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Physics of flight: questions and answers

Physics of flight: the most searched Aviation questions, with a direct answer, an explanation and sources.

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  Physics of flight

  Why do planes require airplane mode?

  Airplane mode is required because a phone hunting for a distant ground tower transmits at full power, and regulators like the FCC and EASA want to rule out… more…

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  Physics of flight

  Why do jet engines not melt?

  Turbine inlet gas can exceed 1,600 °C, above the melting point of the nickel superalloys in the blades, yet they survive because the metal never touches that… more…

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  Physics of flight

  How high does the F-16 fly?

  The F-16 has a service ceiling above 15,240 m (50,000 ft), according to the USAF's official fact sheet. In real operation it flies much lower: patrols and air… more…

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  Physics of flight

  How fast does the F-16 fly?

  The F-16 Fighting Falcon reaches over Mach 2 at altitude, about 2,400 km/h (1,500 mph), according to the U.S. Air Force's official specs. In real missions it… more…

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  Physics of flight

  What happens when a plane goes supersonic?

  When an aircraft passes Mach 1 the air can no longer move out of its way in advance, so pressure disturbances pile up into shock waves at the nose, wings and… more…

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  Physics of flight

  Why is the speed of sound so slow?

  Sound is slow because it is a push, not a signal: air molecules must bump into their neighbours to pass the pressure wave along, and they do so at roughly… more…

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  Physics of flight

  Why does a plane keep circling?

  A circling aircraft is usually holding: air traffic control has asked it to fly a racetrack pattern while a runway, a weather cell or a traffic gap clears… more…

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  Physics of flight

  What is aircraft fuel?

  Aircraft fuel par excellence is Jet A-1, an aviation kerosene burned by all jets and turboprops, from the A320 to the 747; in the United States it's… more…

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  Physics of flight

  Where is the speed of sound greatest?

  The speed of sound is greater in solids than in liquids, and greater in liquids than in gases: about 5,900 m/s in steel, 1,480 m/s in water, and 343 m/s in… more…

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  Physics of flight

  How do supersonic planes work?

  A supersonic aircraft is built to live with shock waves. Thin, sharply swept or delta wings and a slender fuselage keep wave drag low; intakes with movable… more…

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  Physics of flight

  How does the speed of sound change with altitude?

  The speed of sound depends only on air temperature, not on pressure or density, so it falls as the troposphere cools: about 340 m/s (661 kn) at sea level in… more…

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  Physics of flight

  What are supersonic planes?

  Supersonic planes are aircraft that fly faster than the speed of sound, above Mach 1, about 1,060 km/h (573 kn) at cruise altitude. Most are military… more…

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  Physics of flight

  Why do contrails form?

  Contrails form when hot, humid exhaust from jet engines meets air that is cold enough, typically below about −40 °C at cruise altitude, for the water vapour… more…

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  Physics of flight

  Why does an airplane fly?

  An airplane flies because its wings turn the oncoming airflow downward, and the air pushes back with an upward force called lift. The wing's shape and angle… more…

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  Physics of flight

  When was the autopilot invented?

  The first autopilot was developed in 1912 by Elmer Sperry's company: a gyroscopic stabilizer that kept the aircraft level. His son Lawrence Sperry… more…

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  Physics of flight

  Why did the Royal Aircraft Establishment ask Airspeed to fit flaps and air brakes to its Courier?

  Because the Courier was so aerodynamically clean that, once in the air, it was very hard to bring back down. Thanks to that advanced aerodynamics the Royal… more…

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  Physics of flight

  Why do jet engines use kerosene?

  Jet engines burn kerosene because it packs about 43 MJ/kg into a dense, cheap, easy-to-store liquid that stays fluid down to −47 °C (Jet A-1) and does not… more…

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  Physics of flight

  What are aircraft engines like?

  Aircraft engines fall into two main families: piston engines, which drive a propeller and power light aviation, and gas turbines, which compress air, burn it… more…

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  Physics of flight

  What fuel do planes use?

  Jet and turboprop aircraft burn aviation kerosene — Jet A-1 almost everywhere, Jet A in the United States; the military use variants such as JP-8. Light… more…

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  Physics of flight

  How did the pressure carburetor put an end to R-2800 engine cutouts in inverted flight?

  The fix was removing the float: the pressure carburetor meters fuel very precisely, prevents icing, and avoids fuel starvation under negative load factor and… more…

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  Physics of flight

  How was the NF-104A controlled once the rudders stopped working?

  With a reaction control system, because in the thin air of the high stratosphere the normal control surfaces had little or no effect. It consisted of eight… more…

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  Physics of flight

  How fast does a supersonic plane fly?

  A supersonic aircraft flies faster than Mach 1, around 1,060 km/h (660 mph) at cruise altitude. Concorde cruised at Mach 2.04, about 2,180 km/h at 18,000 m… more…

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  Physics of flight

  What is aviation fuel?

  Aviation fuel is a petroleum-refined kerosene, manufactured under the Jet A-1 or Jet A specifications: a blend of hydrocarbons with 8 to 16 carbons, a flash… more…

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  Physics of flight

  At what altitude do airplanes fly?

  Commercial jets cruise between 9,000 and 12,000 m (30,000-40,000 ft); regional turboprops between 5,000 and 8,000 m; propeller light aircraft rarely exceed… more…

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  Physics of flight

  How does the speed of sound vary with temperature?

  The speed of sound in air rises with the square root of absolute temperature: about 340 m/s (661 kn) at 15 °C at sea level, falling to about 295 m/s (573 kn)… more…

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  Physics of flight

  Why can planes fly?

  A plane flies because its wings, moving forward fast enough, deflect air downward and generate an upward force, lift, that matches or exceeds its weight. The… more…

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  Physics of flight

  Why do the wing engines of the Ju 52/3m appear angled outward?

  Because they were mounted almost perpendicular to the wing's swept leading edge, rather than parallel to the fuselage. Seen from above, the Ju 52/3m's two… more…

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  Physics of flight

  Why does the speed of sound change with altitude?

  The speed of sound changes with altitude because it depends on air temperature, and temperature falls as you climb through the troposphere. Colder molecules… more…

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  Physics of flight

  Why is the sound barrier?

  There is no physical wall in the air: the sound barrier is the sharp rise in drag and loss of control that early aircraft met near Mach 1, when shock waves… more…

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  Physics of flight

  What is "flight envelope protection," which the A320 pioneered?

  A set of limits embedded in the flight control software: it calculates the flight envelope, adds a safety margin, and blocks pilot inputs that would take the… more…

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  Physics of flight

  Where is airplane fuel stored?

  Almost all the fuel sits inside the wings, in integral tanks formed by the structure itself, plus a center tank in the wing box beneath the cabin. Some… more…

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  Physics of flight

  What wind tunnel did NACA use to study the Corsair, and how big was it?

  The full-scale 30- by 60-Foot Tunnel at the Langley Research Center, in Hampton, Virginia. NACA dedicated the facility on 27 May 1931 and used it to test the… more…

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  Physics of flight

  How long do contrails last?

  Contrails last anywhere from a few seconds to several hours. In dry air at cruise altitude the ice crystals sublimate almost immediately; when the surrounding… more…

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  Physics of flight

  Why are supersonic planes banned?

  Supersonic aircraft are not banned; what is prohibited is civil supersonic flight over land in the United States (since 1973) and many other countries… more…

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  Physics of flight

  What was the Ju 52's "Doppelflügel"?

  It was the name given to the narrow control surface that ran along the entire trailing edge of the Ju 52's wing, set apart from it. Its inboard section acted… more…

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  Physics of flight

  Why do planes float?

  An airplane doesn't float like a balloon: it's far heavier than the air it displaces. It stays up because the wings, moving forward, deflect air downward and… more…

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  Physics of flight

  How much cruising speed did the Airspeed Courier gain by retracting its undercarriage?

  About 32 km/h (20 mph) of cruising speed. Sources attribute the gain to the lower drag with the main wheels retracted, at the cost of roughly 30 lb for the… more…

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  Physics of flight

  What is the speed of a supersonic aircraft?

  A supersonic aircraft flies faster than Mach 1, meaning more than 1,062 km/h at cruise altitude (1,225 km/h at sea level). Concorde cruised at Mach 2.04… more…

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  Physics of flight

  Why do planes break the sound barrier?

  A plane breaks the sound barrier when it exceeds the speed at which the pressure waves it itself generates propagate, about 340 m/s (1,225 km/h) at sea level… more…

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  Physics of flight

  How does a plane fly?

  A plane flies by using engine thrust to move its wings through the air fast enough to generate lift greater than or equal to its weight. The wing's shape and… more…

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  Physics of flight

  Why does the speed of sound vary with temperature?

  Sound is a pressure wave passed along by molecular collisions, so it travels faster when molecules move faster, and molecular speed is set by temperature. In… more…

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  Physics of flight

  Who discovered the speed of sound?

  No one discovered it all at once. Marin Mersenne and Pierre Gassendi measured it in the 1630s by timing the flash and bang of gunfire; the Accademia del… more…

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  Physics of flight

  How high planes fly?

  Commercial jets typically cruise between 9,000 and 12,500 m (30,000–41,000 ft), where thin air cuts drag and fuel burn while the engines still get enough… more…

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  Physics of flight

  How fast can Superman fly?

  Superman isn't a real speed: he's a fictional character whose limit changes with every writer, from "faster than a speeding bullet" in 1940 to surpassing… more…

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  Physics of flight

  How far can the b 21 fly?

  The B-21 Raider's range is classified: neither the US Air Force nor Northrop Grumman has published a figure (data of September 2026). The Air Force describes… more…

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  Physics of flight

  What is jet fuel like?

  Jet fuel is aviation kerosene (Jet A-1): a clear, pale-to-straw-colored liquid with a petroleum smell, a density of about 0.8 kg/L, a freezing point of −47 °C… more…

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  Physics of flight

  Are supersonic planes coming back?

  Yes, but not yet for passengers. Concorde retired in 2003; since then Boom's XB-1 went supersonic in January 2025, NASA's X-59 flew in October 2025 to test… more…

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  Physics of flight

  Why do supersonic planes have swept wings?

  Sweep delays and softens the drag rise around the speed of sound. Only the airflow component perpendicular to the leading edge counts for compressibility, so… more…

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  Physics of flight

  How to land an airplane?

  Landing an airplane means descending along a stable path of about 3° toward the runway, with speed, flap setting and landing gear set before reaching 300 m… more…

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  Physics of flight

  Why do planes need air start?

  Most jet engines have no electric starter: the compressor must be spun to around 20-25% of rated speed before fuel is lit and the turbine can sustain itself… more…

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  Physics of flight

  How fast does the Su-57 fly?

  The Su-57 reaches about 2,140 km/h (Mach 2) at altitude according to figures published by its manufacturer, and can sustain supersonic flight without… more…

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  Physics of flight

  What happens if an airplane's engines shut down in flight?

  If an airplane's engines shut off in flight, it doesn't fall: it glides. A commercial jet travels about 15-17 km for every 1,000 m it descends, so from 11,000… more…

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  Physics of flight

  Why does the sound barrier boom?

  The boom is not the aircraft breaking anything: it is the shock waves that any supersonic aircraft drags behind it, heard as a sudden pressure jump when the… more…

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  Physics of flight

  Why do airplanes fly so high?

  Airliners cruise at 9–12 km (30,000–40,000 ft) mainly to save fuel: the air up there is a third to a quarter as dense as at sea level, so drag falls and jet… more…

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  Physics of flight

  Why do planes need airplane mode?

  Airplane mode is required mainly by regulation and caution, not by a proven history of accidents. Regulators such as the FAA and EASA require devices to stop… more…

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  Physics of flight

  Why did supersonic planes stop?

  Concorde stopped flying in 2003 because it no longer paid its way: it burned far more fuel per seat than subsonic jets, carried only around 100 passengers… more…

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  Physics of flight

  Why do the Corsair's wings join the fuselage at a right angle?

  Because of the propeller: with the chosen wing chord it was hard to lengthen the gear legs to clear the large propeller, and the solution was the inverted… more…

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  Physics of flight

  Why do planes board front to back?

  Most airlines do not board front to back for speed: the premium cabin at the front boards first as a commercial perk, and economy then boards by zones, often… more…

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  Physics of flight

  How fast does the F-35 fly?

  The F-35 Lightning II has a top speed of Mach 1.6, about 1,900 km/h (1,200 mph) at altitude, according to Lockheed Martin. That's slower than the F-16 or F-22… more…

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  Physics of flight

  What happens if a plane can't land?

  If a plane can't land at its destination, it diverts to an alternate airport the crew already chose before takeoff and for which it carries extra fuel. In… more…

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  Physics of flight

  What type of flap helped a World War II fighter turn best?

  The slotted flap, the NACA type fitted to the F4U Corsair, with a dedicated 20° maneuver setting usable at 200 knots indicated or less. With it the fighter… more…

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  Physics of flight

  Why are supersonic planes coming back?

  Supersonic airliners are returning because three obstacles are easing: the overland boom ban, which the United States moved in 2025 to replace with a noise… more…

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  Physics of flight

  Why does an airplane stay in the air?

  An airplane stays airborne because its wings produce lift that matches its weight. Moving through the air, a wing turns the flow downward and creates lower… more…

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  Physics of flight

  What flaw sank Vought's all-metal V-141 fighter?

  It wasn't a single flaw: tests showed the V-141 still flew poorly, was prone to spinning, and also suffered tail flutter, which is why it was rejected. It… more…

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  Physics of flight

  What happens if I put airplane fuel in my car?

  Jet fuel (Jet A-1) is kerosene, not gasoline. In a gasoline engine it won't start properly or it runs with knocking, smoke and power loss, and can damage the… more…

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  Physics of flight

  How high up are the wings of an airplane?

  On passenger aircraft the wing sits low on the fuselage: on a Boeing 737 the engine nacelles sit about 46 cm off the ground and the wing root just over a… more…

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  Physics of flight

  Why do planes vanish in the bermuda triangle?

  They do not, at least not more than anywhere else. The US Coast Guard, NOAA and insurers find no higher rate of aircraft or ship losses in the Bermuda… more…

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  Physics of flight

  How high are contrails?

  Contrails usually form between about 8 and 12 km (26,000–40,000 ft), the cruise band of jet airliners, where the air is colder than roughly −40 °C. Below that… more…

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  Physics of flight

  Where were the elevators on the Vulcan B.1, given it had no horizontal stabiliser?

  On the wing's own trailing edge. The Vulcan B.1 had four elevators on the inner section and four ailerons on the outer section; the tail only had a fin and a… more…

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  Physics of flight

  What was the purpose of the Constellation's curved fuselage?

  To raise the tail and keep the fins clear of the propellers' turbulent airflow, while the nose dipped slightly to shorten the nose landing gear leg. That… more…

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  Physics of flight

  How far is the speed of sound?

  The speed of sound is a speed, not a distance: in air at 20 °C and sea level it is about 343 m/s (1,235 km/h, 667 kn), so sound covers one kilometre in… more…

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  Physics of flight

  Why do planes retract their landing gear?

  Planes retract their landing gear to cut aerodynamic drag: wheels, legs and shock absorbers exposed to the airflow slow the aircraft and force it to burn more… more…

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  Physics of flight

  How did the Avro 707B differ from the 707A?

  In the flight regime they studied. The Avro 707B, the second low-speed example, investigated delta-wing handling at low speeds; the 707A was designed as a… more…

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  Physics of flight

  Why does the sound barrier exist?

  The sound barrier exists because pressure disturbances travel through air at the speed of sound. Below Mach 1 the air ahead of an aircraft receives warning… more…

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  Physics of flight

  How does an aircraft's autopilot work?

  The autopilot is a control system that maintains attitude, heading, altitude and speed without manual input. It reads sensors (gyroscopes, accelerometers, air… more…

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  Physics of flight

  Why do planes dump fuel?

  Planes dump fuel only when they must land while still heavier than their maximum landing weight, usually after an engine problem or a medical emergency… more…

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  Physics of flight

  How fast does the B-2 Spirit fly?

  The B-2 Spirit is subsonic: the U.S. Air Force lists its maximum speed as "high subsonic," which in practice is around Mach 0.95, about 1,010 km/h at… more…

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  Physics of flight

  How does a plane stay in the air?

  A plane stays in the air as long as four forces stay in balance: lift from the wings opposes weight, and thrust from the engines opposes drag. In level… more…

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  Physics of flight

  Why do planes just sit in the sky?

  Planes never sit still; a cruising airliner covers about 900 km/h (490 kn). It looks motionless because it is far away: at 11 km (36,000 ft) altitude its… more…

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  Physics of flight

  When is the sound barrier broken?

  Mach 1 is reached when an aircraft matches the speed of sound, which isn't fixed: it depends only on air temperature. At sea level and 15°C it's about 1,225… more…

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  Physics of flight

  Why did the Vulcan 'howl' at air shows?

  Because of the layout of its air intakes. At around 90% power, the Vulcan's engines produced a distinctive howling noise caused by the shape of the intakes… more…

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  Physics of flight

  Why can't a Corsair pilot apply full power when going around after a failed carrier landing?

  Because at low speed and high power the Corsair would drop its left wing suddenly and with almost no warning, due to propeller torque. If the throttle was… more…

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  Physics of flight

  What is the speed of sound?

  The speed of sound isn't a moment in time but a measurable quantity: in air at 15 °C at sea level it equals 340 m/s, or 1,225 km/h (661 kn), and an aircraft… more…

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  Physics of flight

  Why do jet engines have a spiral?

  The spiral painted on a jet engine's spinner is a safety marking. When the fan is turning, the spiral blurs into a visible, pulsing pattern that warns ground… more…

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  Physics of flight

  Why do aircraft wings curve upward at the tips?

  Those bent tips are winglets (or sharklets, depending on the manufacturer), and they reduce the vortex that forms at the wingtip. By slowing the flow that… more…

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  Physics of flight

  How high do supersonic planes fly?

  Supersonic aircraft cruise far higher than airliners. Concorde flew at 15,000 to 18,300 m (50,000 to 60,000 ft) and the SR-71 operated above 24,000 m (80,000… more…

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  Physics of flight

  Where are an airplane's engines located?

  On most airliners, the engines hang under the wings in nacelles attached to pylons; on regional and business jets they sit on either side of the tail, and on… more…

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  Physics of flight

  What planes can go supersonic?

  Only aircraft designed for it: military fighters and interceptors (F-15, F-16, F-22, F-35, Rafale, Eurofighter Typhoon, Su-57), the B-1B bomber and a handful… more…

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  Physics of flight

  Why do planes zig zag?

  Airliners rarely fly perfectly straight because they follow published airways and waypoints, deviate around thunderstorms and turbulence, and are vectored by… more…

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  Physics of flight

  Why did early wartime fighter engines stall when flying upside down?

  Float carburetors use the venturi effect to feed fuel into the engine's intake, and they need a constant fuel level in the float bowl. Since the float works… more…

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  Physics of flight

  Why does the sound barrier break?

  The sound barrier is not a physical wall: it is the sharp rise in drag and loss of control that pilots met near the speed of sound (about 1,225 km/h, 661 kn… more…

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  Physics of flight

  Why do wings help birds fly?

  A bird's wing performs two jobs at once: its curved profile generates lift as it moves through the air, and its flapping also produces the thrust that drives… more…

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  Physics of flight

  What happens if an airplane's engines fail?

  If one engine fails, the aircraft keeps flying normally: every commercial airplane is certified to take off, climb and land with one engine out, and crews… more…

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  Physics of flight

  How did the P-38 make its two propellers spin in opposite directions?

  With "handed" engines: the two Allison V-1710s had crankshafts that turned in opposite directions, something relatively easy with that modular-design engine… more…

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  Physics of flight

  Why do birds' wings help them fly?

  Birds' wings generate lift the same way an airplane's do: their curved profile and the angle at which they cut through the air deflect the airflow downward… more…

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  Physics of flight

  What did the phrase "banking with intent to turn" mean among F-104 pilots?

  It was a joke among Canadian F-104 pilots: banking the aircraft "with intent to turn" referred to its poor low-speed turning. Its sustained turn capability… more…

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  Physics of flight

  How long does it take for a parrot's wings to grow?

  A parrot is not an aircraft, but the answer is specific: the chick is born with bare wings, and flight feathers grow in over weeks. A budgerigar flies 30-35… more…

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  Physics of flight

  At what altitude does a plane fly?

  A typical passenger aircraft cruises at about 11,000 m (36,000 ft), within a range of 9,000 to 12,500 m depending on the model, weight and flight distance. It… more…

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  Physics of flight

  How high could the F-104G climb in ballistic flight?

  In the late 1960s, pilots from 322 or 323 Squadron at Leeuwarden flew zoom climbs above 70,000 ft in the F-104G. On 8 November 1967 Captain Henk Krauss set a… more…

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  Physics of flight

  Why can't a plane land?

  A plane can't land when safety conditions aren't met: visibility below the procedure's minimums, crosswind or tailwind beyond the aircraft's limit, an… more…

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  Physics of flight

  How fast do hummingbirds flap their wings?

  A hummingbird flaps its wings between 50 and 80 times per second during normal flight; the ruby-throated hummingbird, the common species in eastern North… more…

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  Physics of flight

  At what speed does an airplane take off?

  A passenger jet takes off at around 250-300 km/h (135-160 kn): an A320 or 737 rotates at 260-280 km/h and a loaded 747 at 290-330 km/h. A light aircraft like… more…

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  Physics of flight

  Why do planes vibrate on takeoff?

  Most takeoff vibration comes from the runway, not the aircraft: tyres rolling over expansion joints and grooved pavement at 250 km/h (135 kn) shake the whole… more…

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  Physics of flight

  How does the sound barrier work?

  The sound barrier is the sharp rise in drag and control difficulty an aircraft meets as it nears Mach 1, about 1,062 km/h (573 kn) at cruise altitude. Air… more…

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  Physics of flight

  How much is the sound barrier?

  The sound barrier is not a price or a quantity: it is the speed of sound, which an aircraft meets at Mach 1. That speed is about 343 m/s (1,235 km/h, 667 kn)… more…

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  Physics of flight

  What is the A320's SHARP package for?

  SHARP (SHort AiRfield Package) improves takeoff and landing performance on short runways and is designed to increase low-speed lift. It combines aerodynamic… more…

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  Physics of flight

  What are contrails?

  Contrails are condensation trails: lines of ice crystals formed when the hot, humid exhaust of a jet engine mixes with air colder than −40 °C. Water vapour… more…

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  Physics of flight

  How high does the F-35 fly?

  The F-35 Lightning II has a service ceiling of about 15,240 m (50,000 ft), the figure published by Lockheed Martin and the USAF. On typical missions it… more…

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  Physics of flight

  Why do planes land sideways?

  An aircraft appears to land sideways in crosswinds: the pilot points the nose into the wind (the "crab" technique) so its ground track follows the runway… more…

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  Physics of flight

  What happens if you touch a butterfly's wings?

  Touching a butterfly's wings dislodges some of the microscopic scales that cover them — the fine powder left on your fingers. It isn't fatal and doesn't stop… more…

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  Physics of flight

  Why do planes vanish?

  Planes vanish from tracking when their transponder and ACARS stop transmitting, through failure, deliberate switch-off or loss of power, while beyond ground… more…

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  Physics of flight

  Why can an aircraft overcome the force of gravity?

  An aircraft doesn't overcome gravity: it balances it. Gravity still acts on it in full, but the wing generates an upward aerodynamic force of equal magnitude… more…

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  Physics of flight

  How far is the sound barrier?

  The sound barrier is not a distance but a speed: Mach 1, the local speed of sound, about 1,225 km/h (661 kn) at sea level and 1,062 km/h at 11 km. Airliners… more…

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  Physics of flight

  Why do planes use knots?

  Aviation uses knots because a knot is one nautical mile per hour, and a nautical mile equals one minute of latitude on a chart. That link between speed… more…

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  Physics of flight

  Why doesn't a plane fly in a straight line?

  Because the shortest route over a sphere isn't a straight line on the map but a great-circle arc, which on the standard projection appears curved toward the… more…

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  Physics of flight

  How long does it take for a plane to land?

  An airliner takes about 20-30 minutes from the start of its descent from cruise until touchdown, since the descent point lies some 150-200 km from the… more…

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  Physics of flight

  Is it normal for jet engines to flash flame sometimes?

  Yes, seeing a brief flash out of the nozzle is usually normal and doesn't indicate a fault. Turbofans emit flashes at startup, during abrupt power changes, or… more…

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  Physics of flight

  How much the speed of sound?

  In air at 20 °C the speed of sound is about 343 m/s, or 1,235 km/h (767 mph, 667 kn). It depends on temperature, not pressure: in the standard atmosphere it… more…

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  Physics of flight

  Why don't planes fly in a straight line?

  They do fly in a straight line, but on a sphere: the shortest route between two points is a great-circle arc, which on a flat map appears curved toward the… more…

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  Physics of flight

  Where do planes carry their fuel?

  Airliners carry almost all their fuel inside the wings, in integral tanks formed by the wing's own sealed structure, plus a center tank in the fuselage under… more…

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  Physics of flight

  What is airplane fuel called?

  The fuel used in jet and turboprop aircraft is aviation kerosene, sold as Jet A-1 in most of the world and Jet A in the United States. Light piston-engine… more…

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  Physics of flight

  How does the sound barrier break?

  The sound barrier is not broken so much as crossed: an aircraft with enough thrust and a shape that tolerates shock waves accelerates through Mach 1. Chuck… more…