An Cosantóir

12 | To maintain a serviceable fleet of aircraft for the duration of the visit the FTS technical staff worked tirelessly to not only service, but to arm and disarm the aircraft on a near continuous basis. To their credit, this resulted in a 100% dispatch rate for the entire visit, ensuring a continuous patrolling presence. For CAS and DCA patrolling the PC-9M is armed with .5" heavy machine-guns, and pilots are trained to respond to a wide range of complex scenarios. Everything that happens in the air is controlled from the ground, which means that FTS pilots do not act without the authority of the air defence commander, who maintains a position near the radar-guided intercept controllers (RGIC) that the air traffic controllers in Baldonnel are specifically trained for. "If an aircraft is located in the vicinity we will get a call to tell us an aircraft is approaching the EZ either on a 'high aspect' or a 'low aspect'," said Capt O'Riordan, "High aspect means that the target aircraft is looking likely to enter the EZ, while a low aspect means that, given its current trajectory, it will not pose any threat to the EZ. "If it is high aspect and the RGI controller deems an intercept is likely or necessary, our first task is to intercept the aircraft and identify it. As the PC-9M is not radar equipped, we must work out mathematically what the best intercept vector will be. Once a successful interception has been completed, we pass the relevant information to the RGIC who in turn passes it onto the air defence commander. The ADC will then make the next decision in conjunction with higher authorities as to what subsequent actions the aircrew will take. On 99% of occasions the likelihood is that the aircraft that has been intercepted An Cosantóir Dec 2012/Jan 2013 www.dfmagazine.ie does not want to be there in the first place. They may be on the wrong communications frequency or simply in the wrong place at the wrong time." During the queen's visit the flight path of a helicopter travelling from Northern Ireland to the K-Club in Kildare would have taken it very close to the queen's flight path as she was arriving into Baldonnel. A PC-9M on a CAP patrol to the north of Dublin Airport was ordered to carry out an interception. Once communication with the helicopter had been re-established with ATC, it was escorted away from the EZ. "On intercepting an aircraft you relay all information," Capt O'Riordan said, "aircraft type, registration, passengers, if any, and the condition of crew or their actions. They may give you a signal indicating they are fine but their radio equipment is not working or they may be simply alerted to the fact that they have inadvertently strayed into prohibited airspace." The PC-9M pilots will either be given the order to escort or shepherd the aircraft out of the EZ. "To escort means to fly behind the intercepted aircraft and verify that they leave the EZ," Capt O'Riordan explained, "whereas to 'shepherd' an aircraft means you physically have to ensure that the aircraft leaves the EZ. In that case the PC-9M pilot will manoeuvre his aircraft to come up alongside the intercepted aircraft which ensures he can be seen by the crew. The pilot then rocks his aircraft's wings, which is the recognised international signal to let them know that they need to follow - of course, if communications have

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