The airline industry has grown by up to 7% in the last decade. The official airlines of most countries have recorded more than 1.5 billion travelers last year, due to the strength of tourism and business.
But the last few years have been difficult for the aviation industry. The attacks on the World Trade Center on September 11 and the resulting delays in airport security dealt a heavy blow to the aviation industry. Geoff Freeman, executive vice president of the US Travel Association, said, “The post-9/11 environment is making it extremely difficult for the TSA (Transportation Security Administration) to facilitate travel security.”
Although airport security has always been tight, the 9/11 attacks woke people up to the harsh reality that it wasn’t tight enough.
New technology used for security:
Two new forms of technologies that are now used for security checks at airports. The DHS (Department of Home Security) has been rolling out backscatter Advanced Imaging Technology (AIT) units, each costing between $130,000 and $170,000. “Backscatter technology projects a beam of ionizing X-rays onto the body’s surface to produce an image that resembles a chalk etching.”
Backscatter technology requires a passenger to stand between two box panels; low-dose radiation is delivered from the panels to the body, primarily to the scalp during the scan. This image is then sent to an assigned agent in another room protecting the passenger’s privacy to ensure the anonymity of the image. If the agent finds a threat, he can call another agent to inspect the image further.
The other technology, the active millimeter wave scanner, is a whole body imaging device, the competing technology is backscattered X-ray wave systems, they can penetrate clothing to expose hidden threats, but do not emit radiation harmful.
How airport security works:
Considering all the issues related to time consumption, passenger health and privacy, and most importantly airway safety, high-tech solutions can be divided into several parts and used to guarantee the safety of flights and we can also consider that what we are doing is enough.
The first line of defense:
At first we have to understand the psychology of a terrorist. For a second, imagine that you are a terrorist who wants to hijack a plane and blow it up. You are well aware that when you enter the airport, you must go through metal detectors, bomb-sniffing dogs, and possibly a search of your luggage and clothing. How could one circumvent those security measures? He/she could climb a fence; otherwise drive a truck to a safe area of the airport.
That is why the first line of defense at an airport is the most obvious topic and includes fences, walls, and barriers. Tall fences that would be difficult to climb can be used to enclose all airport property. Security patrols regularly scan the perimeter if anyone tries to break through the fence. Especially in sensitive areas such as fuel depots, terminals and baggage handling facilities, fencing and security checkpoints are a must. All access doors must be monitored by surveillance cameras or a guard station.
Now consider the risk, if someone could drive a car or truck with a bomb into the airport terminal entrance and blow up the airport itself! Large truck-sized concrete barriers can be deployed, if any threats are detected. Cargo zones, where people park their cars and put luggage in or out of the trunk, are now kept clear of traffic. No one can park their cars near the terminal.
Your identity please:
One of the most important security measures is confirmation of the traveler’s identity and is done by checking photo identification such as a driver’s license or national ID card. To travel internationally, your passport is essential.
Just taking a look at a photo ID is not enough today. High-tech biometrics are now used to verify fingerprints, retinal scans, and facial patterns using complex computer systems to ensure that someone is who they say they are, or matches a list of potential terrorists determined by the government.
A new system called CAPPS II (Computer Assisted Passenger Screening System) could help airport security that requires more personal information from travelers, leading to a risk assessment as no risk, high risk, unknown risk, or high risk. Travelers deemed at risk will be re-screened.
An airport public address system continually plays an automated message telling you not to leave your luggage unattended and asking you some strange-sounding questions:
• Has your luggage always been in your possession?
• Has anyone given you anything or asked you to carry or check an item for them?
These are the most important questions they ask. One tactic that terrorists can use is to hide a bomb inside the luggage of an unsuspecting person. Another tactic is to give something, such as a toy, to someone who is about to board a plane. That innocent looking object could be a bomb or any other harmful device.
Metal detector: pass, please:
All public entrances to an airport are equipped with metal detectors, where everyone must go through and luggage must go through an X-ray machine. Those metal detectors are usually based on pulse induction (PI). If a metal object passes through it, the pulse creates an opposing magnetic field in the object and consequently produces an “echo” showing that the passenger has something metal.
Many newer metal detectors are multi-zone, which means they have multiple transmitters and receivers, each at a different height. Basically, it’s like a unit that has multiple detectors.
X-ray system: advance please:
As you go through the metal detector, your carry-on baggage goes through the X-ray system. The machine used at airports is typically based on a dual-energy X-ray system.
Since different materials absorb X-rays at different levels, the image on the monitor is colored, depending on the range of energy passing through the object, and represents one of three main categories:
• Organic
• Inorganic
• Metal
All X-ray systems use shades of orange to represent “organic.” This is because most explosives are organic. Since machine operators are well trained, they can search for suspicious items such as Improvised Explosive Devices (IEDs). An IED can be made in a bewildering variety of ways, from basic pipeline bombs to sophisticated, electronically controlled component bombs.
Electronic items, like a laptop, have many different items packed into a small area. Therefore, it can be difficult to determine if a bomb is hidden within the device. That is why airports also have a chemical tracer. The security assistant quickly slides a cloth over the detected device and places the cloth over the detector. The tracker scans the fabric for any traces of chemicals used to make bombs and can alert the security assistant to a possible bomb.
Now, let’s see what’s happening with checked baggage.
X-ray systems: check your bags
In addition to passenger baggage, planes also carry large amounts of cargo. All this cargo has to be checked before being loaded.
Airports mainly use one of three systems to do this:
• Medium X-ray Systems – These stationary systems are used to scan an entire pallet of cargo for suspicious items.
• Mobile X-ray Systems – By using this system, a large loaded truck can be scanned. All truck contents are scanned for suspicious items.
• Fixed Site Systems – This is an entire building that is basically one huge X-ray scanner. A truck trailer is driven into that building and the entire loaded truck is scanned at once.
An outdated bomb detection technique – the use of trained dogs still works and sometimes works better than most high-tech systems. These special dogs, called K-9 units, are well trained to sniff out the exact scents given off by the chemicals used to make bombs and the scents of other items, such as drugs. A K-9 barks at a suspicious bag or package, warning the human partner that this item needs to be investigated.
In addition to an X-ray system, many airports also use larger scanners. Let’s take a look at the following.
CT scanners: check your bags
In the United States, most major airports have a computed tomography (CT) scanner. She circles her bag, the X-ray mechanism slowly spinning around her, bombarding it with X-rays and recording the resulting data. This scanner uses this data to make a very detailed tomogram (slice) of the baggage. The scanner can perform the calculation of the mass and density of the individual objects in the bag based on this tomogram. If the mass/density of an object falls within the range of a hazardous material, the CT scanner alerts the operator of a potentially hazardous object.
The CT scanner is slow compared to other types of baggage scanning systems. Because of this, most other countries, particularly in Europe, use a larger version of the X-ray system for checking carry-on items. It has a higher KVP range and high X-ray speed and automated machines integrated into the normal baggage handling system.
With all these detectors, scanners, and trackers, it’s pretty obvious that no one can carry a weapon or bomb on a plane.
