Diving into the past: Doomed Second World War RAF bomber discovered at the bottom of the sea... 70 years after it crashed Flight W3998 crashed during take-off in December 1941 - killing eleven RAF airmen and leaving only four survivors Aircraft, which had been missing for seven decades, was discovered in the sea off Plymouth Sound, Devon, by professional diver Danny Daniels It was hurtling towards the water in pitch darkness, loaded with heavy equipment and eight extra men. The World War II allied warplane burst into flames on impact - claiming the lives of eleven RAF airmen and leaving only four survivors. From that day in December 1941, what happened to the doomed Sunderland bomber off Plymouth Sound, Devon, has remained a mystery. But now, more than 70 years later, the ghostly remains of Flight W3998 have been uncovered - thanks to a chance discovery by ex-Royal Navy clearance diver Danny Daniels, who taught Prince Harry how to dive. Discovery: Ex-Royal Navy clearance diver Danny Daniels dives among the wreckage of Flight W3998, which crash-landed off Plymouth Sound, Devon, more than 70 years ago Mystery: The doomed RAF airplane crashed during take-off - killing eleven men and leaving only four survivors. Above, Mr Daniels finds a huge propeller belonging to the aircraft History: Mr Daniels found parts of the wrecked Sunderland bomber, including a radial aero engine and a propeller, during a route drift dive near the former RAF Mountbatten airbase He found the wrecked airplane, - which will be shown on BBC documentary series Inside Out tomorrow evening - during a route drift dive near the former RAF Mountbatten airbase. During the Second World War, the airbase was home to a squadron of Sunderland bombers using the sheltered waters for frequent forays over the Atlantic on seek-and-destroy missions against menacing German U-boats. Nicknamed "flying boats" due to the large pontoons that enabled them to take off and land from the surface of the water, the Sunderland warplanes were under constant threat of aerial attack from the enemy's long-range Condor reconnaissance planes. But it wasn't just the Luftwaffe that posed a potentially fatal danger. Powerful: The Short Sunderland aircraft (similar to the one that crashed) was one of the most powerful and widely used 'flying boats' during the Second World War Take-off and landing could prove equally as hazardous - with many aircraft falling victim to accidental crashes during the war. Piloted by RAF Flight Lieutenant David "Digger" Fletcher, flight W3998 is believed to have crashed during take-off after being overloaded with extra equipment and fifteen men - eight more than normal. Victim: Flight Lieutenant David 'Digger' Fletcher was piloting the airplane, which crashed after being overloaded with extra equipment and 15 men Its crew had enjoyed a two-day stopover at Mount Batten before they were due to fly on to Gibraltar for a Christmas break, prior to a posting to train new Sunderland flight crews. As the heavily-laden warplane thundered along its flare-lit runway in pitch darkness, its four powerful Bristol Pegasus engines struggled to lift it into the air. Flt Lt Fletcher, who was fearful of striking the semi-submerged breakwater, was forced to abort his approach. The 28-year-old Australian taxied into position for a second attempt - unaware that impending disaster was only moments away. Lifting clear of the anti-submarine boom and rising above the breakwater, the bomber's engines - unable to cope with its extra payload - suddenly stalled and the plane dropped from the sky, bursting into flame on impact with the water below. Flt Lt Fletcher was killed instantly - with ten others declared 'missing, presumed dead'. Only four men survived. Mr Daniels, 52, who was awarded an MBE in 2005 for Services to Diving, discovered the twisted remains of the doomed flight more than 70 years after it was reported missing at 4.20am on December 21, 1941. 'One of our boats was quiet the week after the initial finding, so I decided to investigate further and just two minutes into the dive I found myself alongside a large radial aero engine complete with a huge propeller,' said the former Joint Services chief diving instructor. Making his way through a thick band of kelp, Mr Daniels continued his search and soon found a growth-encrusted piece of aircraft cowling - concealing a bank of what initially appeared to be eight pistons. Gliding: The aircraft had large pontoons that enabled it to take off and land from the surface of the water. Above, a Sunderland flying boat soars over the Eddystone lighthouse, about 12 nautical miles from RAF Mountbatten in Plymouth Sound, Devon Fighter: The Sunderland bombers were under constant threat of aerial attack from the enemy's long-range Condor reconnaissance planes 'Sheltered': An aerial view of RAF Mount Batten in Plymouth Sound, Devon, during the base's time in active service. He came to the conclusion that the remains marked the resting place of a German fighter plane. It wasn't until a subsequent dive, when a colleague spotted a second propeller and then Mr Daniels discovered a ninth piston, that he began to have doubts. 'Using ground markers and a compass, I carried out a painstaking box system search technique that revealed an AMK12 anti-shipping exercise mine, a fair amount of British .303 ammunition, another engine and two more props.' he said. Further investigation of the site also uncovered the cockpit steering gear and a pair of machine guns. Expert: Diver Danny Daniels, who taught Prince Harry to dive, discovered the twisted remains of the doomed flight more than seven decades after it was reported missing at 4.20am on December 21, 1941 However, it was a small piece of a broken dinner plate bearing the RAF's insignia that was to prove crucial - allowing Mr Daniels and local historian Darell Jago to establish that the ghostly remains belonged to the missing Sunderland bomber. 'The simple reason this Sunderland was never located was that it came down more than twice the distance as stated in its RAF accident report,' said Mr Daniels. Flt Lt Fletcher's niece, Lois Porters, 75, from Brisbane, Australia, said: 'The fact that the wreck has at last been found and can now be recognized as a War Grave is important to us and other family members of the crew. 'We're grateful that a positive identification has finally been made and knowing where they fell gives everyone closure.' Evidence: This small piece of a broken dinner plate bearing the RAF's insignia proved crucial to the investigation Conclusion: Local historian Darell Jago (pictured) helped Mr Daniels establish that the ghostly remains belonged to the missing Sunderland bomber Mrs Porters has kept letters of condolence sent to her mother Essie by Wing Commander WG Abrams, which show the high esteem in which her uncle was held. Digger had the natural gift of instilling cheerfulness in all around him. As you know, he has done some fine work since joining the Squadron in 1940. We were sick at him being sent to the Mediterranean but this loss is a big one for us. He was about to leave when the accident happened. Flt Lt D. A. Steward told Essie: 'Dave was quite the bravest man I ever knew and he was my staunchest friend. Death: The crash instantly killed Flt Lt Fletcher - with ten others declared 'missing, presumed dead'. Above, Mr Daniels at the Plymouth grave of Flt Lt Fletcher Buried: Flt Lt Fletcher's body was found washed ashore at nearby Whitsand Bay on Christmas Eve, 1941. He was buried at Ford Park Cemetery in Plymouth I shall never like anyone so much as I did old Dave, even if I could. His motto was always "Engage More Closely" and I have little doubt that had he been in another fight it would have been the hun who would have gone away with a flea in his ear. Remember, he gave the hun plenty to think about when he was operating. Mr Daniels believes that a number of mitigating factors were responsible for the tragedy. Tragic: Flt Lt Fletcher's death certificate Hero: Flt Lt Fletcher's niece Lois Porters, 75, has kept letters of condolence sent to her mother Essie by Wing Commander WG Abrams, which show the high esteem in which her uncle was held 'Knowing where they fell gives everyone closure': Mrs Poters and husband Alan are gratefull that a positive identification has finally been made 'David Fletcher was a crack pilot with thousands of missions under his belt, but the fact he was operating in unfamiliar waters, in the darkness, with an overloaded aircraft, combined with the additional hazard of the breakwater would all be contributing factors,' said Mr Daniels. 'Perhaps if not for this combination of circumstances the crew may well have seen out their time in Gibraltar until the war's end.' The body of David James "Digger" Fletcher of 201 Squadron was found washed ashore at nearby Whitsand Bay on Christmas Eve 1941 and he was buried at Ford Park Cemetery, Plymouth. The story of Flight W3998 will be told on BBC Inside Out South West tomorrow at 7.30pm. Yorkshire-born Harry Lodge was a 19 year-old radio officer on flight W3998 and recalled his memories of the crash during an interview with a local newspaper in 1983. Normally we never wore lifejackets. They were considered cissy,' said Mr Lodge, who passed away in 1993 aged 71. I somehow felt uneasy that night. It was the middle of December and the night was as black as the ace of spades. One of my colleagues saw me putting on my lifejacket and asked "What the hell are you doing?" Survivor: Harry Lodge, pictured post-crash, was left with a scar on his bottom lip from where his teeth pierced his skin during the crash I persuaded him to put his jacket on too. I remember taking off from the water and feeling relieved that we were away safely. But the next thing I was in the water a mile out to sea off Plymouth Sound. We, plus one other crew member who was also wearing his jacket, were the only ones to survive. Surrounded by 2,000 gallons of fuel blazing fuel and with hands suffering from severe burns, Mr Lodge not only had to contend with his injuries caused during the crash but also those inflicted by the rescue boat during its search for survivors. Actually the boat ran over me. I rolled aside and pushed the hull away. It nearly took my fingers off then they spotted me and I was picked up. We were apparently in the water for an hour because of the time taken to get clearance for the anti-submarine nets to be lifted. Mr Lodge remained on the hospital's danger list for six months with the fractured skull he received during his collision with the rescue boat leaving doctors doubtful he'd survive. Alongside him and with the relatively minor injuries of a broken arm and collarbone was the crewman he'd persuaded to wear a lifejacket. Bearing lasting scars across the temple from his head injuries, and his lower lip from the loss of his teeth, Harry Lodge later returned to active duty and was commissioned as a pilot officer training on flying boats. Switching to Wellington and Lancaster bombers in the latter stages of the war Lodge was demobbed in 1946 and pursued a successful career in civil aviation. Joining BOAC as a radio officer he worked as ground staff at London Heathrow before his eventual retirement as Manager for Air Traffic Services with British Airways.