The explanation of flight most people were taught is wrong
Plenty of textbooks say that a wing is curved on top, so the air going over has further to travel, has to speed up to meet the air underneath, and the faster air presses down less. It is a tidy story and it is not true. Nothing makes the two flows meet up again, and if the theory were right, a plane could never fly upside down — which display pilots do at every airshow.
What actually happens is simpler. WINGS are tilted slightly nose-up, and their shape and angle throw a great deal of air downwards. Push air down hard enough and it pushes back, lifting the aircraft. A flat sheet held at an angle produces lift too; the famous curved shape mostly makes it happen more efficiently and with less drag.
The Wright brothers' real breakthrough
By 1903 other people had built engines, and other people had built wings. The Wright brothers' first powered flight covered 37 metres in twelve seconds, shorter than a modern airliner, but the reason they are remembered is that they solved steering.
Their BIPLANE could be controlled about all three axes: pitch to point the nose up or down, yaw to swing it left or right, and roll to tip one wingtip down. They twisted the whole wing with wires to roll, and they worked it out by building a wind tunnel in their bicycle shop and testing two hundred wing shapes in it. Every aircraft since, from a GLIDER to an AIRBUS, is controlled the same three ways.
The black box is orange
Aircraft carry two recorders: one storing the flight data, one recording the COCKPIT voices. They are painted bright orange, because the point is to find them in wreckage or floating in the sea. 'Black box' was a nickname that stuck.
An Australian scientist, David Warren, built the first one in the 1950s after investigating a crash and thinking how much easier it would be if someone had recorded what happened. His idea was ignored for years before Australia made the recorders compulsory. A modern unit is built to survive an impact of thousands of times the force of gravity and an hour in a fire.
Why flying got safe
Air travel is now extraordinarily safe, and that is mostly a matter of stubborn bookkeeping. Every accident is investigated, every finding turns into a rule or a checklist, and those changes apply to every airline in the world. The recorders, the training, the maintenance schedules and the RADAR screens tracking each aircraft are all pieces of the same machine.
The engines helped too. A modern JET is a turbofan: a huge fan at the front sends most of its air around the outside of the core rather than through it, which is quieter and far more efficient than the early jets that screamed their way off the RUNWAY in the 1950s.
Cruising ALTITUDE is chosen for the same reason. Eleven kilometres up, the air is thin enough to cut drag dramatically and the weather is mostly below you — but far too thin to breathe, so the CABIN is pumped up to roughly the pressure you would feel on a mountain a couple of kilometres high. That is why your ears pop, and why a crisp packet swells on the tray table.