The Transportation Security Administration trumpeted last week that it had screened a whole one million passengers through its brand new accelerated screening program, PreCheck. But although that seems like a high number, it’s really just the very tip of a large, slow-moving iceberg.

The L.A.Times notes that yes, one million passengers is a lot, but not so much when compared with the fact that the TSA screens a total of around 1.8 million passengers per day at the country’s 450 commercial airports.

So since the PreCheck program launched in October, the TSA has pushed about 335 million passengers through security. And only one million of those used the PreCheck program.

“In the context, 1 million is a very, very small number,” said Chris McLaughlin, assistant administrator for security operations at TSA. He added that the benefits of PreCheck to accelerate the overall system are still too small to calculate.

PreCheck is currently at 14 airports, and pre-approves passengers for American, Delta and Alaska that submit background info the TSA before heading to the airport. Those passengers are then allowed to go through a screening lane where they can leave on shoes, belts and coats, and save about half the time of normal passengers.

PreCheck lets travelers who volunteer background information to the TSA ahead of time go through special screening lanes without removing shoes, belts and coats. It cuts the estimated screening time as much as 50% for those who use it. As we’ve noted before, you still might end up going through standard screening, even if you’re signed up for PreCheck.

The program is set to expand by the end of 2012, and open in around 35 airports total. The airports involved serve around 90% of the nation’s travelers, says McLaughlin.

“By the end of this calendar year, we will be at a place where PreCheck will be contributing positively to the overall system,” he said.

TSA logs 1 million users of PreCheck program [The L.A. Times]

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