It was 2017 when two retired engineers started to find strange objects on the bottom of Lough Erne.
Robert Navan and Mike Kingston were surveying the shifting bed of the lake when strange straight objects came into view.
Their story is one of many recounted in a new BBC programme, The Chronicles of Erne.
With more than 150 islands and 500 sq km of water the Erne is a busy waterway for locals and the 350,000 visitors who venture to County Fermanagh every year.
Filmed over a year, this new four-part series charts the passing of the seasons through the eyes of the people who live and work on the Erne.
Catalina pilots provided air cover for Allied convoys in the Atlantic during World War Two and there was an RAF base at Castle Archdale.
Robert and Mike take regular trips out to measure the depth of Lough Erne's shifting bed and share this information with other boat users to stop them running aground.
It was during these trips they started to look for sunken seaplanes.
"In July of 2017 the inland waterways lent us side scan sonar and on the very first day we found objects of interest," said Robert.
Last year, they were joined by a team from the Department of Agriculture, Environment and Rural Affairs to investigate the objects they had discovered.
"American film crews have been over looking for them," said Robert.
"And English divers have been over looking for them with no success."
State-of-the-art sonar suggested the straight objects may be a more mundane discovery - a tree.
However, the programmes shows how a closer look revealed the obvious outline of a plane.
Floating community centre
There's also a group taking care of their own boat to get out on the water.
At Drumgallon, Row The Erne is hard at work repairing a currach, or a 'floating community centre' as it has been described.
A currach is a wooden-framed boat which traditionally was covered in stretched animal skins.
"What's really fantastic about the boat is the people in it, that's what makes the difference," said Olivia Cosgrove.
"What we realised we'd done is create a floating community centre.
"None of us are boat builders, like I'm an accountant, and to put a skin, a 33-feet coat on a boat, is extremely gratifying."
But will it stay afloat and make it across the lake?
Chronicles or Erne will be shown on BBC One Northern Ireland on Monday at 19:30 GMT.