Date:	Friday 2 October 1925
Time:	10:50
Type:	Brennan Experimental Helicopter
Owner/operator:	RAE Farnborough
Registration:	Unregistered
MSN:	1
Fatalities:	Fatalities: 0 / Occupants: 2
Aircraft damage:	Destroyed
Location:	Farnborough Airfield, Farnborough, Hampshire -   United Kingdom
Phase:	Take off
Nature:	Test
Departure airport:	Farnborough Airfield, Farnborough, Hampshire (EGLF)
Destination airport:
Confidence Rating:	Information is only available from news, social media or unofficial sources

Narrative:
Louis Brennan CB (28 January 1852 – 17 January 1932) was an Irish-Australian mechanical engineer and inventor. In 1916 he submitted a patent application entitled "Improvements Relating to Aerial Navigation" in which he outlined designs for a helicopter, and in June 1916 he received support for his experimental helicopter project from the British Ministry of Munitions. From 1919 to 1926 he was engaged by the Air Ministry in aircraft research work at the Royal Aircraft Establishment, Farnborough, and gave much time to developing his helicopter. The first tethered flights (inside a hangar) took place in December 1921, at which time the engine was up-rated from the Bentley BR1 to the Bentley BR2.

Flight trials in the open started in May 1924, however, on 2 October 1925, the helicopter was being demonstrated before a number of officials at Farnborough when partial control was lost. According to the official Board of Inquiry into the accident: "The tests commenced at 9.26 a.m and the accident occurred on the 4th flight which took place at 10.50 a.m. On this flight the helicopter rose to a height of between 3 ft and 4 ft. On reaching this height the pilot throttled down and commenced to descend almost immediately. On the descent a tilt of the axis developed and increased rapidly as the ground was approached. Two feet of the undercarriage touched ground together and almost simultaneously one airscrew came into contact with the ground. The second airscrew, following up, hit the ground approximately at the same position as the first, but with greater force. The first airscrew then struck the ground for a second time at approximately the same position. A subsidiary vane next touched ground and after this the helicopter slowed down and partly righted itself so that no wing structure was in contact with the ground when it came to rest. From the evidence it appears that the engine raced about the time that the second airscrew struck the ground. After this the engine was almost immediately switched off.

On the flight in question Mr. Graham found that prior to leaving the ground, the helicopter showed a slight tendency to tilt but this was easily corrected by the controls. When the machine was steady he opened the throttle and rose vertically to a height of three or four feet. The helicopter was steady and the axis approximately vertical at this height. The engine was then throttled down to about half-throttle and after the usual lag the helicopter commenced to descend. During the descent the axis started to tilt, and, in spite of the application of full control, the tilt increased until an airscrew tip struck the ground. The pilot did not switch off until the engine raced, which, in his opinion, was after the second, or probably the third impact, with the ground.

During the descent he felt no unusual motion of the helicopter, and there was no feeling of an unbalanced load on the cockpit. The motion of the machine throughout ascent and descent, other than the tilt, was smooth and normal.

The only unusual feature of the flight was the absence of side-slip on the descent. When carrying out previous flights the descent of the helicopter was always accompanied by considerable side-slip if the height reached was three feet or over. On some occasions the side-slip exceeded thirty feet. On the test in question the side-slip was negligible and the helicopter descended almost to its starting point. Mr. Graham suggested that this might be explained by the tilt occurring so rapidly that side-slip had not time to develop before the helicopter toughed ground.

The rotational speed was about 52 r.p.m. on touching ground. There was no swing of the pilot's cabin relative to the ground on the descent".

The government had spent a large sum of money on it (£55,000), and the Air Ministry was still offering an award of £50,000 for the developments of a successful machine, but in 1926 the air ministry gave up funding the Brennan helicopter project, much to Brennan's disappointment.

According to a contemporary newspaper report ("Western Gazette" - Friday 09 October 1925)

"STRAIGHT UP" FLYER CRASHES ON INITIAL FLIGHT AT FARNBOROUGH.
An experimental flight of the British helicopter, a machine designed for rising virtually, at Farnborough, Hampshire, on Friday, ended in disaster. The helicopter was taken out of its shed with Mr. H. Graham in the pilot's seat, and with Mr. Brennan, the inventor, who also invented a torpedo and the monorail, and a number of officials of the Air Ministry watching the proceedings. Hardly had the machine taken to the air, however, when it came to ground a whirling mass, and buried its nose in the earth. Both propellers were broken, a wing was damaged, and the body was severely strained. The pilot escaped injury, but it was only at great personal risk and with considerable difficulty that he retained sufficient control to save the machine from total destruction."

This accident was probably the death knell for the project, as it had been abandoned by February 1926, according to another contemporary newspaper report ("Evening Post" - Friday 19 February 1926)

"...The memorandum stated that it had been decided to close down the attempt to construct a helicopter in a Government establishment to the design of, and under the supervision of, Mr. Brennan. The Air Minster was advised by the Aeronautical Research Committee that, in spite of the great mechanical ingenuity of the apparatus, the progress made with the experiments did not warrant their continuance, and had felt compelled with regret to accept this advice".

The whole project was debated in the House of Commons on 31 March 1926, as Members of Parliament were concerned about the amount of taxpayers money that the project had consumed: £55,000 (equivalent to approximately £3.39 million at 2019 prices), albeit over nine years. According to "Hansard" the official record of debates in the Houses of Parliament:

"Mr. G. HARVEY asked the Secretary of State for Air: (1) if he is in a position to state what is the total cost of the Brennan helicopter, apart from the £50,000 paid to the inventor, in the shape of material and labour borne by the Royal Aircraft establishment at Farnborough;(2) what has become of the Brennan helicopter; and has the inventor been allowed to take it away or does it remain the property of the Government?

Sir S. HOARE
As regards the first question, the sum of £55,000, which I have stated to be the total amount expended on the Brennan helicopter experiments at the Royal Aircraft Establishment, Farnborough, was not all paid to the inventor, but includes £40,000 ​ representing the cost of labour, materials and establishment charges at the Royal Aircraft Establishment, and £7,000 for salaries of the design staff working under Mr. Brennan.

As regards the second question, in view of the decision not to incur further expenditure upon the Brennan helicopter, the damaged machine has been offered to the inventor."

Even though most components were undamaged, Brennan’s helicopter was never repaired. He would attempt to resurrect his helicopter and monorail projects in the following years, investing all his own money in them. He was unfortunately just too far ahead of his time and it would bankrupt him.

Louis Brennan would die in September 1932 from injuries sustained in a car accident in Switzerland the previous January. He was buried in an unmarked grave in London and lay in this anonymous resting-place for over eighty years, an ill-fitting place for a man who made such a mark on the world.

Thankfully, in 2014, this wrong was righted when fellow Castlebar native, Taoiseach Enda Kenny, unveiled a new gravestone on the site and a plaque was erected in his home town. This memorial finally honoured one of Ireland’s greatest engineers and, with over forty unique inventions, its most prolific inventor. The Brennan Helicopter made over 70 free flights, and it was the first helicopter to fly in the United Kingdom.

1. https://en.wikipedia.org/wiki/Louis_Brennan
2. https://hansard.parliament.uk/commons/1926-03-31/debates/55e1f4f7-103a-4915-a7ba-6e308d68c84a/BrennanHelicopter
3. http://sussexhistoryforum.co.uk/index.php?topic=8533.0
4. "Improvements Relating to Aerial Navigation", GB Patent 281735, 19 May 1916
5. Sandow, Mary (1969). "Brennan, Louis (1852–1932)". Brennan, Louis (1852 - 1932). Australian Dictionary of Biography, Volume 3. Melbourne University Press. pp. 223–224.
6. Progress of British Aviation, Hull Daily Mail, 14 Oct 1925, p.7
7. Serle, Percival (1949). "Brennan, Louis". Dictionary of Australian Biography. Sydney: Angus and Robertson.
8. https://oldmachinepress.com/2015/01/08/brennan-helicopter/
9. RAE Farnborough accident report: https://www.secretprojects.co.uk/threads/brennan-helicopter.25142/#post-255864
10. https://www.irishtimes.com/life-and-style/people/louis-brennan-the-inventive-life-of-the-monorail-man-from-mayo-1.1757782

Date/time	Contributor	Updates
21-Feb-2020 12:24	Dr. John Smith	Added