TORONTO -- Two brazen jailbreaks from Quebec correctional facilities involving the use of helicopters may have shocked everyday Canadians, but security experts say such daring escapes have been dictating Canadian prison designs for years.

Modern day prisons have safeguards built into both their architectural and technological infrastructures, while even older facilities have begun taking steps to prevent the sort of bold manoeuvres that have seen five inmates fly to freedom over the past 15 months.

The most recent escape took place on Saturday when a helicopter touched down in the courtyard of the Orsainville Detention Centre near Quebec City, then promptly took off again with three murder suspects on board. As of Sunday night, the three men were still at large.

In March 2013, a similar scene unfolded at a facility in St-Jerome, Que. about 60 kilometres from Montreal.

Two men allegedly held a helicopter pilot at gunpoint and forced him to fly over the prison courtyard, from which two inmates scaled a rope ladder and clambered on board. Their bid for freedom was short-lived, as they and their alleged co-conspirators were arrested within hours.

Experts say open-air courtyards have long represented a security weakness for correctional facilities, adding modern practices have actively worked to close the loophole.

Colin Lobo, whose company Lobo Consulting Services offers security advice to Canada's prisons and courthouses, says designers have dropped the concept of an outdoor courtyard entirely, adding the possibility of dramatic prison breaks directly influenced the decision.

"For newer facilities, what ends up happening is they don't have these types of courtyards anymore. Everything is actually fully enclosed, an it actually prevents such things from occurring," Lobo said in a telephone interview. "The inmates can't escape at all."

Even less modern jails have begun taking steps to prevent flights by installing mesh over their courtyards, Lobo said. This precaution not only has the capacity to thwart airborne escapes, but has the added bonus of limiting the amount of contraband that can be dropped into the facility, he added.

Lobo said such measures are standard practice at federally designated medium and maximum-security institutions. Minimum-security operations would not house high-risk inmates, he added.

While provincial facilities are not classified in the same way, Lobo said many of them have begun adopting the more stringent security standards as well.

This includes complementing architectural innovations with more sophisticated surveillance technology, Lobo said.

"There's video analytics . . . that alert security personnel of an incident or a potential incident," he said. "They can start telling security personnel that there's people in the area that shouldn't be, or that they're moving in a direction that they shouldn't be moving into."

Kevin Grabowsky, national president of the Union of Canadian Correctional Officers, said federal facilities have other weapons in their arsenal - literal ones.

Federal prison guards are authorized to carry guns and to fire them at inmates trying to flee, he said, adding provincial staff are not allowed to bear arms.

He said policies have been specifically written to deal with helicopter escapes, and staff have clear instructions as to what they can and cannot target.

"Our directives are not to shoot at the helicopter, per se, but you can certainly shoot at the people trying to get on it," he said.

Lobo concedes that older jails are much easier targets for the sort of daring breakouts seen in Quebec.

He said many of them have been classified as heritage sites, making the cost of performing upgrades unsustainable in some cases.

"It does cost a lot of money to fully renovate a facility, but there are smaller measures taken here and there to work with existing conditions to try to improve it the best we can."