⌛🪶 Modern Airflight: The Birth of Powered Flight
The Dawn of Modern Aviation
In the pursuit of flying in the sky, we saw in the previous part, how we reached the period of airships — the big cigar-shaped steerable balloons.
Why move beyond Airships?
Airships were indeed a decent means of transportation. Although nowadays it is used only for recreational purposes, the airships were used in both WWI and WWII. These steerable balloons posed a few limitations like having limited payload capacity and accommodating only a few dozen passengers at most.
Their endurance typically ranged from a few hours to a day. This coupled with their slow speeds, vulnerability, and extended start-up times, generated the necessity for the invention of something better.
Now, remember that both of these aviation wonders — balloons, and airships used the principle of buoyancy to fly. The term “lighter-than-air” refers to these aircraft because their ability to float and stay aloft is made possible by using gases that are less dense than the air they displace, resulting in an upward buoyant force. They didn’t “generate” lift, unlike kites.
Heavier-than-air Aircraft
While the format of the article might suggest that the development of heavier-than-air aircraft came after the lighter-than-air aircraft, that’s not the case. A lot of work for these heavier machines was going on in parallel. In fact, the first man-made aircraft — a kite, was indeed a heavier-than-air aircraft that flew by generating lift.
The problem with Kites was that it needed high wind speed to work and the only way to make it powerful enough to carry a man was to use a lot of them together (or use very large ones).
The fundamental need to have sufficient relative wind velocity (and keeping overall weight low) was the hindrance that had to be solved. Kites used high wind speed to solve this. And to overcome its limitations humans started working on increasing the speed of the craft (or rotor or wings) relative to still air.
Sir George Cayley helps us in Gliding!
In 1799, Sir George Cayley introduced the idea of a modern airplane. He envisioned it as a fixed-wing flying machine with separate parts for lift, propulsion, and control. Cayley began creating and testing models of fixed-wing aircraft in 1803.
Cayley laid out the principles of heavier-than-air flight, was one of the first to scientifically understand the principles of bird flight and also gave the important principles of power-to-weight ratio in sustaining flight. He was the first to present and explain the need for balancing four vector forces that influence an aircraft: thrust, lift, drag and weight.
He defined the modern aeroplane configuration comprising a fixed-wing, fuselage (airplane’s main body section that holds crew, passengers, or cargo) and tail assembly. If this was not enough, he also demonstrated manned, gliding flight.
“About 100 years ago, an Englishman, Sir George Cayley, carried the science of flight to a point which it had never reached before and which it scarcely reached again during the last century.”
— Wilbur Wright, 1909.
The model glider successfully flown by Cayley in 1804 had the layout of a modern aircraft, with a kite-shaped wing towards the front and an adjustable tailplane at the back consisting of horizontal stabilisers and a vertical fin. A movable weight allowed adjustment of the model’s centre of gravity.
In 1848, Cayley constructed a glider in the form of a triplane large and safe enough to carry a child. A local boy was chosen but his name is not known. (Unlucky boy… could’ve been part of history books!)
He went on to publish in 1852 the design for a full-size manned glider or “governable parachute” to be launched from a balloon and then to construct a version capable of launching from the top of a hill, which carried the first adult human in 1853.
For all his important contributions, Sir George Cayley is often referred to as the father of airplane.
In 1856, Frenchman Jean-Marie Le Bris made the first flight higher than his point of departure, by having his glider “L’Albatros artificiel” pulled by a horse on a beach. He reportedly achieved a height of 100 meters, over a distance of 200 meters.
First controlled flights by John J. Montgomery
In 1884, an American named John J. Montgomery conducted controlled flights in a glider as part of a series of gliders he built between 1883 and 1886. Montgomery devised different control methods for his gliders, including weight shifting for roll and an elevator for pitch. Subsequent designs used hinged, pilot-operated trailing edge flaps on the wings (1885–1886) for roll control, and later, full wing warping systems for roll (1903–1905) and for both pitch and roll (1911).
Unfortunately, in 1911, while attempting a low-speed landing of the “Evergreen” glider, Montgomery encountered turbulence, resulting in a stall (an aerodynamic condition that leads to a sudden reduction in lift force), that led to a fatal crash and his subsequent death from injuries at the scene.
Otto Lilienthal: The Glider King
Otto Lilienthal, known as the “Glider King,” made significant contributions to aviation history. In 1884, he expanded on earlier research and published the influential work “Birdflight as the Basis of Aviation.”
He also produced a series of hang gliders, including bat-wing, monoplane and biplane forms, making his firm the Maschinenfabrik Otto Lilienthal the first air plane production company in the world.
Starting in 1891, he became the first to routinely make controlled untethered glides and the first to be photographed in flight, marking the beginning of human flight. His meticulous documentation of his work and over 2,000 glides earned him the titles “father of aviation” and “father of flight.”
Tragically, similar to John Montgomery, he passed away in 1896 due to injuries from a glider crash.
Race to first powered-controlled-manned flight.
From flying kites to carrying oneself on slow drifting balloons to controlled airships to faster-and-controlled gliders humanity had made a great progress already.
Just one last piece of the puzzle had to be solved.
Most of the gliders were carried forward either on some fast-moving animal like a horse or the pilot rode down the hill gaining velocity and then becoming airborne. This wasn’t just the practical way going forward.
We needed a machine that could power itself, and generate lift sufficient enough to carry a man. Just one man was enough for now! And yes, the flight should be controllable.
While many people have contributed and made serious efforts to solve this problem, we will discuss the efforts of two great pioneers of airplanes.
Samuel Pierpont Langley
Samuel Pierpont Langley was an American aviation pioneer. His experiments in aerodynamics were documented in “Experiments in Aerodynamics” published in 1891.
On 6 May, 1896, Langley’s Aerodrome №5 achieved the first sustained flight of an unpiloted, engine-driven heavier-than-air craft of significant size, launching from a houseboat on the Potomac River. Two flights were made that afternoon, one of 1,005 metres and a second of 700 metres, at a speed of approximately 40 km/h.
On both occasions, the aircraft landed in the water as planned, because, in order to save weight, it was not equipped with landing gear. Subsequent successful flights, including one witnessed by Alexander Graham Bell, followed.
Langley sought funding for a full-scale, human-carrying version of his designs, and received $50,000 from the U.S. government and another $20,000 from the Smithsonian Institution. He designed a full-size man-carrying airplane and named it as Aerodrome A. For testing he manufactured a one-fourth scaled down version of Aerodrome and flew it twice in 1901 and 1903. Despite initial successes, challenges emerged.
While the tests with the scaled-down version went great, the problem came in scaling up. The full-scale version when coupled with a powerful engine ended up being very fragile structurally and both of its two launches in late 1903 ended with the Aerodrome immediately crashing into the water and the pilot being rescued each time.
Important to consider the dates of the two launches: October 7 and December 8, 1903. We will come back to this in a moment.
Langley’s attempts to gain further funding failed, and his efforts ended.
Wright Brothers: Showing how it is done!
Orville Wright and Wilbur Wright, famously referred to as the Wright Brothers were American aviation pioneers who differentiated their work from contemporaries by being more methodical and experimental in their approach. While others focused on making new iterations of airplanes as soon as possible, the Wright brothers made dedicated efforts to obtain empirical data, doing experiments, finding root causes of failures and then doing modifications to their flight attempts.
This is apparent when you consider the fact that the Wrights constructed their own wind tunnel and created a number of sophisticated devices to measure lift and drag on the 200 wing designs they tested. This was done after realising that the gliders built by them were not generating enough lift (as per their calculations). Their first full-size glider, launched in 1900, had only about half the lift they anticipated. Their second glider, built the following year, performed even more poorly.
Wilbur makes a turn using wing-warping and the movable rudder, October 24, 1902.
They invented wing-warping for roll control, wooden propellers, low-powered internal combustion engine, and laid a great emphasis on not leading safety to chance. Combing all of these they invented and built the Wright Flyer and made the first sustained flight by a manned heavier-than-air powered and controlled aircraft — an airplane — on December 17, 1903. This was just 9 days after Langleys second and last attempted flight.
- First Flight (Wilbur Wright): Wilbur won the coin toss and piloted the first attempt on 14th December, 1903. The aircraft left the rail but stalled after covering 32 meters in 3.5 seconds, sustaining minor damage.
- First Successful Flight (Orville Wright): After three days of repairs, Orville took the controls on December 17. Facing wind speeds exceeding 20 mph, the aircraft was positioned into the wind. Orville’s flight lasted 12 seconds, covering 37 meters.
- Series of Flights: The Wrights took turns flying, completing four low-altitude flights that day. The flights were essentially straight with no attempts at turning. The last flight, piloted by Wilbur, covered 260 meters in 59 seconds, surpassing the previous shorter flights.
This initial flight would set in motion an era of rapid advancements, driven in part by the crucible of two world wars, ultimately transforming airplanes into the incredibly safe and efficient mode of travel that we experience today. As we have seen in the article, many brave souls dedicated their lives and, in some cases, paid the ultimate price in pursuit of this lofty vision, helping make airplanes one of the safest modes of travel.
So, I hope when you travel next time by flight, may you carry with you a piece of this captivating tale of aviation’s evolution.
