TSA sped up lines by screening known travelers less

Since its post-9/11 founding, TSA had screened every passenger with the same intensive process regardless of any information already known about them, on the premise that treating everyone identically was the only fair and secure approach. As passenger volume grew year over year, that uniform screening produced longer lines and more resource strain without any added security value from screening low-risk travelers as intensively as unknown ones.

Rather than ask for more checkpoint lanes, staff, or faster scanners, TSA piloted a risk-based approach starting in 2011: travelers who volunteered background information and passed a vetting check could be pre-classified as low-risk and given an expedited lane, freeing standard-lane resources to concentrate more fully on travelers TSA knew nothing about — solving the throughput problem by changing who needed full screening, not by screening faster.

Split the checkpoint by what was already known: vetted travelers get a cheap fast lane, freeing full screening for the unvetted where security value lies.

Pre-vetting travelers lets TSA route them through a lighter process, reducing demand on the standard lane.

Standard lane resources concentrate on unvetted travelers, where intensive screening adds security value.

Changing who needs full screening avoids proportional increases in staff or equipment.

Aggregate wait times drop because the fast lane handles many travelers cheaply.

When a uniform process is slow, don't just add capacity—separate low-risk cases from unknown ones and focus the expensive process on the latter.

A Cincinnati study found PreCheck's median wait was 2.4 minutes versus 8.9 for standard lanes; enrollment passed 20 million by 2024. PreCheck became the standard model for risk-based aviation security worldwide, expanded through partnerships like Global Entry and CLEAR, and is credited with letting US checkpoint throughput keep pace with rising air travel without proportional increases in screening staff.