The U.S. Air Force F-35 demonstration team will visit Ottawa in September on the eve of this fall's federal election — just as the competition to replace Canada's aging CF-18s starts heating up.

The stealth fighter is one of four warplanes in the $19 billion contest, which was formally launched with a request for proposals by the Liberal government on July 23.

Earlier this summer, the Department of National Defence caused a stir by allowing the Lockheed Martin-built jet to take part in an airshow at the RCAF's principal fighter base in Eastern Canada in Bagotville, Que.

The Aero Gatineau-Ottawa air show will host the jet Sept. 6-8 in the nation's capital. The other competitors to replace the CF-18s — the Boeing Super Hornet, Airbus Military's Eurofighter Typhoon and Saab's Gripen — are not part of the air show's program.

The Opposition Conservatives have long favoured F-35s as a replacement for the CF-18s and made an attempt to buy them while still in power — but development delays, uncertain costs and complaints from the auditor general scuttled the plan. During the election campaign in 2015, the Liberals pledged not to buy the stealth fighter — a position they have since abandoned.

A 'mature aircraft'

Officials with the Bethesda, Maryland-based Lockheed Martin, the world's largest defence contractor, conducted a background briefing on Tuesday to tout its planned bid, pointing out that the warplane — which has been well over a decade in development — is now in service with eight nations and has even flown combat missions with the U.S. Air Force, the Marine Corps, the Royal Air Force and the Israeli air force.

"This a mature aircraft," said a company official who was authorized to speak with the media only on background.

Critics and competitors have slammed the stealth fighter over both its upfront price tag and the ongoing cost to maintain it.

Lockheed Martin officials insisted Tuesday that by the time Canada is ready to buy its new fighters — roughly in 2022 — the purchase price is expected to be lower than US $80 million per plane and the per-hour cost of maintaining and flying it will be reduced to US $25,000, which would be a 25 per cent drop from the current figure.

The Liberal government intends to buy 88 fighters and hopes to have all of the bids in by next spring and to make a decision on which warplane wins by 2022.

Lockheed Martin's competitors have suggested that the contest was tilted in favour of the F-35 through the way the air force's requirements were weighted.

In May, the federal public works department amended some of the criteria for industrial benefits to ease concerns expressed by Washington that the F-35 might be penalized because the program structures its returns differently.

The Trump administration had threatened to pull the stealth jet out of the competition.

Under traditional rules, the winning bidder on a Canadian defence contract must spend a sum equal to the value of the contract with Canadian companies. The F-35 program, meanwhile, sees countries pay regular fees to be part of the warplane's development; in turn, companies in those countries are allowed to bid on F-35 contracts without a guarantee they'll be selected.

To date, over 110 Canadian firms are doing work on the F-35 program for a total contract value of US $1.5 billion.