This is the first question that I always ask in my Aviation Security class at the Metropolitan State University of Denver. Usually, about 2/3 of the class says “no.” I’m not sure how their answers are influenced by the media, or stories about TSA and buzz phrases like “security theater,” or what one of us so-called experts have said on TV, or the fact that many of them don’t remember a pre 9/11 travel experience, or what their parents tell them: but in terms of facts, its hard to argue that we’re not better off.
I truly believe that we are safer and I also believe that there are serious and significant gaps that continue to exist. Having been in aviation security before and after, I have a front line view of the industry and in this multi-blog series, I’m comparing aviation security before and after 9/11.
Part 1: Passenger & Carry-On Screening Technologies and Processes
Screening is the front door of aviation security. Screening is the most visible security layer and the most intimate as it can involve actually laying hands on people. Screening encompasses passengers, carry-on baggage, checked baggage and cargo. Also included is employee screening, but for now I’m going to focus on the first two: passengers and carry-on.
Passenger screening: prior to 9/11 the industry used walk-through metal detectors and some could have been as old as the early 1970s legislation that required their implementation. A metal detector does what it says on the box – detects metal. It does not detect explosives. At any point in time someone could have walked onto an aircraft carrying plastic explosives and the metal detector would have missed it entirely. Even if the detector alarmed, the barely effective pat down procedures likely wouldn’t have detected a surface to air missile concealed under passengers’ coat.
Today, the predominant form of passenger screening technology are body imaging devices, that can see right through clothing and detect the smallest of anomalies (including two packages of Stevia sweetener in my back pocket once). Known as Advanced Imaging Technologies (AIT) combined with software that protects the privacy of the individual, essentially creates an outline of a human form with red squares noting areas of interest. The pat-down procedure is about the dating equivalent of getting to 2nd base, so it’s controversial, but in terms of effectiveness compared to pre 9/11, it is far more effective.
Pre 9/11, the x-ray machines provided single angle look-down view and often the images were still in black and white. It was up to the screener to figure out what they were looking at. Screeners were tested by FAA agents, using weapons or inert explosives such as a hand grenade, encapsulated in such a hard plastic that it very nicely framed the test device when viewed in the scope, making it very easy to detect.. These test weapons were almost comical in their design and you’d need a pretty severe visual problem not to be able to see these things in an x-ray.
The x-ray machines never detected explosives – in fact they didn’t “detect” anything. They were just allowed an operator a fuzzy look inside a bag. Even after the bombing of Pan Am 103 in 1988, a Presidential commission concluded that existing x-ray technologies (i.e. x-rays) could not detect the plastic explosives in use at the time – yet we still did not change the x-ray machines.
Today, most x-ray machines are multiple-view, providing two angles, color, with gain and brightness adjustments and software that can make interpretations (if desired). Test weapons and explosives are run through Threat Image Projection (TIP) rather than live agent testing (which is still done – I’ll get to that in a minute). TIP projects an image of a threat item onto the screen and the screener (Transportation Security Officer) pushes an interrogate button. If the image disappears, it was a test. If it doesn’t it may be the real deal.
Transportation Security Specialist – Explosives (formerly referred to as bomb appraisal officers) often test TSO’s with unusual explosive designs and artfully concealed weapons to keep their skills honed and keep them from getting used to a specific type of test weapon. This rarely happened pre 9/11 and was conducted by FAA Special Agents; TSA did not exist pre 9/11 hence there were very few federal government explosives experts.
I’m saving the discussion of pre 9/11 contracted airline personnel vs post 9/11 TSA screeners for another post. While screeners can and do still miss some items (keeping in mind the prohibited items list is much larger than pre 9/11) the technology at the screening checkpoint in terms of passenger and carry-on bags, is clearly much more capable than post 9/11.by