the official communiques is a description of an aircraft flying at night and getting lost on 4 Sep 16 after a bombing mission. '[He (the pilot)] sounded its Klaxon horn. Numerous very lights and rockets were sent up, which enabled him to pick up his bearings.'

Jack

[centurion]

An account by Lieutenant Richard Sheraton of 59 Squadron shows how the klaxon was used and coincidently just how easy it would be for the Germans to associate this with artillery fire. I enclose a brief extract

"as we approached the line we were flying through our own artillery barrage, which was the thickest I had ever seen. The Huns were firing machine guns at us from the flanks, I recollect, as we went down, calling "A.A." continuously on the klaxon. I was able to mark the positions of the advanced Infantry Units, who had marked them by lighting red flares, just as the day was dawning. These positions were entered on maps in triplicate, and copies were dropped by me at the Headquarters of the 34`"Division and the 3rd Corps."

As well as flying contact patrols he also did artillery shoots but not both at the same time.

From Library Reference Number: 103 Scottish Saltire Branch, ACA

[egbert]

I have read in several German primary sources that the German infantry hated the klaxons because they were used for directing British artillery on German positions, bunkers and trench sections with movements. When the artillery observer airplanes arrived life freezed in the German trenches to avoid detection and subsequent artillery fire. Again British artillery observers in the planes precisely directed their own artillery with klaxon signals

The airborne artillery observers I read about used sort of morse code when sounding their klaxons, long-long-short-long-kind of thing. Maybe in connection with map coordinates they informed own arty (directly or via ground arty observer???) where to fire at.

[centurion]

The airborne artillery observers I read about used sort of morse code when sounding their klaxons, long-long-short-long-kind of thing. Maybe in connection with map coordinates they informed own arty (directly or via ground arty observer???) where to fire at.

clutching at straws

[egbert]

clutching at straws

Why do you quote me when you monologize?

[truthergw]

I suppose that an air observer could communicate with artillery by a simple, 'yes you hit it ', ' no he is still there'. That, as Egbert says, would be easy enough to sound on a klaxon. In other words, the targets were known and the plane is simply indicating whether it had been hit or not.

[domsim]

The following from a description of the Imperial Camel Corps attack on the hejaz railway station at Mudawarra in August 1918, quote by Laurence Moore, signals man in Geoffrey Inchbald's book 'With the Imperial Camel Corps in the Great War.'

“When the light was good a couple of planes of the Hejaz flight (X flight, 14 SQN.) came over and I had the job of controlling what must have been one of the first ever ground to-air controlled bombardments. We had no radio so the planes spoke to me in Morse by Klaxon horn, and I was able to tell them where I was by a smoke bomb and put out letter signals by prearranged code. After the planes had each dropped from almost ground level, a couple of sixty pound bombs on the stony northern redoubt, the Turks came streaming out, waving any dirty rag that could serve as a white flag, and I gave the planes the signal ‘Cease Fire.’

I don't know about the claim at the beginning but Moore states that the X flight planes were transmitting Morse code signals.

All the best

Dominic

[MikeMeech]

Hi All

As Mick Davies mentioned I have done a bit of work on Contact Patrols and the use of the Klaxon and I will briefly discuss its use. (I aim to do an article on the Klaxon at some stage).

First there was some early use of the Klaxon from aeroplanes in 1912 and 1913, reports on this can be found in the 'Flight' online archive, both in civilian and military contexts to send Morse messages to the ground. Grahame-White at Hendon was involved in this and there are photographs showing his aircraft fitted with them. One was actually found for me by the Andy Renwick of the RAF Museum on Monday, this showed one fitted to a Henry Farman and matches a report and drawing that can be found in the Oct.12 1912 edition of 'Flight'.

It appears it was hoped that the Klaxon would be useful for sending actual messages in Morse on the battlefield to artillery and HQs, however, with the 'background' noise this messages could become indistinct.

Contact Patrol Use - This was the main use for the Klaxon, and there are now quite a few photos of aircraft such as RE.8s FK. 8s and FE.2b with them fitted, mainly found through the help of CCI members and RAF Museum staff after I started to 'bore' them with the subject. None have yet turned up on BE.2, or other early aircraft of the RFC, but they must be out there somewhere. The use the Klaxon was put for Contact Patrols was to call for Flares, panels etc of front line troops and for Battalion/Brigade HQs to show their ID. A series of 'A's or a long hoot would be sounded for this , usually in conjunction with a 'Very' light or later a special smoke bomb, it would also sound 'T' or 'RD' in acknowledgement to ground messages. It appears from TNA AIR 1 documents that it came into major use for this purpose during the Somme in July 1916 and was adopted as 'standard' by August. From then until the end of the war it is in the Appendix 'B' of SS.135 as standard for troops to know. There were problems with it relating to pitch, which could be different in individual equipments and there is correspondance on this in the AIR 1 docs. I also have a copy of Orfordness & Butley report on 'Sound Signalling from Aircraft (RAFM) which have examples of proposed replacements for the original Klaxon. However, it appears that the sound systems used by other nations for the same purpose, such as the Germans and Italians , was the use of machine-gun fire to 'attract attention', the French and Americans appear to have used a mixture of the two at the time, but I am still working on this. But overal I think the KLaxon was probably the better of the two sound signals.

There were other uses, from 1916 it was used by night flying aircraft to indicate there were friendly to AA guns and ground forces when flying over 'Defended Areas', this was reissued with modifications in 1917 and there is correspondence on warning airman to use it or the ground troops have every right to shoot at you!

A third use that came up during my research was it being used as an 'inflight' communication system on the DH.4 (and Sopwith 11/2 Strutter). Again this was an Orfordness experiment (the report was reprinted in an USAS Air Bulletin No.180) in early 1917. I believe there is a photo of this fitment in the Airco DH.4 Windsock Datafile Special Vol.1 by Jack Bruce. (page 50 photo 119) this is captioned as for contact patrol use but I think by the date and fitment it relates to that experiment.

So briefly that is Klaxon use in WW1 by aircraft. I do have a lot of detail on this and I am still finding things, but if anyone whats greater info please do ask. Not to mention reading my articles in the relevant CCI Journals if you wish.

Mike

[Jack Sheldon]

Mike

From that quote from Cecil Lewis I mentioned previously, it is clear that he was flying a Morane Parasol, so that would be somewhere else to look. He actually stated, 'We had a klaxon horn on the undercarriage of the Morane - a great big 12 volt klaxon and I had a button which I used to press out a letter to tell the infantry that we wanted to know where they were.'

Jack

[centurion]

Have done some digging which I will post results of in detail later but in general

Klaxons were used as early as the Somme by contact patrols

In no contemporary British, Australian, Canadian or American accounts is there any reference to contact patrols communicating with artillery by Klaxon, indeed the only reference to any communications with artillery by contact patrols(in one US manual) specifically forbids this stating that only wireless is to be used.

Morse was used for Klaxon signals but only for single letters eg 'A' meant show me where you are. There was one that said Counter attack imminent. Details of a training course for contact pilots indicate that is was difficult for morse signals to be clearly understood on the ground so Klaxon signals had to be very simple and slow

More detailed communication from the aircraft was by message bag and there was a morse letter to indicate "am dropping message"

Signals from the ground other than coloured flares was by message panel, mirror, or klaxon - again single letters with meanings such as "held up by wire", "more artillery fire needed", "low on ammunition". These would be noted by the aircraft observer and relayed back along with maps showing the troops positions by message bag drop

[MikeMeech]

Hi Jack

Yes there should be photographs of Morane Parasols in existance and one day we may find them. I have had a great deal of help with this Contact Patrol project from various people including Stuart Leslie (who knows a bit about WW1 photos). One of the initial problems was knowing what a Klaxon looked like anmd where they would be located. On RE.8s and FK.8s they are under the fuselage (not necessarily in the same location) but we then found some had been staring us in the face for years. One was of W G Barker (later VC) posing in front of his 15 Sqn. RE.8 with the Klaxon visible between the undercarriage struts attached under the fuselage, and also of Freddie West (later VC) where he and an Italian officer are posing in front of an FK.8 of 8 Sqn. (then a tank support sqn) again the Klaxon can be seen under the fuselage between them (both photos can be seen in Chaz Bowyer's 'For Valour' and many other books or articles). Another photo from the JMB/GSL collection of RE.8 'A3213' of 59 Sqn. dated 25.9.17 shows just the 'horn' end sticking out of the bottom of the fuselage at the rear of the front cockpit area. In all these cases if the angle of the photo is 'wrong', people in the way or there is too much shadow the Klaxon will not show up. Each Corps Sqn would be equipped with six Klaxons according to contemporary paperwork from TNA, these could be removed or put on when needed, they were operated by a Morse key.

I used a quote from 'Sagittarius Rising' (page 85-86) in my summer 2009 article in CCI Journal. The official report in AIR 1/823/204/5/43 'Notes on Contact Patrol Work, August 1916' was a bit more positive and much more development was achieved that year with the 'Provisional Instructions for Contact Patrol Work by Aeroplanes' being issued in December 1916. Before the Somme started the procedures were based on previous small scale British battle experience and trials and, importantly, on French experience during Verdun and the 'Joffre Memorandum' which stated the French procedures.

There was a continual problem of 'lack of flres' from the Infantry throughout the war, not only because a desire not to show their position to the enemy, but also due to running out of flares or the flares getting damp and not being of use. This is why alternative equipment was used at different times, eg. Tin Triangles on the pack during the early stage of the Somme, Cloth Flaps on packs, Tin discs to shine in the sun to indicate the location, Watson Fans, 3 to 4 rifles laid in parallel on the ground and the extra flap on the Gas Mask Haversack which when opened showed white cloth and a tin disc which could be flapped by the soldier.

The Official History Vol. 4 page 126, on the situation during 1917 states that contact patrol aircraft, in general, had:

"...no difficulty in plotting the position of those troopswho had previously practised similar co-operation with aircraft or had been well instructed with lectures on its difficulties and importance."

Where the flares were not shown then the aircraft would have to fly at 500 ft or lower to identify uniforms, this added risk to the airmen, although, maybe surprisingly, they were still more likely to be badly shot up rather than shot down. All documents state the risk to contact patrols from enemy aircraft was minimal. Another interesting document that relates to this is SS.205 'Notes on Observation From Aeroplanes' dated February 1918 and issued down to Battalions, Batteries and Regiments. (later AP 159 and available at the RAF Museum archives).

I hope that is of help, I always welcome more pairs of eyes when it comes to looking for photos both of Klaxons on different types of aircraft and the ground equipments used by the Infantry, some of which I have asked about before on this Forum.

Mike

[MikeMeech]

Hi everyone

For your interest here is a copy of 'Revised Signals between Aeroplanes and Infantry' for 6th Division dated 4th January 1917.

Mike

[MikeMeech]

Hi again

Here is an extract from SS.205, page 6, mentioning the lack of interference from German aircraft. By the way the previous document was from AIR 1/2251/209/54/13.

Mike