how 9 11 changed air travel?

how 9 11 changed air travel?
In November 2001, the Transportation Security Administration (TSA) was introduced to take over all of the security functions of the FAA, the airlines, and the airports. Among other changes introduced by TSA, bulletproof and locked cockpit doors became standard on commercial passenger aircraft.
Full answer in: en.wikipedia.org
More questions like: how 9 11 changed air travel?
What changed in aviation after September 11th?
Shortly after the 9/11 terrorist attacks, Congress passed the Aviation and Transportation Security Act (PDF), which created the Transportation Security Administration (TSA) and mandated that federal employees be in charge of airport security screening.
Full answer in: www.cfr.org
When did Flights resume after 911?
Civilian air traffic was allowed to resume on September 13, 2001, with stricter airport security checks, disallowing for example the box cutting knives that were used by the hijackers. (Reinforcement of cockpit doors began in October 2001, and was required for larger airlines by 2003.)
Full answer in: en.wikipedia.org