Even though TSA has put these so-called Advanced Imaging Technology (AIT) scanners through both laboratory and operational testing, Congress's own auditing agency says it "remains unclear" that they can actually do the primary job they are intended to do.
Steve Lord, the GAO's director of homeland security and justice issues, made this point most recently in written testimony presented last Thursday to the Senate Commerce Subcommittee on Aviation Operations, Safety and Security.
"Furthermore, as noted in our March 2010 testimony," Lord wrote, "it remains unclear whether the AIT would have been able to detect the weapon used in the December 2009 incident based on the preliminary TSA information we have received."
TSA initially intended to deploy far fewer AIT whole-body-image scanners. But it changed its mind specifically in response to Abdulmutallab's attempted Christmas underwear bombing.
"In response to the December 25, 2009, attempted attack on Northwest Flight 253, TSA revised the AIT procurement and deployment strategy, increasing the planned deployment of AITs from 878 to 1,800 units and using AITs as a primary -- instead of a secondary -- screening measure where feasible," GAO's Lord told the House Homeland Security Subcommittee on Transportation Security on March 17.
Lord told that subcommittee that "operational testing for the AIT was successfully completed late in 2009 before its deployment was fully initiated." However, Lord said, "While officials said AITs performed as well as physical pat-downs in operational tests, it remains unclear whether the AIT would have detected the weapon used in the December 2009 incident based on the preliminary information GAO has received."
Three months later, in a letter to Republican Rep. John Mica of Florida, the ranking member of the House Transportation Committee, the GAO restated its assessment that the government did not know if the scanners would detect underwear bombs.
"While officials said AITs performed as well as physical pat-downs in operational tests, it remains unclear whether the AIT would have detected the weapon used in the December 2009 incident based on the preliminary information we have received," said the letter.
I asked TSA if it contested GAO testimony that "it 'remains unclear" to the U.S. government that the 1,800 ATI whole body image scanners that TSA is in the process of deploying at airports around the country will in fact detect the sort of underwear bomb used in the attempted attack on Northwest Flight 253 on December 25, 2009."
TSA spokesperson Sterling Payne responded by email. "While there is no silver bullet technology, advanced imaging technology is very effective at detecting metallic and nonmetallic threats on passengers, including explosives," said Payne. "Further, this technology doesn't stand alone: It's one part of our multi-layered strategy to minimize risk, deter future attacks and protect the traveling public.
"TSA began piloting imaging technology in early 2007," said Payne. "Through the pilot process, TSA gained operational information used to enhance training, improve the screening process and further bolster detection capabilities. Using this critical technology, TSA routinely detects artfully concealed metallic and nonmetallic prohibited items. TSA completed comprehensive operational testing and evaluation of this technology and is confident that it will significantly increase our detection capability at the checkpoint."
Payne said the AIT scanners cost between $130,000 and $170,000 per unit. That means deploying the full 1,800 will cost taxpayers between $2.34 billion and $3.06 billion.
And even if they could be counted on to detect an underwear bomb, the TSA, after buying 1,800 of them, intends to leave 500 domestic airport security checkpoints without them.
"There's about, from my understanding, 2,300 checkpoints," Lord told the Senate subcommittee last week. "So if you acquire 1,800 machines, it's still not going to be enough to ensure 100 percent coverage. TSA's strategy is to focus the use of these machines on the highest-volume airports."
Whether in fact a whole-body-image scanner catches a future underwear bomber boarding a flight in a foreign airport will depend not only on the effectiveness of the scanner, but on the country in which the airport is located. "At least 13 other nations are now testing or deploying these scanners, or have committed to deploying them in the near future," Lord told the Senate subcommittee.