Investigation Summary
The escape was meticulously planned by the Provisional IRA to free Seamus Twomey, J. B. O'Hagan, and Kevin Mallon. An individual using the alias Mr. Leonard hired a helicopter from Irish Helicopters at Dublin Airport, ostensibly for aerial photography in County Laois. On October 31, 1973, the pilot, Captain Thompson Boyes, was directed to a field in Stradbally where he was held at gunpoint by two masked men armed with a pistol and an Armalite rifle. One hijacker boarded the aircraft and forced Boyes to fly toward Dublin at low altitude, following railway lines and the Royal Canal to avoid radar detection and air traffic control contact. As they approached Mountjoy Prison, the pilot was ordered to land in the exercise yard where prisoners were walking in groups, some of whom were reportedly watching a football match. Prison officers initially failed to intervene, mistakenly believing the helicopter was carrying the Minister for Defence, Paddy Donegan. During the landing, other prisoners restrained the guards, allowing the three targets to board the five-seater Alouette II. The entire operation in the prison yard lasted less than one minute.
Final Conclusions
The escape was successful due to a combination of tactical surprise, the exploitation of civilian aviation infrastructure, and a lack of aerial security measures at Mountjoy Prison. The Irish government responded by launching a massive manhunt involving 20,000 personnel and transferring all IRA prisoners to the maximum-security Portlaoise Prison. Security at Mountjoy was subsequently upgraded with the installation of anti-helicopter wires over the exercise yards and the deployment of Irish Army personnel to the prison perimeter.
Video Analysis
IRA Mountjoy Helicopter Escape: Up and Away — A documentary detailing the 1973 helicopter escape from Mountjoy Prison, featuring accounts from witnesses and the pilot.
If playback is blocked, the owner has disabled embedding — use the link above.
Systems & Failure Modes
Aérospatiale Alouette II
A light, five-seater utility helicopter chosen for its agility and ability to land in the confined space of the prison yard.
Anti-Helicopter Wires
A security system consisting of steel cables strung across prison yards to prevent aircraft from landing or hovering low enough to extract prisoners.
Interesting Facts
- 01The escape was the first of its kind involving a helicopter in Ireland.
- 02The pilot, Captain Thompson Boyes, was released unharmed after the landing in Baldoyle.
- 03Seamus Twomey, the IRA Chief of Staff, remained at large until December 1977.
- 04Prison guards did not fire on the aircraft; they were initially confused, believing the helicopter carried the Minister for Defence, Paddy Donegan, and were subsequently restrained by other prisoners during the brief landing. While some later accounts suggest attempts to intervene, official reports emphasize the tactical surprise and lack of immediate armed response.
- 05The escape inspired the Wolfe Tones song 'The Helicopter Song', which reached number one on the Irish charts.
Safety Actions & Advisories
Prison Infrastructure Hardening
Installation of overhead wires across exercise yards at Mountjoy and other Irish prisons to prevent aerial access.
Military Perimeter Security
Deployment of the Irish Army to provide armed perimeter security at high-risk detention facilities.
Known Controversies & Unanswered Questions
Political Fallout and Security Negligence
Reference ↗The escape caused a major political crisis for the Fine Gael-led coalition government. Opposition party Fianna Fail criticized the government's 'law and order' platform, noting that the IRA's command structure had been able to orchestrate a complex escape from the state's primary prison. The confusion of the guards, who mistook the hijacked aircraft for a ministerial transport, was a point of significant public and parliamentary ridicule.
Location
ACCIDENT SITE · Coordinates taken from the wikipedia geotag.