The Defence Minister said staff cutbacks are not to blame for the Air Corps not being able to provide services outside of normal working hours.
It emerged the Defence Forces were initially asked to provide 'top cover' off the west coast that resulted in Coastguard Rescue 116 being deployed when it crashed.
A shortage of qualified pilots and other crew means the Air Corps cannot provide the fixed-wing CASA aircraft from 6pm to 8am.
Minister Paul Kehoe told the Dáil that along with retirements, people are being attracted to the private sector.
“I will be the first to put my hands up and say there is a shortage of personnel. The reason why is there are attractive positions outside the Air Corps.
"There are a number of issues happening in the background to see can we address other issues about retaining specific people who have a specific set of skills .”