The staggering multibillion-dollar purchase price means the Conservative government can only afford 65 of the multi-role stealth fighters.
The number — Canada currently has 79 aging CF-18s — stretches the ability of the air force to meet its commitments, says a series of briefings given to the air force chief last year.
Internal air force memos from the fall of 2010 lay out the "potential for NO pilot training in Canada."
A separate briefing in April 2010 says the F-35 fleet size is "constrained" by cost and other factors.
The presentations, obtained by The Canadian Press under access to information, rank U.S. Air Force training or a contracted "fee-for-service" approach higher than doing it in Canada.
Defence Minister Peter MacKay has said 65 fighters are more than enough to meet Canada's needs, but the briefing raises questions about that because the air force must keep 36 fighters on standby for North American air defence and another dozen for training.
The spring 2010 assessment, written before the government announced its intention to purchase the jets, suggested the air force "optimize operational capability by not employing (a) portion of the fleet for training."
The presentations rank training with either the U.S. Air Force — or a contracted "fee-for-service" approach — as better than doing it in Canada.
Getting instruction from the Americans would provide a "rich" level of experience, but still require the commitment of Canadian F-35s. Allowing an outside agency to do the training would allow the air force to "maximize" the number of aircraft in its fleet.
Under the proposal, pilots would continue to receive their initial qualification in the country, but go elsewhere for advanced training.
The spring 2010 briefing suggested initial overtures to the F-35 Program Executive Officer, the U.S. military officer in charge of the program at the Pentagon, were "positive."
A spokesman for National Defence said Monday that no decision has been made.
"The Royal Canadian Air Force (RCAF) is currently reviewing available options and will choose the option that best meets the needs of Canada's future fighter pilot training," said Evan Koronewski in an email response.
"Canada may exercise the option to participate in a JSF Program Office managed international Pilot Training Centre (PTC). Any decision on how and where this training is conducted will be made with full consideration for specific Canadian training requirements."
Last year, MacKay and his former Parliamentary secretary Laurie Hawn announced the 65 F-35s would be split with 24 planes each at 3 Wing at Bagotville, Que. and 4 Wing in Cold Lake.
There would be training squadron, they insisted, "at a location to be announced in the future."
The plan raises questions about the future of the air force's tactical operational fighter squadron, headquartered at Canadian Forces Base Cold Lake, Alta. The trainers at 410 Squadron run one fighter pilot course every year, graduating about 20 pilots.
The training program consists of nine months of ground school, including flight simulator flights, as well as operational flying. The flight school has been doing advanced training for the air force since the 1960s.
"Until such time as a training solution is decided upon, it is not yet possible to assess the impact, if any, on the OTU (Operational Training Unit) at 4 Wing," Koronewski said.
The U.S. has expressed doubts about whether Canada would buy enough stealth jets in a WikiLeaks cable, dated Dec. 7, 2004.
The classified diplomatic cable noted that even with the current NORAD allotment, Canada is hard-pressed to defend its own cities on a 24 hour, seven-day-a-week basis in times of crisis.
"If cued and pre-positioned at a high-state of readiness, the Canadian air force could cover Vancouver, Edmonton-Calgary, Ottawa-Montreal, and Toronto," said the leaked document. "This would leave almost no capability to provide alert aircraft for Winnipeg, Halifax — or Quebec City."
It is unclear whether the cost of farming out F-35 flight training is factored into the estimated $9-billion-to-$14 billion purchase price — or the anticipated $7 billion-to-$15 billion sustainment costs.
The briefing also highlights some of the technical challenges facing the aircraft, including the need to install drag chutes for short runway landings and to develop an air-to-air refuelling probe. Both were considered minor modifications.