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ASN Wikibase Occurrence # 218265
Last updated: 5 June 2020
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Time:09:25 LT
Type:Royal Aircraft Factory BE.4
Owner/operator:3 Sqn RFC
Registration: 204
C/n / msn:
Fatalities:Fatalities: 2 / Occupants: 2
Other fatalities:0
Aircraft damage: Written off (damaged beyond repair)
Location:Netheravon, Salisbury Plain, Wiltshire -   United Kingdom
Phase: Manoeuvring (airshow, firefighting, ag.ops.)
Departure airport:RFC Larkhill, Salisbury Plain, Wiltshire
Destination airport:
11.3.1914: Royal Aircraft Factory B.E.4 204, 3 Squadron, Royal Flying Corps, RFC Larkhill, Salisbury Plain, Wiltshire. Written off (destroyed) when spun into the ground after rudder lost, Netheravon, Wiltshire. Both crew - Capt Clement Robert Wedgwood Allen (pilot, Welch Regiment, aged 35) and Lt James Edward Godfrey Burroughs (passenger, aged 30) - were killed. The B.E.4 was structurally identical to the B.E.3, with staggered two-bay wings, a low long rudder and the fuselage suspended between the upper and lower wings. It made its maiden flight on 24 June 1912, just over a month after the B.E.3 had been handed over to the R.F.C. The B.E.4 followed it on 8 August 1912.

The enquiry into the crash was inconclusive, but suggested that the metal in the rudder shaft had become crystallized, weakening it enough for it to snap. If this was the case then this was one of the first recorded incidences of metal fatigue as the cause of an aircraft crash.

According to the following report in Flight magazine (31 July 1914 page 809):


Brief Description of the Accident.—
Capt. C. R. W. Allen was flying a B. E. Biplane, No. 204, fitted with an 80 h.p. Gnome engine, with Lieut. J. E. G. Burroughs as passenger, at Netheravon, Salisbury Plain, on Wednesday, March 11th, 1914. The aircraft, which had been in the air about 5 minutes, had made nearly a complete circuit and was turning in the direction of the sheds. When at a height of about 350 feet, the rudder was seen to leave the aircraft, which then made a spiral dive to the ground. The pilot and passenger were both killed and the aircraft was completely wrecked.

Capt. C. R. W. Allen (aged 36) was granted his Aviator's Certificate, No. 159, on November 14th, 1911, by the Royal Aero Club, and Lieut. J. E. G. Burroughs (aged 30) was granted his Aviator's Certificate, No, 1213, on January 31st, 1913, by the Aero-Club de Fiance.
The Committee sat on June 16th and 30th and July 14th and 27th, 1914, and received the report of the Club's representative who visited the scene of the accident within a short time of its occurrence, together with the evidence of eye-witnesses. The Committee also had before them the report of the National Physical Laboratory, dated May 20th, 1914, on the fracture of the rudder post of B. E. Biplane No. 204. In this report the condition of the metal of the steel tube which formed the rudder-post has been very thoroughly investigated.

The Committee was also furnished with the results of mechanical tests on similar rudders manufactured at the same time. From the consideration of the evidence the Committee regards the following facts as clearly established:—

1. The aircraft was built by the Royal Aircraft Factory in June, 1912.
2. There was practically no wind at the time of the accident.
3. The main rudder tube was fractured at the base of the rudder just below where the rudder-post passes through the frame of the rudder and is welded to it.
4. The rudder which became detached from the aircraft in the air was picked up 126 yds. from the spot where the aircraft fell.
5. The control wires were found to be intact.

The Committee is of opinion that the rudder was sufficiently strong to withstand the ordinary stresses of flying but was insufficiently strong to resist the greatly increased stresses of modern flying and rough usage, and had probably been damaged in this way prior to this particular flight.

In consequence of the greatly augmented stresses now imposed on aircraft due to the increased skill and daring of aviators in high winds in connection with sharp turns and similar manoeuvres, it is recommended that the attention of constructors be drawn to the necessity of making due allowances for these increased stresses, combined with proper allowances for deterioration due to wear and tear, and the possibility of flaws in the materials themselves."

According to the following transcript from the Coroners' Inquest report:

"Allen, Clement & Burroughs, James
March 20th 1914

The Flying Disasters
Grave Evidence at the Inquest

The inquest on Captain Allen and Lieut Burroughs, who lost their lives in a flying accident on Salisbury Pain on the previous Wednesday, was held at Bulford Military Hospital by the South Wilts Coroner (Mr F H Trethowan) on Friday afternoon. Mr H Bowden was foreman of the jury and in addition to the witnesses there were several officers of the Royal Flying Corps present, wearing bands of crepe around their arms.

The first witness was Major Brooks Popham, commandant of the 3rd Squadron Royal Flying Corps to which the two officers belonged. He gave evidence of identification and said the Captain was 36 years of age, and lived at Southfield, Woodchester, Stroud, and Lieut Burroughs was 30 years of age and resided at Bristol. The witness went on to say that he did not actually order the flight on Wednesday, but he had previously ordered Captain Allen to take Lieut Burroughs for instructional flights in this machine. It was known as a B E Biplane with Gnome engine No 204. He watched the machine start off from a distance and it seemed to be flying perfectly well.

The Coroner: Is it someone’s duty to examine the machine before every flight? Yes, I have a copy of the instructions stuck up in every shed. These are the actual instructions taken out of the shed from which that machine started. They have been considered by the officer commanding the military wing and they are very full as to the duties of the mechanics in charge.

There was a mechanic in charge of this? Yes, a mechanic in charge of the rigging and a mechanic in charge of the engine. I simply produce the regulations to show that the system is a sound one.

The rudder of the ill-fated machine, and the broken bar which had connected the rudder with the biplane were produced for the jury, and Major Brooks-Popham, continuing, said the accident was caused by the rudder breaking off and falling from the machine.

“There has been so much in the newspapers which is entirely wrong about this machine,” said the Major, “that I think in justice to everybody I should make a statement. This machine is of old design but in my opinion and in the opinion of other officers who have flown it, it was a thoroughly good machine in the air. As regards its design I looked upon that machine and a similar one which I have got in the sheds as the two best wind machines I have ever flown – the best machines in a bad wind.”

Questioned as to the date of the original construction of the aeroplane, the Major said he could not give it but it was thoroughly overhauled and repaired in the Royal Aircraft Factory in September, 1913. The Log Book contained an account of everything that was done to the machine but he could not find any entry in regard to the rudder. But the whole of the rest of the machine was thoroughly overhauled so that when it was handed back to the Royal Flying Corps it was practically a new machine and to say that it was one of the oldest machines in the service was wrong.

The Foreman of the Jury: I want to know the exact date of the original construction of the machine? I can hardly tell you, but it was quite possible that there was hardly a single piece of the original machine left.

A juror: A patched-up machine?

Witness: I don’t think it is fair to call it a patched-up machine.

The Coroner suggested that members of the jury should wait until the witness had concluded his evidence and then questions could be put through him (the Coroner).

Replying to the Coroner who asked as to whether he could express any opinion as to the age of the rudder post, the witness replied that he could not.

Continuing, he said that in the log books an entry was made showing every flight that a machine did and every repair done. There were very strict instructions from the officer commanding the military wing that every repair should be entered. Capt Allen, as a flight commander, was very particular on that point. He would like to mention a little incident that brought that out. When they moved in at Netheravon the first thing that Captain Allen did was to chalk up in big letters on the wall words to the effect that every repair, however small, was to be entered at once in the Log Book. He remembered the incident, because he was rather annoyed at what he thought was spoiling the walls, but he allowed the words to remain, and he saw them there that morning. As the log book made no reference to the rudder bar, the conclusion he drew was that it was the original rudder bar made with the machine. After the accident he found that the rudder had fallen about 126 yards from the remainder of the machine. He examined the wreckage and found the controls in perfect order. The rudder bar itself was sheared off close to the joint where the frame of the rudder began. On examining the rudder post he found that the tube with which it was made was far too light a section to stand the strain to which it would it would be subjected during flight. There were three possible causes of the mishap. Firstly, the design of the machine might have been wrong, and the strains miscalculated. Secondly, the workmen who did the job might through ignorance or carelessness have put too weak a tube in ; and thirdly, the rudder post might have been changed after reconstruction – after it was handed over to his squadron. In any of these three cases there was evidence of criminal negligence on the part of the officials responsible.

The Coroner: I think that is really for the jury to decide.

Witness: If the repairs were done in my squadron, then I am responsible. If, on the contrary, the machine was handed over to me like that and nothing was done in my squadron, then I hold the officials of the Royal Aircraft Factory responsible.

The Coroner: As a matter of fact I am not sure whether it will be for us to enquire into the responsibility, because I think I shall be able to advise the jury that in such a case there is hardly criminal responsibility, and it may not be for the jury to enquire into it. In certain circumstances you suggest criminal responsibility, but I don’t think you should do that, because I don’t see any reason why you should. It is for the jury to decide whether there has been any criminal responsibility, and not for you, sir.

The Coroner pointed out to the witness that the rudder post had been lengthened by a piece of tube being let into it, and asked whether a mechanic, seeing it, would not have doubts that there was something wrong.

Witness: No, he would not.

The Foreman: You said just now that it appeared in the press that these machines were out of date?

Witness: Yes, practicably unable to fly.

The Foreman: We have to take your practical knowledge against the paper’s theoretical knowledge?

Witness: I don’t think the people who make these statements in the paper can have any knowledge of it.

The Coroner: I don’t think you ought to ask those questions. They are more or less matters of opinion. Major Brooks-Popham has said what he thinks, and you must not cross-examine him upon it unless it is to elicit some fact which is going to be of importance to this inquest. All we are doing is to inquire as to the means by which these two officers came to their deaths. We must not go too much into the question of what the papers have been saying.

A Juror: As far as we know, the rudder post is the original one made with the new machine.

The Foreman: Would it be possible for the machine to be brought to earth with the rudder broken if the pilot had the controls properly in hand.

The Witness: If the machine had been flying straight at the time the rudder came off, in my opinion the pilot would have got down safely, but from the evidence I can collect he appears to have been on the turn, and the rudder flying off then he would have had very little chance of recovering himself with the controls that remained. If he was not on the turn there was no reason for the rudder to fly off.

The Coroner: The strain in turning broke the rudder? Yes.

Frederick Michael Green, engineer at the Royal Aircraft Factory, Farnborough, was next called, and he stated that the machine was constructed in the Spring or Summer of 1912. He had examined it after the accident, and as far as he could tell, except for the rudder post being broken, the machine was in excellent order. The rudder bar had been lengthened, and provided that the work was properly done it would be safe. The post had been lengthened by 1¼ inches at the bottom end, about eight inches from the spot where the breakage occurred. The lengthening would have had no effect whatever upon the part which was broken. The original bar was approximately “20-gauge,” making it roughly one-twenty-fifth of an inch thick. That was the proper gauge according to the drawings.

The Coroner: Do you consider that thick enough? Yes.

For the strain which is placed on the bar? Yes. It is calculated in the light of existing practise.

Mr Green explained that at the point where the breakage occurred the tube was about half the thickness that it should have been, and it appeared to him that it had been filed after the lengthening work was done.

The Coroner: The thinness to which this tube had been reduced rendered it unsafe? It reduced the factor of safety. If it had been discovered it would have been changed. But taking your measurements as somewhere near the accurate, would not it be rendered unsafe as a matter of course? Not necessarily.

Would it stand considerable strain? May I explain? When the machine was last at the factory for overhauling and testing it was altered in certain ways, and a slight adjustment of the rudder was needed to make it a little higher. For that reason a piece was put in. After that the machine was flown by Mr Kemp, and we made a certain series of experiments in no way connected with the strength of the rudder, which involved making some very sharp turns. I went on the aeroplane myself with the pilot, and we made a series of sharper turns than are ever made in practise, and after that there were signs of weakness in the rudder.

Asked whether he could suggest any reason for the rudder breaking away except that it was too thin, the witness suggested that since the severe testing some nine months previously, the steel of which the post was made had suffered. The post might have been accidentally bent and straightened, and in support of this theory he mentioned that higher up on the post he found a dent in the steel which must have caused by a very sharp blow, and which, he was morally certain, was not caused by the machine falling on the day of the accident. At the Royal Aircraft Factory there was a large staff of inspectors, whose duties were precisely similar to those of the new Military Inspection Department. The rudder post on this machine was inspected by these people, and they would not have passed it if they had seen any mark on the rudder post. The presumption was that when the rudder post was lengthened it was passed, and that probably the man who was working on it filed it down. Then it was probably painted so that there was no chance of anything showing.

The Coroner: Supposing you had been in charge of the machine, and knew there was a dent, would you have straightened it out and done anything further to it, or would you consider there was a risk?

Witness: I consider there would be a risk.

Some inquiry ought to be made before straightening out a bar like this, which is bent? Yes, I put that forward merely as a possibility.

The Foreman: When the rudder broke, would it be possible for the pilot to bring the machine to earth? I think if he had been going straight he would have had a chance, but if he had been turning he would not. I think if the rudder broke while he was turning, the machine would almost certainly dive to earth.

William Press, mechanic of the Royal Flying Corps, said he was in charge of the rigging of the machine, which included everything but the engine. He examined it at nine o’clock on the morning of the accident, and found everything correct.

The Coroner: Had you ever noticed there were file marks there?

Witness: No, sir.

Looking at it now, can you see that where it was welded to the frame there have been file marks? Yes, it has been filed.

Do you know there was any risk attaching to the weld being filed like that? No, I didn’t, sir.

Using a file, you are very likely to file into the tube as well as the metal left by the weld? Yes.

You didn’t file that? No.

And you don’t know who did? No, sir.

Have you ever known the rudder post bent? No.

Never heard of it being bent or straightened? No, sir.

You don’t remember any accident to it which would affect the rudder? No, sir, I don’t. The witness went on to say that on the day of the accident he watched the machine ascend to a height of about 250 feet, and then saw something fall from the machine. It was turning fairly sharply at the time. He afterwards discovered that what had fallen was the rudder. The machine dived nose downwards, Captain Allen was thrown from the machine, and Lieutenant Burroughs was found in the wreckage. Both were picked up dead. Captain Allen was strapped to the machine, but the strap broke.

Walter John Dobson, labourer, of Netheravon, also described the accident.

Lieutenant Hopper, of the RAMC, described the injuries to the two officers. The former had severe injuries to the head and chest, and the latter injuries to the head and legs. Death was due to shock.

The Coroner, in summing up, said he thought there could not be a shadow of doubt that the breaking of the rudder post caused the accident. Why the rudder post broke was another matter, but he was afraid they were not competent to decide it, and he was not sure it was necessary for them to consider the matter more carefully than they had done. If there was criminal negligence on the part of some person, they might have something further to say about it. If a person carelessly filed away the post where it was welded to the frame of the rudder, it was probably someone at the factory, and apparently by some one at the factory after the post and the rudder had been actually passed as a unit. If so, it was a very serious thing, and whether they would ever find the man who did it was, to his mind, extremely doubtful. They did not know whether it was the filing that actually caused the breakage. Probably they would think it had something to do with it ; possibly they might think the bar was hardly strong enough to take the strain which must be put upon it in moving a big rudder.

The Foreman said that what struck him as funny was that a new bar was not put in instead of lengthening the old one; that bar had to be lengthened by two inches. It seemed to him it would have been better to put in a new bar.

The Coroner said that was a matter the foreman could discuss with the jury. The only expert evidence that they had went to prove that the actual lengthening could not in any way lessen the strength of the bar. They had heard from Major Brooks Popham how the mechanics had to go over the machines very carefully. The mechanic, even if he had noticed that the weld had been filed, would not have known that that would weaken the bar. He did not think they would be able to find there was any blame attaching to any particular person. If they did not find direct negligence on the part of anybody who they could mention by name, he would ask them to bring in a verdict of accidental death. He understood a very careful inquiry by experts would be made.

The jury, after less than a minute’s deliberation, returned a verdict of accidental death."

To avoid similar failures, the remaining aircraft were fitted with modified tails based on that fitted to the H.R.E.2, this allowing the Central Flying School aircraft to remain in use until the summer of 1914


4. Flight magazine July 31 1914 page 809 at
8. Bruce J.M. The Aeroplanes of the Royal Flying Corps (Military Wing). London: Putnam, 1982. ISBN 0-370-30084-X page 374
9. Hare, Paul. The Royal Aircraft Factory. London: Putnam, 1990. ISBN 0-85177-843-7 pages 168-169
10. Rickard, J (3 April 2009), Royal Aircraft Factory B.E.4 ,

IWM-Q67031-Royal-Aircraft-BE4 Royal Aircraft Factory B.E.4 at the Central Flying School, Upavon, 1913.(The aircraft is Serial Number 417, no photo of No.204 has been found, but the two aircraft are identical)

Revision history:

21-Nov-2018 21:21 Dr.John Smith Added
21-Nov-2018 21:24 Dr.John Smith Updated [Narrative]
23-Nov-2018 16:33 Nepa Updated [Operator, Operator]

Corrections or additions? ... Edit this accident description