airand.space

Design studio · 1903

Build your own flying machine

Choose wings, engine, propellers, and a way to steer. Watch the four forces change. Then put your machine on the rail at Kill Devil Hills and find out how far it goes.

Reading level

In 1903 there was no catalog of airplane parts. The Wrights had to decide everything: how big the wings should be, how curved, how many, what engine, what propellers, and how the pilot would steer. Every choice changed the weight, and every pound of weight needed more lift.

Here you get the same choices. Change one thing at a time and watch the numbers. Then put your machine on the rail at Kill Devil Hills and see how far it goes.

This is a design problem with four forces and a budget. Lift must beat weight; thrust must beat drag; and every part you add to get more lift or thrust adds weight. The model uses the Wrights' own lift equation, L = k·S·V²·C_L, with a simplified lift coefficient, a parasite-plus-induced drag estimate, and propeller thrust falling off with speed.

Set the parts, read the flying speed and the thrust margin, and launch into the headwind. The result is compared with the four real flights of December 17, 1903.

Parts

Wings
Engine
Propellers
Pilot
Control
The day

In 1901 the Wrights trusted the published tables and their glider made far less lift than promised. Switch this on to see your design the way the old books would have predicted it.

The 1890s tables used Smeaton's coefficient k = 0.005; the Wrights' measurements pointed to about 0.0033. Switch this on to compute with the old value and compare: a design that flies on paper may not fly on the sand.

On the sand

A simplified teaching model: a point-mass flight with the pilot holding the chosen angle, the Wrights' lift equation with a calibrated lift coefficient, and the two historical limits (a few seconds without a control system, 59 seconds with one). Distances are over the ground, into the wind, like the 1903 measurements.

Your drawing

Every real flying machine started as a drawing. Name yours, pick a fabric, and print the drawing for the wall. The numbers on it are your design.

The drawing is generated from your parameters, in the style of a patent sheet: plan and side views with the dimensions you chose. Save it as an SVG file to open in any drawing program.

Generated from your choices. Nothing is uploaded; the link to a design is just the numbers in the web address.

Now build one you can hold

The Wrights tested on paper, then in the wind tunnel, then on the sand. Do the same: fold two paper gliders that differ in one thing, measure how far they glide, and compare with what the studio predicts for a glider.

The paper glider test, printable →

For teachers

Goals

  • Explain lift, drag, thrust, and weight as four forces that must balance for level flight.
  • Show that engineering is tradeoffs: more wing adds lift and drag and weight at the same time.
  • Use a measured number (the corrected Smeaton coefficient) to see why the 1901 glider failed.
  • Connect a design on screen to a physical model that students build and measure.

Discussion questions

  1. Make the wings as big as the sliders allow. Does the machine fly better? Why not always?
  2. Try the 52-horsepower engine with no control system. What happens, and what does that tell you about Langley's Aerodrome?
  3. Turn the wind down to zero. Why did the Wrights wait for a windy day?
  4. What is the lightest machine you can design that still makes a real flight?
  1. Hold everything fixed and vary only the chord. Plot flying speed against chord. What shape is the curve, and why?
  2. At the flying speed, compare thrust and drag for each engine. Which engine gives the largest margin per pound?
  3. Switch to the old tables. Find a design that flies under the old tables and not under the corrected ones. What would that have cost a 1901 experimenter?
  4. Using the glide-ratio data from your paper gliders, estimate their lift-to-drag ratio and compare it with the model's number for a glider of the same aspect ratio.

Pairs with the Kitty Hawk chapter and its wind tunnel. Educators who want to build on the source code can email education@czerwonkalegal.com.

Sources and what is simplified

  1. 1903 Wright Flyer, object record, Smithsonian National Air and Space Museum. Span 40 ft 4 in, weight 605 lb, 12 hp engine, flights of December 17.
  2. Manly–Balzer engine, object record, Smithsonian National Air and Space Museum. About 52 hp for 125 lb; Langley's Aerodrome, 1903.
  3. Orville Wright, “How We Made the First Flight,” Flying, December 1913, Public domain. Wind, the rail, the four flights, and the engine's story.
  4. Wilbur Wright, “Some Aeronautical Experiments,” 1901, Western Society of Engineers; public domain. The lift tables, Smeaton's coefficient, and the 1901 disappointment.
  5. Orville Wright's diary, December 17, 1903, Library of Congress, Wilbur and Orville Wright Papers. Wind readings and the flights as recorded that day.

The catalog engine is a typical 1903 figure (about 30 lb per horsepower), not a specific product. Structure weights per square foot, propeller efficiencies, drag figures, and the lift coefficient are teaching estimates, calibrated so the real 1903 Flyer behaves as the record says: about 30 mph of airspeed to fly, a marginal thrust surplus, no takeoff from the 60-foot rail in calm air. airand.space is independent and not affiliated with the Smithsonian Institution, the Library of Congress, or the Wright family.