OTTAWA - National Defence is examining whether to equip the air force's Cormorant search-and-rescue helicopters with hand-held infrared sensors to detect crash victims and those lost in the wilderness, The Canadian Press has learned.

Critics say the lack of heat-detecting sensors might have delayed the rescue of two Swedes from an Arctic ice floe earlier this month.

The air force confirmed Friday that neither the CH-149 Cormorant nor the C-130 Hercules assigned to search missions are equipped with infrared sensors which, among other things, detect body heat and provide high-resolution video at great distances and heights.

The imaging package is standard among many agencies that conduct rescue missions, including the RCMP, some provincial governments and volunteer organizations.

Such a system was also recently installed on the air force's CH-146 Griffon utility helicopters bound for Afghanistan.

The air force did not make it a mandatory requirement to install in the Cormorants when the 15 helicopters were purchased five years ago, said Lt.-Col. John Blakely, a spokesman for the chief of air staff.

"The air force is examining the potential acquisition of hand-held thermal imaging sensors to further enhance search capabilities," he said.

Pilots already wear night-vision goggles during missions after dark, Blakely noted.

The hand-held scopes the air force is considering would be a step down from more advanced systems that can be built into the aircraft.

Blakely wouldn't rule out acquiring the higher grade infrared systems in the future but did not explain why they are not currently being considered.

The idea of using a hand-held system came after a military flight crew borrowed a thermal-imaging scope from civilians to help in the search for a missing child near Comox, B.C.

Their experience prompted what's known in the military as a capability deficiency statement, where defence planners are formally alerted to an important piece equipment that units don't have but should acquire.

The absence of thermal devices was brought sharply into focus with the crash of a twin-engine Cessna Skymaster south of Baffin Island on Dec. 7, where two men from Sweden survived 18 hours on a frigid, wind-swept ice pan.

One of the pilots, Oliver Edwards-Neil, said he and his partner heard search aircraft nearby during the first day of their ordeal and their hearts sank as the engine sounds faded into the distance.

The air force would not say whether the absence of thermal-imaging equipment prevented flight crews from rescuing the stranded men sooner.

"To comment on this would be highly speculative," said Blakely.

The old Labrador helicopters, which the Cormorants replaced, were not equipped with any heat-detecting system and defence planners challenged the air force in the late 1990s, questioning whether it was necessary.

The head of the country's leading civilian search organization said he was surprised when told the military helicopters did not have the high-tech system.

Harry Blackmore was riding in the back of a Cormorant, skimming the treetops in his native Newfoundland, when he noticed there were no infrared imaging screens.

"I honestly didn't know," Blackmore, president of the Search and Rescue Volunteer Association of Canada.

"I honestly thought they had them and having them is definitely a matter of life and death, especially at this time of year."

A research paper, written at the Canadian Forces Command College in 2004, warned that the country has "lagged behind considerably in updating" its search-and-rescue system to take advantage of new sensor technology.