Concorde was restricted to only go supersonic over the ocean because it sent a shockwave into the air strong enough to shatter glass if it went over densely populated areas. Cities issued numerous noise complaints whenever Concorde flew overhead, causing huge headaches for the airlines and manufacturers.

Yes, the Concorde could and did break windows during its operational life, which is why it was eventually banned from flying at supersonic speeds over land. When an aircraft breaks the sound barrier, it creates a "sonic boom"—a continuous wave of compressed air that follows the plane. On the ground, this sounds like a massive explosion or a double-thunderclap. At the Concorde's cruising altitude of 60,000 feet, the pressure wave was often strong enough to shatter glass, crack plaster, and set off car alarms. In the early days of testing, the "overpressure" from the boom caused significant structural damage to greenhouses and old buildings in the UK and France. This led to "supersonic corridors" being established exclusively over the Atlantic and other oceans. In 2026, new "quiet supersonic" technology, like NASA’s X-59, is being tested to see if the boom can be reduced to a "thump," potentially allowing supersonic flight over land for the first time in decades.