Canada's famed Snowbirds aerobatic team has been grounded just as air show season gets underway because of a technical problem with the aircraft's ejection seat system, raising yet more questions about the safety of the aging fleet.

The air force has put all of its CT-114 Tutor jets on "operational pause" after a pre-flight check detected a problem before a practice flight on Friday at the Bagotville International Air Show in Bagotville, Que.

Sub-Lieutenant David Lavallee, of 1 Canadian Air Division in Winnipeg, said Sunday that the problem was detected in a component of the ejection seat system called the Ballistic Disconnect Link, which is designed to come apart if a pilot ejects from the aircraft.

Lavallee said the exact nature of the problem is still unclear, but the fleet will remain grounded until an investigation by the air force's director of flight safety is complete.

"This is just a precautionary measure to ensure the safety of our people while the investigation is being conducted," Lavallee told CTV.ca in a telephone interview.

The grounding affects all 25 of the air force's CT-114 Tutors, but it does not affect any other air force operation or mission, he said.

Lavallee said he did not know if the Snowbirds have been forced to cancel any upcoming appearances.

According to their home page on the Defence Department's website, the Snowbirds are next scheduled to take to the skies on June 17 in Baddeck, Nova Scotia.

"It's unfortunate that this type of thing happens during the air show season, but at the end of the day our top priority is always the safety of our personnel, the passengers and also the spectators at air shows," Lavallee said. "So the investigators are going to take whatever time they need to look at the problem thoroughly and make any recommendations and take any actions that they feel are necessary. We're just not sure how long it's going to last."

The team usually has a packed schedule of air shows that takes them across North America well into October, but their aging planes have raised safety concerns.

A Defence Department news release said the problem is unrelated to false-lock issues previously experienced with the aircraft's lap belt.

In 2007, Capt. Shawn McCaughey died after his seat belt malfunctioned when he was flying upside down during an air show rehearsal in Montana, causing him to fall out of his seat and lose control of the jet.

Experts have raised concerns that the jets are jeopardizing the safety of pilots because they are about a decade past their best-before date.

The planes began flying in 1963 and first appeared in air shows in 1971.

Defence Department officials have said they would like to keep the planes in the air until 2020, which will cost about $100 million in repairs and upgrades.

However, as far back as 2003, military officials recommended the planes be immediately replaced.