Lee-Richards Annular Monoplane

Lee-Richards Annular Monoplane
	; Second machine with the additional elevator, early 1914
Type:	Test aircraft
Design country:	United Kingdom
Manufacturer:	Cedric Lee and George T. Richards
First flight:	November 23, 1913
Number of pieces:	3

The Lee-Richards Annular Monoplane (German about: Ringflügel-monoplane) was an experimental aircraft designed by the British Cedric Lee and George T. Richards from the time before the First World War . The plane had the rare design as a disk plane, but had a ring section in the middle, in which the crew and the aircraft engine were housed. The appropriate designation for this is not clear in German usage, so such aircraft are called ring-winged , circular-winged or disk aircraft . In 1954, the trade journal Flight presented the Lee-Richards construction in retrospect as the "Original Flying Saucer ", which was presented before Winston Churchill and Lord French .

history

Kitchen ring-winged

The Lee-Richards Ringflügler goes back to the developments of Isaac Henry Storey and John George Kitchen, who from 1909 dealt with this type of aircraft, which is also described as an orbicular aircraft. The inspiration for this development came from the experiments carried out by Kitchen with parachutes, which were given a central opening in the canopy for stabilization. The Kitchen airplane was a biplane built in 1910 with two superimposed ring wings and a gondola suspended between them, which accommodated the pilot and a 50 hp radial engine from Gnome . A replica of the aircraft used in the movie The Daredevil Men in Their Flying Chests is now in the Newark Air Museum .

In late 1910, Cedric Lee, a wealthy weaving mill owner and engineer, bought the ring-wing aircraft built by John George Kitchen with the intention of developing it further. At the same time, Lee met George Tilghman Richards, a former draftsman who had started his own business as a freelance engineer and designer in Manchester, and offered to help with the planned work on the Kitchen aircraft. However, this had not yet risen from the ground. Even after a few modifications, further flight attempts failed. The aircraft was damaged during take-off attempts and was also irreparably damaged in the night of November 4th to 5th, 1911 by a storm that destroyed the hangar.

New development of a glider

After these setbacks and failures, the decision was made to temporarily stop the motor-driven experiments and to work again with models and full-scale gliders . There were quite different opinions between Lee and Kitchen about the respective structural design of the test aircraft, also with regard to the aerodynamic function of the ring wing. According to Kitchen's ideas, a 1.40 m wide paper mache model was successfully tested in flight in the parade hall in Lancaster. The silk-covered “half-double-decker” model that was subsequently tested also showed good results, so that a man-carrying glider was designed and built in January 1912 with the same design. The flight tests took place in a remote area of the Westmorland Hills between Whittington and Kirby Lonsdale.

The aircraft had a wingspan of 6.70 m, a wing area of 37.2 m ² and a curb weight of 98 kg. With a flight mass of 175 kg, 35 km / h were reached in gliding flight. The construction of the wing structure consisted of two braced ring-shaped tubular frames that were firmly attached to the fuselage. The pilot sat in the circular section of the lower wing and steered two elevators in their trailing edge. Longitudinal stability should be achieved by a sharply tapering rear edge of the lower ring. The upper wing was only designed as a "half-surface" without a central hole. After a few attempts, a construction similar to that used by the Wright brothers on their flights in 1905 served as the starting device. A drop weight was used and the glider, which was lying in a wooden trough, was accelerated on the 15 m long starting rail to speeds of up to 48 km / h. The flight tests, which proceeded without incident, lasted 10 months and were carried out repeatedly in winds of up to 64 km / h.

At the end of 1912 Lee and Richards gave up their collaboration with Kitchen and went to London to carry out systematic wind tunnel tests. A wind tunnel designed and built by both of them with a diameter of 0.61 m was then built at East London College . This was probably based on ideas from AP Thurston, an aviation teacher at the college. Sir Archibald Sinclair (Fourth Baronet of Ulbster, Caithness ), whose interests also included aviation, made a significant financial contribution . "Model number 11" was selected from the extensive tests with biplane and monoplane and also tested at the National Physical Laboratory in May 1913 for comparison purposes. For lift and drag there was good agreement with the results at the Lee-Richards wind tunnel, only significant differences were found when determining the position of the center of lift .

First motor-powered Lee ring-wing aircraft

Based on this newly acquired data, Richards revised his concept of a motor-driven ring-wing aircraft. Then Blackburn Airplane Company was given the contract to build an aircraft, but then terminated and finally transferred to James Radley and Eric Gordon England . The latter had qualified for this task by having recently designed and built a floatplane, the Waterplane . Gordon England took over the transfer of the aerodynamic ideas of Lee and Richards into an engineering design based on the rules of technology. For the difficult construction, for example, a special circular table had to be developed as a falsework for the radial arrangement of the wing ribs. In addition, England should then act on a fee basis as a test pilot of the new aircraft.

Lee had the construction carried out in strict secrecy in a hangar that was guarded day and night. As with the gliders, the wing, based on wind tunnel model no. 11, was built on two concentric rings made of steel tubes, which were connected at certain intervals by tube spacers. The ribs were arranged radially around the center of the ring and the entire unit was braced by wires to form pylons that protruded above and below the wings. The result was a V-position of 5 °. The trailing edge was formed by articulated surfaces which, when operated together, acted as elevators and when operated against each other, acted as ailerons. The trunk structure, which was built on four longerons and braced, had a square cross-section. The pilot sat in the back seat, the drive consisted of a seven-cylinder Gnome rotary engine that was supposed to produce 80 hp, but actually only delivered 67 hp. Via a 1.20 m long hollow shaft, the engine acted on a two-bladed propeller located in front of the ring wing. The span was 6.71 m, the length 7.17 m and the wing area 26 m ² . When fully loaded, the machine had a mass of 773 kg, but on the actual flight it weighed only 681 kg.

The first flight took place on November 23, 1913 at the Shoreham Aerodrome with Gordon England at the wheel, with a top speed of almost 140 km / h. During the approach, the engine stalled, the machine touched telegraph lines and was destroyed on the following ground impact. England was thrown out of the cockpit but survived with minor injuries. In the reporting that followed, the name donut for the ringwing was mentioned for the first time.

Second machine

Immediately after the accident, Tilghman Richards began work on building a new, modified machine, using the engine, drive shaft and propeller from the first example. In January of this year, the Committee of the Royal Aero Club announced that it would select three representatives for the British Empire for the 1914 Gordon-Bennett Aviation Cup . In addition to numerous other applicants, Cedric Lee also submitted his proposal for two aircraft, probably ring-winged aircraft, at the end of February 1914.

The second ring-winged wing, completed in early 1914, largely corresponded to its predecessor in terms of size and appearance. The most noticeable difference was an additional pair of elevators, which were attached to the tip of the rudder fin. The V-position of the wing was reduced to 3 °. After a few short flight jumps, England probably carried out the first real flight with the improved machine between mid-February and early March 1914, which took off at 48 km / h and rose to 300 m at 150 m / min. The maximum speed on this flight was around 130 to 138 km / h.

After more than 25 hours flying this machine, England came to the conclusion that the design still needed some revision. Above all, he complained about the strong tendency to yaw when the aileron was operated, which often led to a spin . When no remedy could be found by the end of March / beginning of April, England terminated its employment as a test pilot. Gordon Bell was hired to succeed him . During a flight on April 26, 1914, the second machine crashed not far from the crash site of the first version. This time too, the pilot survived the accident without serious injuries. A subsequent accident investigation revealed that the elevator had jammed as a result of a loosened eyebolt and did not come loose again until 15 m above the ground.

Third machine

Top view of the third model built

After losing the second machine, Cedric Lee came to the conclusion that the V-position in particular contributed to the insufficient stability of the construction, as it was actually designed in such a way that it should be inherently stable, even without an additional V-position. The wing of the third machine was only given a V-position of 1.5 ° and was probably based on the wind tunnel model No. 17, but received a heavily modified trailing edge. Even after losing the second machine, Lee told Flight magazine that he was still sticking to sending two planes to the Gordon Bennett race. These should have a 90-hp Austro-Daimler six-cylinder engine and a wingspan of just 5 m.

Records of flights by this machine are sparse, but it is known that Gordon Bell operated it until the beginning of the First World War. It was probably with this aircraft that he gave a spectacular flight demonstration in front of Winston Churchill, then First Lord of the Admiralty , and Sir John French. Churchill is reported to have noted:

"How strange it would be if the solution to the problem of flight were presented in the form of a wheel."

- How strange it would be if the solution of the problem of flight presented itself in the form of a wheel!

The Gordon Bennett race, which was scheduled from September 27 to 28, 1914, could not be carried out because the war had started, and Gordon Bell was also called up, so that Cedric Lee was now without a test pilot. In August 1914, he made a flight attempt himself, which ended in a fall from 50 m into the Adur River . Lee survived and was able to swim to shore. After this further setback, Lee stopped further work; he had spent a total of £ 17,000 during the 3.5 year development period.

Aftermath

Lee then enlisted for military service and was employed in the Royal Naval Division and the Royal Naval Volunteer Reserve. He fell at Beaumont-Hamel in August 1914 at the age of 34 . After the war, Richards took on a position as a designer in the aircraft division of the Scottish company Beardmore , which he held until the division was closed in 1921. He continued to work on the development of his ring wing concept, so during his time at Beardmore he patented his idea of designing the wing as a polygon made up of individual spar elements instead of being built on two tubular rings.

Immediately after the armistice, with the conviction that all aerodynamic and structural problems had now been overcome, he approached General Ralph Kirkby Bagnall-Wild , the head of the Aeronautical Inspection Directorate , with the request to finance a test aircraft according to his ideas. The main advantages over conventional designs were the large wing area in a small space (very low aspect ratio ), the high level of automatic stability, great safety for the crew in the event of an accident due to the surrounding wing, the good-natured stall properties and the low landing speed Bagnall-Wilde promised to finance the aircraft through the Air Ministry , but after his retirement his successor AMS Outram refused to honor this obligation.

Even during his subsequent work as an employee of the Science Museum from 1928 to 1955 and later as a teacher at this museum, Richards remained an advocate of his idea of a ring-winged wing. He died in 1960 at the age of 75. The last remaining member of the team was Eric Cecil Gordon England, who died in 1976 at the age of 84.

literature

Philip Jarrett: Circles in the sky, Part 1 . In: Airplane Monthly September 1976, p. 493 ff.
Philip Jarrett: Circles in the sky, Part 2 . In: Airplane Monthly October 1976, p. 526 ff.

Web links

Individual evidence

↑ Mentioned in Flight on May 2, 1954 as "The original Flying Saucer"
↑ Photo of the replica of the Kitchen Ringflüglers on www.airliners.net ( Memento from December 26, 2013 in the Internet Archive )
↑ Crash with Bell at the wheel in Flight from (accessed November 17, 2013)
↑ Cedric Lee's death report in Flight dated November 30, 1916 (bottom left on the page) (accessed November 17)

[1] Mentioned in Flight on May 2, 1954 as "The original Flying Saucer"

[2] Photo of the replica of the Kitchen Ringflüglers on www.airliners.net ( Memento from December 26, 2013 in the Internet Archive )

[3] Crash with Bell at the wheel in Flight from (accessed November 17, 2013)

[4] Cedric Lee's death report in Flight dated November 30, 1916 (bottom left on the page) (accessed November 17)