A somewhat beaten-up test model used in the development of Canada's much vaunted but secretive Avro Arrow fighter jet has been found covered in zebra mussels upside down on the bottom of Lake Ontario, expedition leaders announced Friday.

The tantalizing discovery of the model, between 30 and 60 metres underwater, is the first such find since the federal government killed the Arrow program in 1959, sparking a bitter debate about the demise of what was once considered one of the most advanced combat jets in the world.

"It wasn't just about finding something lost: For generations, the Arrow story has fascinated many of us and has become something dear to many Canadians," said John Burzynski, CEO of Osisko Mining and expedition leader. "It lingers in the Canadian psyche as to what this could have been."

The find is especially significant because the aircraft themselves, along with almost everything associated in producing them, were ordered destroyed when the program was scrapped, throwing thousands of people out of work. In addition, everything about the jet and its development was classified.

"This was all a secret program that nobody knew was going on when it was going on," Burzynski said. "Unfortunately, a lot of the records are partial and spotty."

Explorers with the OEX Recovery Group spent two weeks spread out of the last several months searching for the free-flight models used as part of final design testing of the Arrow off Point Petre, south of Belleville, Ont., between 1955 and 1957.

Using a remote operated vehicle and sonar imagery, they found booster rockets used to launch the models, enabling them to narrow the search area and leading to the discovery. Explorers believe the recovered Arrow free-flight model -- one of nine believed to be in the lake -- is one of the later versions.

Photographs and video indicate the nose was bent or damaged on impact, said David Shea, with Kraken Sonar Systems. However, one of the characteristic triangular wings of the one-eighth scale model -- about three metres long by two metres wide -- is fully intact, and some of the paint appears to have survived, he said.

The plan now, besides searching for the other eight models underwater, is to try to get divers down to remove some of the mussels and inspect the find more closely as part of plans to bring it to the surface.

Expedition archeologist, Scarlett Janusas, said recovery will be delicate to ensure no further damage is done. The plan is to excavate around the model and build a cradle to get it to the surface, where it will have to be put into a container and kept wet.

It will then require cleaning and stabilizing to ready it for display, either in the Canada Aviation Space Museum in Ottawa or National Air Force Museum in Trenton, Ont.

The program to develop and build Canada's first and only supersonic interceptor, just as the Cold War began roaring to life, was aimed at countering potential Soviet bomber attacks in North America's Arctic.

The reason the Conservative government of then-prime minister John Diefenbaker cancelled the Arrow -- as attention turned toward defending against the emerging threat of an intercontinental missile strike -- has been the subject of years of speculation.

What's clear is that the decision, branded by some as Canada's worst research and development disaster -- prompted many who worked on the program to head to the U.S., and ended the country's military jet development ambitions.

Burzynski refused to wade in the debate around the wisdom of a decision he said must have left the "bitter taste of defeat" in the mouths of those who had worked on the showcase program. But one thing, he said, is certain:

"The Russians did not sneak into Lake Ontario and pick up the models back in the '50s like a lot of people thought they did."