It's the confession that no excavation team ever wants to make – that its search has come up empty. But for Spitfire hunters in Burma, who have been on the prowl since early January for dozens of second-world-war-era British fighter planes, that seeming admission came on Friday, when archaeologists were forced to cancel a news conference after their search turned up not planes but cables and pipes instead.

The British-led archaeology team, headed by the Lincolnshire farmer and Spitfire enthusiast David Cundall, has been on the hunt for as many as 140 fighter planes believed to be buried in three sites around the country, with 36 of them supposedly buried close to the runway at Rangoon airport. Armed with mechanical diggers and quite a lot of hope, the 21 archaeologists have spent the past fortnight digging up various holes around the airport looking for the giant crates reportedly housing the planes.

But all the team has found so far is bundles of electric cables and water pipes, a retired Burmese geology professor who has been involved in the Spitfires search told the Associated Press. "We haven't stopped [searching] and we cannot stop," said Soe Thein. "It is just a delay in our work."

No map exists with details of where exactly the planes might be.

Archaeologists working on the dig as well as a spokesman for Wargaming.net – a video-games firm backing the search – have admitted there are no planes in the spots where they have been digging. However, Cundall – who has spent the past 17 years campaigning to find the Spitfires and is now leading the dig – insists that the excavation teams are looking in the wrong places.

The Spitfire search was green-lighted in October after the Burmese government gave Cundall and his local partner exclusive rights to the three sites believed to house the buried Spitfires. The 62-year-old farmer is said to have begun the hunt for the planes nearly 20 years ago after overhearing American veterans mention that they had buried the planes in Burma.

He has since collected various accounts from eyewitnesses, including both American and British veterans, in order to aid his search, and has been accompanied by 91-year-old Stanley Coombe, who claims he saw planes being buried in 1945, and who flew to Burma from Britain to observe the excavation.

The Spitfire – a single-seat fighter plane – earned worldwide recognition for helping Britain beat back enemy bombers during the war. Some 20,000 were built and today as many as 140 are thought to have been buried in crates in near-pristine condition in various sites around Burma by American engineers in 1945. It is believed that the planes were buried either to get rid of them entirely, or so that they could not be used by Burmese independence fighters.

Around one-third of the 140 planes are believed to be on the grounds of Rangoon airport, where a ground-penetrating radar earlier revealed a heavy concentration of metals. Other Spitfires are said to be in Myitkyina in Kachin state, where another team has been digging but whose hopes of discovery were recently dashed after a buried crate revealed so much muddy water that archaeologists said it would take weeks to pump out.

Cundall has said he aims to restore any Spitfires unearthed in Burma back to flying condition in the UK.