There is a certain "je ne sais quoi" about airplanes for terrorists, an aviation expert has said.
Philip Baum, editor of Aviation Security International, said there are a number of reasons why terrorists target airports and airplanes specifically.
Speaking ahead of the 13th anniversary of the 9/11 attacks on the Twin Towers in New York, in which 2,977 victims were killed and thousands more injured, Baum described aviation as the "ultimate target" for terrorists.
He told IBTimes UK: "There is a certain je ne se quoi, a certain appeal about aviation. It's the ultimate target. You're pretty much guaranteed worldwide coverage, you're guaranteed media coverage.
"You're playing on people's natural fears of flying and you've got a large number of nationalities in a small aluminium tube. If you hit the 33 bus in Hammersmith, chances are 95% or higher will be Londoners."
However, Baum also warned that the risks involved in flying are very small, and that people focus too much on the terrorism threat to aviation.
Earlier this week, Luton Airport was evacuated and flights were diverted after a suspicious package was found. After bomb disposal units carried out a controlled explosion, it emerged the item was a pair of hair straighteners.
"I think people should be on high alert, but I don't think it should relate specifically to aviation," he said. "If anything I think we are too complacent in other areas of our lives. What security checks are you realistically doing if you go to the theatre in the West End? What security checks are there on the London Underground?
"Flying is extremely safe, especially when you compare it to other modes of transport. But the reality is every time there is an aviation disaster the media makes a big thing out of it. We don't really make anything out of car crashes."