On a freezing winter's afternoon, several miles off the Kent coast, a parachute could be seen floating down through the snow.

The pilot hit the icy water and drifted close to a convoy of ships. The sailors on-board could hear desperate cries for help.

They had no idea that the pilot gasping for air was the legendary Amy Johnson.

The first woman to fly solo from England to Australia, she would go on to be remembered as one of the most influential and inspirational women of the 20th Century.

Mystery still surrounds the circumstances of her death, 80 years ago today, near Tizard Bank off Herne Bay.

Several sailors had reported seeing two bodies in the water. But neither Johnson's body nor the so-called "Mr X" were ever recovered.

People couldn't understand why such an expert flyer had ended up so far off course from her assigned destination in Oxford.

There have even been rumours that she was on a secret mission.

While questions remain about the tragic events leading to her death, aged just 37, there is no doubt that Johnson lived a truly remarkable life.

Sandstorms, volcanoes and forced landings

The eldest of four sisters, Amy Johnson grew up in Hull, where her father, John, was a partner in the family fish-processing business.

"Smart and rebellious", she moved to London after graduating from Sheffield University and tried a series of jobs, including working as a legal secretary.

One day, with some free time on her hands, she boarded a bus which took her to Stag Lane Aerodrome in north London.

She was immediately fascinated by the biplanes and took her first flying lesson in 1928. She was awarded her pilot’s licence the following year.

Although very inexperienced, Johnson decided she wanted to beat the world record for flying the 11,000 miles from England to Australia.

She raised enough cash to buy a second-hand Gypsy Moth bi-plane called "Jason" for £600.

Using just a compass, ruler and map to plot the most direct route, she flew over some truly dangerous terrain.

Her daredevil journey involved forced landings in a desert sandstorm and another in a jungle among what she at first feared to be a hostile tribe.

She also flew through tropical storms and had to navigate shock waves from a volcanic eruption.

While terribly lonely when in the air for up to 12 hours a day, Johnson was greeted by enthusiastic crowds wherever she landed to refuel.

Hero's welcome and global fame

Finally, after 20 days of flying, she arrived to a hero's welcome in Darwin, Australia, in May 1930 and while she had failed to beat Bert Hinkler's world record - she had nevertheless achieved global fame.

Over the next six weeks she was treated like a superstar. Women even asked their hairdressers for an "Amy Johnson wave".

At least 10 songs were written about her and fan mail arrived from all over the world.

Johnson was congratulated by King George V, Queen Mary and Prime Minister Ramsay MacDonald - and later awarded a CBE.

The newspapers in Britain called her "Queen of the Air" as she went on to break a number of records, including for the fastest solo flight to South Africa.

In 1932, she married Scottish pilot Jim Mollison and they were dubbed the "flying sweethearts".

The following year the couple made the perilous journey over the Atlantic. Despite crash-landing in Connecticut, they still broke the world record and were embraced by the US public - even meeting President Franklin D Roosevelt.

Johnson's sky-rocketing success also saw her brush shoulders with the likes of Charlie Chaplin and appear in Vogue magazine in 1936.

Yet fame came with a price as her turbulent marriage hit the rocks - in the unforgiving glare of the public eye - and the couple divorced in 1938.

Tragic final flight

The outbreak of the Second World War in 1939 made Johnson reconsider her somewhat flashy public role and in 1940 she joined the Air Transport Auxiliary, an organisation set up to ferry planes around the country for the RAF.

On Sunday, January 5, 1941, Johnson set off from Blackpool Aerodrome on what was fated to be her final flight.

Flying a twin-engine Airspeed Oxford plane in the freezing cold and fog, her destination was RAF Kidlington near Oxford. It was a routine 90-minute journey.

But four hours later she was parachuting into the Thames Estuary, more than 100 miles off course.

The HMS Haslemere was among the convoy of ships at the Knock John Buoy on Tizard Bank that afternoon.

Its captain, Lieutenant Commander Walter Fletcher, valiantly dived into the icy water to try to save one of the two people his crew had reported seeing.

In the end, LCDR Fletcher had to be rescued himself. Tragically, he later died from exposure to the extreme cold and shock at the Royal Naval Hospital in Gillingham. He is buried in the town's Woodlands Cemetery.

Parts of Johnson's plane, her travelling bag, logbook and chequebook washed up later - but she was never found.

How she ended up off the coast of Herne Bay - whether she had indeed been on a secret mission, hit by friendly fire or simply got lost in the bad weather - has never been determined.

A true inspiration

Yet Johnson's courage and determination has continued to inspire.

In September 2016, a bronze statue of the pioneering pilot was unveiled on Herne Bay seafront by the Queen's cousin, Prince Michael of Kent.

Campaigner Jane Priston, who spent months raising money to fund the sculpture, said: “It is about representing the spirit of Amy and we have done that with this piece.”

The RAF Accident Record Card names Herne Bay as the location where Johnson's final flight came to an end.

According to The Amy Johnson Project, the statue, "stands as a monument to women, aviation, engineering and all those who served with the Air Transport Auxiliary during the Second World War and will be a permanent landmark to inspire and educate".

The bronze bust on the town's promenade sees Johnson dressed in early 1930s' flying attire, adjusting her goggles and looking to the horizon.

Etched on her headwear is the quote: "Believe nothing to be impossible."

Find out more about Amy Johnson on The Amy Johnson Project website and via Historic England.

Read more: All the latest news from Herne Bay

Read more: All the latest news from Kent