"This is probably the most active they've been since the end of the Cold War," said Maj.-Gen. David Wheeler, commander of 1 Canadian Air Division and the officer overseeing his country's role in exercise Amalgam Dart.
U.S. Admiral William Gortney, commander of the North American Aerospace Defence Command (Norad), said the Russian military is far better equipped than its Soviet precursor and is being used to send other countries a message.
"It's not just the frequency, it's where they're flying, (although) they're adhering to international standards," he said Thursday.
Gortney said that at the same time a Malaysian airliner was shot down over Ukraine last summer, the Russians had military aircraft flying down the English Channel and in the Arctic off Alaska and Yukon.
"They're messaging us with these flights that they're a global power — which shouldn't be a surprise, we do that too," Gortney said.
"My concern is, what is their intent if the situation escalates somewhere? How will they employ this capability?
"This is why this exercise is so important."
U.S. military figures acknowledge at least 17 Russian military aircraft approached North American airspace in 2014, including bombers, tankers and fighters. Not all records of such flights are released.
The flights restarted in 2007 and recently increased, said U.S. (Navy) Capt. Jeff Davis.
"We noticed an increase in the number of these flights near North America in 2014, which followed Russia's incursion into the Ukraine and Crimea," Davis said in an email. "Much of the increase in 2014 was due specifically to a spike in the summer that we assess is related to training."
Amalgam Dart involves 15 aircraft and 300 personnel from the U.S. and Canada flying out of bases in Alaska, the Northwest Territories and Nunavut. The planes include U.S. F-15 Eagles and Canadian CF-18 Hornets, as well as air tankers and surveillance aircraft.
The practice will also make use of Northern Watch, Canada's electronic surveillance system.
A paper released earlier this week by a military academic suggested the real role of the Canadian Forces in the Arctic will be to support civilian agencies such as the coast guard and the RCMP. Adam Lajeunesse of the Canadian Defence and Foreign Affairs Institute wrote that open conflict in the North is unlikely and the mere presence of the military does nothing to enhance sovereignty.
Wheeler said that may be true, but added that the Air Force is an exception. Civilian forces can only request a foreign plane leave Canadian airspace. Fighter jets can escort it out.
"We will support (other government departments) if necessary," he said.
"But in the air it's totally different. Providing air sovereignty cannot be done by the RCMP or any other civilian organization. It can only be done by the military."
— Follow Bob Weber on Twitter at @row1960
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