Some of the earliest flapping-wing devices were powered by rubber band. The first successful models were built in the 1870s, with the goal of figuring out a way for people to fly. Information gained from rubber-powered ornithopters likely did contribute to the success of Schmid's manned ornithopters in the 1940s. However, the rubber-band-powered ornithopter became a fascinating hobby in its own right, which offers enjoyment and education for many people to this day.

In 1871, Jobert flew an ornithopter powered by a stretched rubber band turning a crank. In the following year, he built a biplane ornithopter with the twisted rubber band motor more common today. The use of four wings was a clever innovation that reduced the amount of torque needed to flap the wings. The other ornithopters shown here were built by Alphonse Penaud and Hureau de Villeneuve, respectively, in 1872.

In 1874, Victor Tatin devised a more complicated crank mechanism that actively drove the twisting of the wings. His ornithopter shown here is on exhibit at the National Air & Space Museum in Washington. Most of the mechanism was fashioned from bent wire, and it is quite interesting to examine up close. A similar mechanism was used by Pichancourt in his toy bird, "l'oiseau mécanique". This was perhaps the first commercial venture involving ornithopters. Pichancourt is shown at right with his assistant and a rather large rubber-powered ornithopter.

Working around 1890, Lawrence Hargrave discovered that his large rubber-powered ornithopters seemed to fly better if he used small flapping wings together with a larger fixed wing. (below, left) If you double the size of an ornithopter, the scaled rubber band will produce eight times more torque. Unfortunately, you will need sixteen times more torque to flap the wings. Hargrave's approach was the easiest solution, and it was used by many others over the next hundred years.

Alexander Lippisch led a group of aviation students during the 1930s. He and his students built many large ornithopters powered by rubber band and by internal combustion engines. The science of aeronautics had advanced greatly since Hargrave, and the Lippisch ornithopters showed similar progress, though the flapping wings remained comparatively small.

Erich von Holst experimented with various bird and dragonfly ornithopter configurations in the 1930s. His work included experimentation with biplane wing phasing and hinged outer wing panels. Some of his rubber-powered ornithopters achieved a very high level of realism, as in the example shown above.

Indoor ornithopter contests began in the 1930s. A model airplane club called the Chicago Aeronuts was holding various contests for the indoor flying of model airplanes. For some extra challenge, they decided to add ornithopters to the list of events. Ed Lidgard's design shown here could be built from magazine plans, and many of the models built over the subsequent decades followed a similar pattern.

In the 1980s, it was found that biplane ornithopters had a huge advantage in these indoor flying contests. With the right timing of the wings, it became possible to extract far more useful work from the rubber band. A more uniform crank motion also allowed a more efficient upstroke. The lifting upstroke of one wing would help drive the downstroke of another wing, reducing the torque and power required to fly the ornithopter. The smoother flapping motion also allowed overall weight reduction.

Another modification was to move the stabilizer to the front of the model. Previously, a long tail boom had been necessary, in order to support the weight of the rubber band and motor stick. The forward stabilizer supported the load more efficiently with less structural weight.

With these innovations, ornithopter flight times increased from around four minutes, to the current record of 21 minutes, 44 seconds held by Roy White. Successful competition models are extremely light-weight and delicate. Careful adjustments must be made to maximize the flight time without hitting the ceiling. Perhaps as you refine your ornithopter skills, you will be able to log some impressive flight times of your own.

The rubber-band-powered ornithopter also offers a range of interesting projects, aside from duration contests. Shown above: Ken Johnson's lifelike butterfly model. John White's ornithopter in which the tail moves along with the wings. Albert Kempf's dragonfly using a geared rubber band motor and foam wings.