IN 1933, a young aviation enthusiast wrote to Sir Albert Ball, father of Nottingham's First World War air ace, querying the 44 kills credited to the dead hero.
Sir Albert, who spent much of his later life preserving the memory of his son's deeds, replied politely, but firmly, to put the challenger in his place.
"Those who knew him (Albert) know that he would take credit for nothing that was not absolutely correct. But for a young man who knows nothing of the Flying Corps and who would only be in short trousers when the war was on, to suggest the RFC would inflate numbers of victories is, in my opinion, beneath contempt.
"Thank you very much for you good wishes, which I very much appreciate."
The letter was sent to G A Brookfield of Virginia Water, an affluent part of Surrey, from Sir Albert's Wollaton Park home.
It is now in the collection of historian and author Peter Cooksley.
It is included in his new book The Air VCs of the First World War which, quite naturally, includes a chapter on Albert Ball.
Officially, according to the London Gazette announcement of his Victoria Cross in 1917, Ball destroyed 43 German planes and one balloon.
But the writer suggests that new research puts the figure at 67 victories, including aircraft forced to land or "seemingly rendered out of control".
Whatever the truth, there is no disputing Ball's place in Cooksley's gallery.
The story of young Albert, a celebrity of the conflict before he was 20, dead before he was 21, is well documented.
He was one of only 19 recipients of the Victoria Cross in the First World War to come from the ranks of the RFC, out of more than 600 awards during the war.
Each one has a fascinating story to tell and Cooksley sets them out in an accessible, measured style.
His collection begins with William Rhodes-Moorhouse who pressed home a single-handed bombing attack at treetop level, flying through a hail of rifle and machine gun fire which riddled his aircraft, and him, with dozens of bullets.
Aged 28, he later died in hospital clutching a photograph of his one-year-old son.
Argyll and Sutherlands Gunnery officer John Liddell was driven by the horrors of trench warfare to swap his uniform for the wings of the RFC.
In August 1915, his two-seater RE5 was attacked behind German lines and raked with machine gun fire.
Liddell's right thigh was torn open, flooding the cockpit with his blood.
Temporarily losing consciousness, the aircraft plunged into a 3,000ft dive.
Somehow he regained his senses and, remarkably, he had the presence of mind to scribble a note to his navigator saying he would try to reach the Allied side rather than ditch and risk instant capture.
The courageous decision saved his comrade but denied Liddell instant medical attention and the terrible injury would eventually cost him his life.
He was 27.
All 19 stories in Peter Cooksley's book are compelling accounts of extraordinary bravery – but the deeds of Australian Frank McNamara are singularly remarkable.
Part of a four-plane attack on a Turkish rail junction in Palestine, he was badly wounded by shrapnel from one of his own bombs.
As he turned for home he spotted fellow pilot David Rutherford on the ground near his downed aircraft... with a platoon of Turkish cavalry charging towards him.
McNamara landed his single-seat plane and Rutherford climbed on to the wing in a bid to escape.
But because of his wound and his comrade's weight, McNamara crashed attempting to take off.
Still the two men refused to give up.
They went back to Rutherford's plane and, while holding off the Turks with their revolvers, managed to get that aircraft started.
Drifting to the edge of consciousness because of the loss of blood, McNamara took the controls, lifted off and managed to nurse the aircraft 70 miles to safety.
McNamara, who would survive the war to become an Air Vice Marshall, became the only Australian airman to win the VC after several officers had recommended him, including Rutherford who wrote... "the risk of Lieut MacNamara being killed or captured was so great that even had he not been wounded he would have been justified in not attempting my rescue – the fact of his already being wounded makes his action one of outstanding gallantry – his determination and resource and utter disregard of danger throughout the operation was worthy of the highest praise".
The Air VCs is published by Sutton, priced £10.99.