The forgotten Scot who was the RAF's founding father
As the Royal Air Force celebrates its centenary, there are calls for a Glaswegian to be recognised as its "founding father."
Lt-Gen Sir David Henderson had a distinguished career in the Army, fighting with the Argyll and Sutherland Highlanders in the Zulu and Boer Wars and the Sudan.
But his pivotal role in establishing the RAF in the final year of World War One has largely been forgotten.
It was his proposal, in a seven-page memorandum, which persuaded Prime Minister David Lloyd George to combine the Royal Flying Corps (RFC) - a branch of the Army - and the Royal Naval Air Service into a separate air force.
Sir David wrote in July 1917: "It is difficult to indicate any method of overcoming the present illogical situation of divided responsibility in aeronautics, except by the formation of a complete department and a complete united service dealing with all operations in the air, and with all the accessory services which that expression implies."
Within four months Parliament passed legislation to establish the world's first independent air force, the RAF.
But many histories ignore Sir David's role and credit the first head of the RAF, Viscount Trenchard, as its father.
The officer now carrying out that role, Air Chief Marshal Sir Stephen Hillier, Chief of the Air Staff, disagrees.
A former Kilmarnock Academy pupil who has now swapped fighter jets for a Whitehall desk, he said the work done by his fellow Scot, Sir David, is still to be seen in today's RAF.
Sir Stephen said: "He was here in Whitehall in 1917 and 1918, at those critical stages of the formation of the Royal Air Force, if you like, navigating his way through the bureaucracy.
"And his principles are very much at the core of the Royal Air Force.
"Having been born and brought up in Scotland myself, I'm keen to ensure David Henderson is not forgotten in our 100th anniversary year."
Sir David wrote that if the war continued beyond 1917, a united independent air service was a necessity.
And it was Sir David's vision which made that happen, according to Professor Tony Pollard of Glasgow University.
Prof Pollard said: "The resources were being over-stretched; aerial combat was becoming an accepted form of warfare.
"Prior to that, they had simply been taking planes up with cameras to photograph the enemy.
"And then they start to have to shoot one another down, because you don't want photographs taken of your positions.
"So we get aerial combat, we get aerial bombing, and it becomes so advanced so quickly that it's quite clear we had to have another service."
Sir David was born in 1862 into a fairly affluent Glasgow family.
His father was a joint owner of a Clydeside shipbuilding business.
He entered Glasgow University at the age of 15 to read engineering but left without graduating and went to the Royal Military College Sandhurst.
Over the next 30 years he would serve in most of Britain's foreign campaigns.
Sir David first recognised the potential of aircraft when he saw balloons being used for reconnaissance at the siege of Ladysmith during the Boer Wars at the turn of the 20th Century.
He learned to fly in 1911, aged 49, under the pseudonym Henry Davidson and became the first head of the Royal Flying Corps when it was formed as a branch of the Army a year later.
Prof Dugald Cameron, of Glasgow School of Art, an expert in Scottish aviation, said it was the fact that Sir David could fly which was vital when he challenged the War Office to establish an independent air service.
Senior military figures had initially resisted the idea, but the way the Germans took the war to the air changed their view.
Prof Cameron said: "From 1915 the Imperial German Air Service were bombing Britain.
"First of all with the Zeppelins and then in 1917 with the Gotha bombers and other bombers on the east coast towns and then London.
"And when London was getting attacked from the air - the first time our shores had been breached - the Navy, the traditional defenders of our coast couldn't do it," he said.
Prof Cameron has painted many of the exhibits on show at Glasgow University in a display marking the RAF's centenary - what he called "the photographs which were never taken".
He said the exhibition, in the chapel dedicated to the memory of students and alumni who died in combat, was a fitting way to highlight Sir David's place in aviation history.
Prof Cameron said: "He was a very great man indeed, and Glasgow should be really proud of him.
"I have tried over the years to get the city to take more interest and recognise and honour General Sir David Henderson."