The Slovakian man who unwittingly carried RDX explosive on a flight from Slovakia to Ireland could have ended up being shot by a security guard, an aviation expert has said.

Gerry Byrne pointed to the incident on the London Tube where an innocent Brazilian man, Jean Charles de Menezes, was mistakenly shot dead by police who mistook him for a suicide bomber two weeks after the 7/7 atrocity in 2005.

"Why did not someone just tap him on the shoulder at the departure airport and tell him his luggage was carrying concealed explosives?" he asked on RTE's Morning Ireland.

"The failure to detect the explosives meant that some 10pc of flights out of Slovakia could have a bomb aboard and in the longer term the Irish authorities should occasionally check passengers arriving in Dublin from Slovakia.

"Checked in bags at Dublin Airport are tested for explosives by sniffer devices. The Israelis use detection equipment which can "sniff" minute quantities of explosives in the air," he said.

The incident drew comment on one major pilots' website today, with one saying: "Who needs terrorists... we have Slovakian security."

It was not the first time explosives have been mistakenly loaded onto a plane after security officials lost track of it. About 150 grams of explosive went missing at Paris' Charles de Gaulle airport when it was put into a passenger's bag during sniffer dog training in 2004.

The bag ended up on one of 90 flightsand airlines, airports and police forces around the world were alerted.

The RDX (Royal Demolition eXplosive) flown into Dublin is one of the most commonly used explosives in the world.

Invented in Germany in 1899, it was widely used by all sides in World War Two and 6,600 lbs of it were used in the bombs dropped by the RAF during the famous "Dambusters" raid.

It can be used as a component of Semtex-H and is used in the US military. In civilian use, it has been used for demolishing buildings, as a heating fuel and even as a rodent killer.