Over the years I’ve been in touch with a number of middle-aged professionals who, despite the success they’ve found in their chosen careers, have asked themselves whether perhaps they should have become pilots instead. Among these correspondents (the fly-curious, we might call them), architects make up the largest contingent. It’s hard to know why this might be. But in the absence of a better explanation, I’ve come to enjoy the idea that both pilots and architects have found inspiration in realms that, despite popular associations with freedom, are in fact unusually constrained: by simple or not-so-simple physics by the corporeal realities of humans; by elaborate rules and strict regulations.

This ‘bonsai’ description of flight’s wonder — of transcendence arising within an endeavour despite, or as a result of, the extreme limitations imposed on it — is also the best way to understand the pleasures of Rebecca Loncraine’s Skybound. Indeed, she laboured under two additional constraints. First, in choosing to write about gliding, she threw overboard the engines that have powered, and perhaps unfairly dominated, generations of books about flying. Second, her discovery of gliding, and the depths of her love for it, came in response to her battle with cancer, which ended in September 2016, when she was 42. The result of her efforts (and those of her mother, Trisha Loncraine, who shepherded this book to publication) is a particularly lovely and poignant work, and a valuable contribution to the literature of flight from a brave young pilot who will sadly never offer us another.

Among the book’s most obvious pleasures are the straightforward descriptions of gliding itself, an activity that, at least on the wings of Loncraine’s clean-lined prose, compares to most people’s experience of flight in much the same way as a beloved old sailing boat a couple of friends might take out on a fine Saturday afternoon compares with an enormous cruise liner.

Take, for example, the joyful vitality of her description of thermal lift, one of several kinds of lift a glider may soar on, and the kind that also produces fluffy cumulus clouds. A glider pilot, she writes, may use ‘thermals as stepping stones to travel across the sky, circling beneath one cloud, on the rising thermal of air that is forming it, to gain altitude and then travelling forward to the next cloud, and so on’.This pilot, for one, may never contemplate cumulus clouds again without smiling at the possibility of flying engineless between the pillars of sun-warmed air that raise them, as a frog might leap between lily pads, but ever higher.

Indeed, the list of places, creatures and phenomena I won’t think of in quite the same way after reading Skybound isn’t much shorter than the book itself. A good portion of the text is a kind of open-hearted travel writing from above, as the author sails over the Black Mountains of Wales, where ‘a shadow passes briefly across a bit of rough ground and then disappears again, like a half-remembered moment’; New Zealand, where the ‘Southern Alps are like some giant unknowable body’; and the Himalayas, where a ‘lake is a dark silvery plain beneath us’. I’ve been to none of these places, yet I now feel I know them, or can at least imagine them, as I might the faces of characters in a favourite novel.

In addition to these landscapes, and their skies and their signature winds, we come to know the community of gliding instructors and enthusiasts who welcomed Loncraine, and whom she embraced. And then there are the birds. Both from the ground and from high in her glider, Loncraine meditates on feathered friends of all stripes: swallows, buzzards, red kites, hawks, eagles and, most memorably, vultures.

The role of birds in her book — as teachers, companions and wisdom-bearing (it’s easy to think) representatives of all that industrial civilisation has taken from us — makes it hard to resist the conclusion that gliding might be the purest form of flight that we can know. Without an engine, after all, the glider pilot has no choice but to seek a particularly close communion with the natural world. It’s a lovely point, and one that Loncraine returns to often, as when she relates the words of a gliding colleague who noted the possibility that vultures, which can spot rising air from the dust and insects that are swept upwards by it, may also use gliders — i.e., us, at our most free — as clues to the location of lift. What a pleasing thought that is.

One of the challenges of writing a broadly appealing book about a subject such as gliding is that the author must often craft technical explanations that are simultaneously accessible, precise and brief. A few professional brows may furrow in response to certain descriptions or phrasings, for example about the relationship between a glider’s attitude and its speed (‘I hold the stick in place to maintain speed, or “attitude” as it’s called’). But no one will mistake this lyrical book for a technical document.

Indeed, if Skybound is a manual for anything, it’s for how to find lift on the Earth in the face of uncertainties and certainties that are never far from any of us, but which Loncraine was forced to confront at much too early an age. I won’t soon forget her meditations on fear and flight, on home and family, on the scars she spied and circled on the Welsh landscape below her, and on the quasi-medical paraphernalia, such as an oxygen-supplying cannula, that echoed her cancer treatments even as they allowed her to fly ever higher. ‘Learning to fly,’ she wrote, ‘is like asking the universe… to let me go into the world to live and soar with joy and the possibility of death.’ It seems safe to conclude that the universe agreed to Loncraine’s request, and that in return it asked only that she leave us with this remarkable book.