Dilip Sarkar, a policeman, believes he has found the crashed Spitfire, which has lain buried in northern France for more than half a century, and he thinks it could reveal what brought it down.
Bader believed he collided with a German plane during a dogfight. As his Spitfire plummeted towards the ground Bader - who had lost both legs in a crash before the war - unstrapped one of his artificial limbs to bail out.
Mr Sarkar, 34, has discovered fragments of wreckage from the plane in a field at St Omer - three miles from the spot where Bader parachuted to the ground and was captured.
After a year trying to trace the wreckage with Dr Bernard-Marie Dupont, who works at a hospital in Lille, Mr Sarkar intends to mount Operation Dogsbody - named after Bader's radio call sign - to recover the plane.
They want to restore the Spitfire in Britain and take it back to France for display.
"The Spitfire came down from 24,000ft so it could be buried 15ft below ground," said Mr Sarkar, from Worcester. "Only five Spitfires were shot down in northern France that day and this was the only aircraft which crashed at St Omer.
"We've found eye-witnesses who saw Bader parachute to the ground and traced the people who helped him escape from the local hospital - they still live in the same house where they hid him. One man even remembers playing as a child in the crater where the plane crashed.
"All the evidence points to this being Bader's Spitfire but until we find a manufacturer's plate bearing the serial number W3185 we will not be absolutely sure. It's bound to be knocked about a bit but the soil in the Pas de Calais is quite soft. Its like going fishing - until you've been you don't know what you will catch. The fact that it's Bader's Spitfire is of paramount importance."
Mr Sarkar has interviewed British and German pilots who were involved in a huge dogfight which led to the capture of Britain's most famous flying ace on 9 August 1941.
Bader's "wing" blazed the trail as more than 100 Spitfires attacked Gosnay power station in northern France.
Bader claimed part of his Spitfire's tail disintegrated when he collided with a German aircraft which he had not seen. Records show no German pilot claimed to have shot down Bader and although there were many anti-aircraft batteries in the area at the time none claimed to have shot down a spitfire. German pilots' combat reports are inconclusive.
Mr Sarkar intends to publish a book in October about Bader's wartime Spitfire wing which will throw new light on the mystery. "It was an incredibly huge dogfight with more than 70 German 109s in the vicinity," said Mr Sarkar.
"Air Vice Marshall Johnnie Johnson wrote in his log book 'more opposition than ever before'. Johnnie said he had never been so frightened in his life. He said there were so many German aircraft in the sky you didn't think about shooting anyone down - you just wanted to get the hell out of there. It was a terrible mess - a complete maelstrom."
Mr Sarkar has obtained previously unpublished pictures of Bader joking with German fighter pilots after he was captured. The Germans wanted to meet him so much they took him from the hospital in St Omer to their base in Audembert, northern France.
Bader was entertained there before being taken back to the hospital from where he escaped. He was later recaptured and remained a prisoner of war until 1945.
Mr Sarkar has spent 13 years working for West Mercia police. He has written five previous books on Spitfires and helped unearth the wreckage of more than a dozen wartime aircraft which crashed in Britain.
His interest in Bader came when at the age of eight he saw the film Reach for the Sky which tells how Bader became the most famous pilot in the Battle of Britain after losing both legs aged 21.
"I used to watch my uncle make huge Spitfire models on the kitchen table and once I'd seen Reach for the Sky I was hooked," said Mr Sarkar.
"It's an awesome story because Bader had such pulverising dynamism. He was an extremely ambitious and charismatic man but his greatest strength was that he led by example - everyone tried to imitate his leadership."
Bader was born in 1910 and died in 1982. He joined the RAF as a cadet in 1928 and was well known for his dare devil stunts and acrobatics. He had his legs amputated in December 1931 after crashing while buzzing a flyers' clubhouse.