Transferable Technology: From the Bicycle to the Aeroplane and the Car

Orville Wright and Edwin H. Sines, neighbour and boyhood friend, filing frames in the back of the Wright bicycle shop at 1127 West Third Street, Dayton, Ohio, 1897.

Before Orville and Wilbur Wright gained fame as the first people to make a controlled, powered and sustained heavier-than-air human flight they owned and ran a bicycle repair, rental and sales company in Dayton, Ohio, under the name the Wright Cycle Exchange, where they sold many brands of bicycles, including Fleetwing, Reading, Coventry Cross, Envoy, Smalley, Warwick, Duchess, and Halladay-Temple. In the latter part of 1895 they changed the name to the Wright Cycle Company and from April 1896, the Wright brothers produced their own bicycles under the brand names Van Cleve and St Clair. These were built from suppliers components rather than tooled by the Wright brothers themselves, with frames for their bicycles sourced from the Pope Manufacturing Company and other parts selected by the brothers to meet their exacting standards. They did, however, come up with two important innovations in the development of the bicycle, the self-oiling hub and the machining of the left hand crank and pedal with a left hand thread to stop them from coming unscrewed while cycling.

The Van Cleve from the Wright Brother 1900 Catalogue

As everyone knows Orville and Wilbur went on to become the fathers of powered flight. From 1899 to 1901 the brothers experimented with designs for a glider with varying levels of success. Despite utilising accepted calculations and lift and drag data their designs had not performed as well as would be expected were the calculated predictions correct. It was here that the bicycle proved to be of assistance when they mounted a wheel horizontally above the front wheel of one of their St Clair bicycles to study airfoil design and to compare the forces acting on two objects with different shapes.

The Wright Brothers bicycle apparatus

At first the brothers had attempted to make their measurements by mounting the test surfaces on a stationary wheel but found it impossible to obtain satisfactory results through the effect of natural wind alone. By mounting the wheel on the front of a bicycle they were then able to ride at various angles to the wind to obtain their data. From their test results they were able to determine that John Smeaton’s pressure coefficient, which measured the drag on a one foot square flat plate moving at one mile per hour, was inaccurate. Orville and Wilbur replaced Smeaton’s coefficient figure of .005 with their own findings of .0033, a figure that was very close to the coefficient of .00327 accepted today.

Encouraged by their findings the brothers embarked on a series of wind tunnel tests. With the fan located at one end of the 6 foot long tunnel air flow was inevitably turbulent and to counter this they constructed a series of balances made from old hacksaw blades and bicycle spokes that could be carefully positioned in the tunnel to smooth the air flow. Throughout the winter of 1901 Orville and Wilbur carried out test after test on different wing shape models, resulting in the most detailed data then available in the world for the design of aircraft wings.

By 1903 the brothers had constructed their first powered aircraft, the Wright Flyer I. Built with a frame of lightweight spruce and with wing coverings made from Pride of the West muslin. The plane was powered by an engine they had built themselves after determining that no manufacturer supplied one that was both light enough and that provided enough horsepower. As with their glider designs and testing program Orville and Wilbur turned to bicycle technology to provide solutions and material. Bicycle spoke wire was used to brace the wings, and bicycle chains and sprockets of varying sizes were used to turn the camshaft that operated the engines spark breaker arms and exhaust valves, to turn the propellers, and to provide linkages to control systems. Their 1905 Wright Flyer III made use of an oversized bicycle hub that rode the launch rail  to ensure that the plane stayed in a straight line during take off.

Gear and bicycle chain used to drive the propellers

It may be too great a claim to state that the aeroplane owes its birth to the bicycle but it does owe its more humble transport cousin a huge debt. Unlike the other revolutionary transport technology of the Nineteenth Century, the railway engine, bicycles demanded strong but lightweight structures, and bicycle chains and sprockets offered an effective drive system that could provide transmission without too great a weight sacrifice; essential for a successful aircraft. Elsewhere it was the demand for bicycles that drove the innovative work of men such as Jules Suriray, the inventor of the the first radial style ball bearing, James Starley, the inventor of the chain-drive differential, William Ford Robinson Stanley, the inventor of steel-wheel spider spokes and Eugene Meyer the inventor of the tensioned wire bicycle wheel. Not to mention two-speed drives, hubs, chain and sprocket transmission systems, butted tubes, and a host of other innovations that were inspired by the bicycle but went on to be used in the aeronautical and automotive industries.

Orville and Wilbur Wright’s familiarity and technical competence with bicycles paid dividends when they turned their serious attention to the problem of powered flight. Not least because the bicycle offered a conceptual lesson in that it demonstrated that controlled movement could be achieved despite the inherent instability of the machine, a key concept in aeroplane design, but also because the engineering and mechanical challenges of good bicycle design meant that men like the Wright brothers and Karl Benz, the inventor of the first automobile powered by an internal combustion engine, were able to build on and adapt the innovations that had led to the lightweight, reliable, and mechanically efficient safety bicycle.

Cyclists of a certain age or inclination will be well aware of the famous bicycle frame tubing brand, Reynolds, the company who pioneered double-butted tubing in 1898. Reynolds 531, introduced in 1935, was the standard for excellence in bicycle frame building for decades and the properties of steel continue to make it a rival for today’s carbon and alloy frames, not least due to its greater longevity and strength. Reynolds 531 is another bicycle design component that has been used in the automotive industry, most famously for the chassis of the record breaking jet propelled car, Thrust 2, which held the world land speed record from 1983 to 1997 by reaching 633.468 miles per hour. It, and other Reynolds tubing products, have also been used in aircraft production, sports car and motorbike chassis’ and frames, competition wheelchairs, and NASA projects.

The crossover between technologies has worked in both directions. Mike Burrows’ famous Lotus 108 carbon fibre bicycle owed its design and construction to the development of carbon fibre composite materials by Royal Air Force engineers in 1963, and to Burrows’ familiarity with aerodynamics and drag coefficients. Carbon fibre has gone on to be the material of choice for many manufacturers of bicycle frames and components. But it was not until 2009, seventeen years after the Lotus 108 was built, that Boeing produced the first aircraft with carbon fibre wings, the 787 Dreamliner. Elsewhere the successful brand of Fulcrum wheels and hubs is the brain child of three Italian aeronautical engineering students who happened to love cycling and designed a new type of hub and bearing as part of their university degree.

More recently, the British sports car company Caterham Cars has announced a partnership with Reynolds to design and build a new lightweight frame using Reynolds tubing. The Caterham-Reynolds partnership is another reminder of the central role the bicycle and its development has played in the history of modern transport through the transfer of technology.