The five anti-war protesters accused of criminally damaging a US navy aircraft will say they acted in defence of others, a Dublin Circuit Criminal Court jury has heard.
Implements used to damage the aircraft were engraved with Celtic symbols and slogans.
Opening the case, Conor Devally SC, prosecuting, said that there was "no huge issue" on the facts of the case but rather whether the five felt they had "lawful excuse".
Damien Moran and Ciarán O'Reilly, South Circular Road, Rialto, Dublin; Nuin Dunlop from the US, Walkinstown, Dublin; Karen Fallon from Scotland, South Circular Road, and Deirdre Clancy, Clontarf, Dublin, have pleaded not guilty to two counts each of causing damage without lawful excuse to a naval aircraft, property of the US government, and to door panels, property of Aer Rianta, at Shannon airport in February 2003.
The jury heard that a C40 or 737 aircraft, which could convey cargo and personnel, had arrived at Shannon from Texas.
Sgt Michael O'Connell said he was on security duty at a maintenance hangar in Shannon which housed the aircraft. At about 3.45am he heard glass break and then saw five people, one with a large axe and the others with hammers, enter the hangar.
He ran towards them and shouted "stop". Sgt O'Connell said he held his arms out but they ran around him. He "pleaded with them to stop" and called Shannon Garda for urgent assistance.
Sgt O'Connell said he was "terrorised by their appearance" and heard them say words which might have included "God".
Mr O'Reilly was "belting an axe into the front nose cone of the plane" as Mr Moran hit the side engine cover with a hammer, he said. The three women were at the back hitting the exhaust pipe and an image of the Texas flag with three lump hammers as well as an inflatable Tricolour hammer.
Sgt O'Connell said he struggled with both men and managed to take their weapons from them. They offered no further resistance. The women handed over their hammers and all five knelt in a circle to recite the rosary.
Sgt O'Connell agreed with Michael O'Higgins SC, defending Ms Dunlop and Ms Clancy, that they were "polite and co-operative" and showed no malice. "They came in to disarm the aircraft," said Mr O'Higgins, to which Sgt O'Connell replied: "I say they came in to cause criminal damage."
Items including copies of the Bible and Koran, rosary beads, Muslim prayer beads and photographs purporting to depict the effects on children of the previous war in Iraq were found forming a "shrine" at the side of the aircraft.
Cmdr James Nichols, who arrived in Ireland on the aircraft before the damage was done, agreed with Roderick O'Hanlon SC, defending Mr Moran and Mr O'Reilly, that it was unable to fly safely following the incident.
Cmdr Nichols said he was unaware of the aircraft's mission following its stop in Shannon but then agreed that he was aware from an earlier trial that its original mission was to fly to Sigonella, a US military base on Sicily.
Det Garda John Duffy of Ennis Garda station told Brendan Nix SC, defending Ms Fallon, that to the best of his knowledge, no US military aircraft were checked at Shannon "by the police or Army of the Republic of Ireland".
The hearing continues before Judge Donagh McDonagh and a jury.