The recent bombing of an aircraft operated by Daallo Airlines, on a flight departing from Mogadishu, apparently utilised an Improvised Explosive Device (IED) concealed within a laptop computer. Whether or not the attack was the result of a failure to effectively screen carry-on baggage, or exploitation of the opportunities afforded the ‘insider’, the case highlights the fact that screening laptops, tablets and other electronic items can be very challenging and, unless one knows what to look for, a poorly trained X-ray operator can easily miss artfully concealed explosives and the associated components of an IED. John Howell shares his expertise.
Laptops can be converted into IEDs, but the amount of space within them is limited, so therefore minimises the quantity of explosives which can be contained therein. There are two methods that can be employed to manufacture a laptop IED. The first would be removing internal components to make room for the explosives and firing circuit. The second, and more challenging, would be using the very limited open space inside the laptop and pack in the explosives. So, when screening laptops at a checkpoint, the first thing one needs to know is what a normal laptop looks like under X-ray examination. Once one knows this, the screener is better equipped to find a laptop that has been altered or converted into an IED.
The image below shows the basic internal components of a typical laptop and what one would expect to see in an X-ray image. The two main colours visible are GREEN and BLUE; there should not be any large areas of dark ORANGE, indicating the presence of organic material. It is normal to see very light shades of orange in the X-ray image, as this reflects the material of the outer casing of the laptop. Laptops themselves, however, do not contain organic material, so anytime dark orange appears in an image of any type of electronic appliance, something is not right.
When screening a laptop, it should be X-rayed by itself, outside of the person’s carry-on baggage. This is because all of the other items in the bag may combine in the X-ray image, making it next to impossible to see the explosives or the IED circuit components (battery, switch, detonator, etc.). The presence of an organic item in a bag, like a bottle of water or apple, will appear in dark orange as if it were inside the laptop.
95% of explosives appear orange in an X-ray image, but we should remember that there are some, such as black powder and chlorates, which do appear green.
So when looking at the above image, one can see that it is very hard to figure out what is the laptop and what is not. All of the other items in the bag blend right into the laptop making it almost impossible to tell what is going on. By removing the laptop from the bag and X-raying it separately, one can better determine what is in the bag and whether or not the laptop has been altered.
Let’s look at some laptops that have been altered and turned into IED’s, starting with an easy image of a laptop that has had most of the internal components removed to make room for the explosives and IED circuit components. The below image is of a laptop that has about 1 lb of homemade explosives (HMTD) packed into the unit. Can you see the explosives, cardboard improvised blasting cap and digital timer?
Because the ‘terrorist’ took out so many internal parts of the laptop, we can see the explosives, displayed in orange, and the digital timer which is located in the lower left side. A properly trained security screener should be able to identify that this laptop has been turned into an IED.
The next laptop is much more complex and has about 1 lb of sheet explosive packed in the open space behind the screen; none of the internal components have been removed. The ‘terrorist’ also used the laptop’s internal power instead of adding another power source to fire the blasting cap. This laptop is designed to be activated by the person carrying it – the type of device a suicide bomber might utilise.
This is not as easy to pick out as the previous example. Only by looking very closely can one see an orange square in the centre of the laptop. It is very feint, making the odds of detecting this at a real checkpoint very low. Also, one cannot see the detonator. This was a very eye-opening image when we first developed this training aid as we could see, and demonstrate, that typical screening procedures for laptops are not sufficient for the detection of an IED of this nature.
So clearly, if the terrorist does not remove internal components in the laptop, it becomes much more difficult to identify this laptop as an IED. In which case, how are security screeners going to find this at a checkpoint and prevent it from boarding an aircraft? The only way to improve the chances of detecting this with an X-ray machine is by having the passenger (or staff member) open the lid of the laptop prior to placing it on the X-ray conveyor for inspection. Take a look at the below image of the same laptop, but now with the lid open and compare it with the previous image where the lid was closed.