Taking a commercial flight from a US airport generally requires a boarding pass to get near a gate, security screening controlled by the federal government and careful attention to carry-on bags.
It wasn’t always this way.
The security system travelers encounter today was built layer by layer, often after attacks or attempted attacks exposed new vulnerabilities — from bombs hidden in luggage to hijackers who turned airplanes into weapons.
No single day changed air travel more dramatically than September 11, 2001.
Before then, authorities presumed aircraft hijackers would seek to negotiate, not deliberately crash a plane as part of an attack.
The Federal Aviation Administration immediately restricted airport gate access to ticketed passengers and banned knives and box cutters from carry-on bags. Congress created the Transportation Security Administration, shifting responsibility for screening passengers, baggage and other cargo to a federal workforce. The same law required reinforced cockpit doors, more federal air marshals and 100% screening of checked luggage for explosives.
The range of security flaws that 9/11 exposed came after authorities and the industry had spent more than a decade addressing gaps revealed by earlier attacks.
{{/usCountry}}The range of security flaws that 9/11 exposed came after authorities and the industry had spent more than a decade addressing gaps revealed by earlier attacks.
{{/usCountry}}Almost 13 years before 9/11, a bomb destroyed a jumbo jet operated by a US airline as it flew at 31,000 feet over Lockerbie, Scotland, killing all 259 people aboard and 11 on the ground. Investigators determined an explosive device hidden in a radio-cassette player had been inside a suitcase checked in Malta and ultimately transferred to Pan Am Flight 103 without an accompanying passenger.
The December 21, 1988, attack on the London-to-New York flight “stimulated the most significant changes in aviation security since the early 1970s,” former FAA Administrator Jane Garvey told the 9/11 Commission in 2003.
The FAA ordered US carriers at airports in Europe and the Middle East to X-ray or physically search all checked baggage.
The FAA also assigned security personnel at major US and foreign airports, established intelligence-sharing agreements, tightened cargo controls and developed explosives-detection technology.
Three months and 11 days after 9/11, Richard Reid boarded American Airlines Flight 63 from Paris to Miami with explosives hidden in his shoes. He tried to ignite them midflight but was subdued by passengers and crew. After the Dec. 22, 2001, incident, TSA and airlines asked passengers to remove their shoes voluntarily during security screening. Shoe removal became mandatory less than five years later, when TSA also restricted outside liquids and gels.
The changes followed a British announcement that authorities had disrupted a plot to use liquid explosives concealed in beverage bottles to destroy seven transatlantic airliners. TSA immediately banned nearly all liquids, gels and aerosols beyond security screening, later replacing the prohibition with the “3-1-1” rule limiting passengers to containers of 3.4 ounces or less that must fit in a single quart-sized, clear plastic bag.
On Christmas Day 2009, a passenger on Northwest Airlines Flight 253 tried to detonate explosives hidden in his underwear as the plane approached Detroit. The device failed but caused a fire, and Umar Farouk Abdulmutallab was severely burned. He pleaded guilty to attempting to destroy the aircraft. Traditional metal detectors could not detect the plastic explosives under Abdulmutallab’s clothes. TSA was already testing full-body scanners, and the incident persuaded authorities to fast-track the technology.
Security screening continues to evolve. TSA has been expanding facial recognition technology to verify passengers’ identities. As of last month, newly manufactured passenger airplanes must have a retractable security gate between the cabin and flight deck to protect the cockpit when its reinforced main door is open. The Air Line Pilots Association wants the secondary barriers added to existing aircraft.