I never quite had the nerve to ask Judy Leden whether I could examine her shoulder-blades. But I'm convinced that X-rays would disclose the vestiges of wing-bones. How else can you explain her obsession with doing nothing much else over the past 13 years but float through the firmament in a hang-glider or microlight, hot-air balloon or paraglider?
The funny thing is that a lot of people think she's as normal as a pigeon in Trafalgar Square. The Queen did. She bunged Leden an MBE in 1989 for services to hang-gliding. Britain's liberated women reckon she is a role model for achievement, so she collected the Cosmopolitan/Clairol Sportswoman of the Year award. Various august bodies, from the Royal Aero Club to the Federation des Pilotes Europeens, have given awards for her aerial exploits. Citroen has sponsored her for the past four years.
Leden herself admits that fantasies of flying send her to sleep every night - 'goodness knows what a psychiatrist would make of my dreams' - and although she wouldn't want to be reincarnated as a bird ('too hard a life') she goes misty-eyed at the prospect of becoming a condor or an eagle for just a couple of months. 'I would love to discover how they know just where the best part of a thermal is, and get just the right angle of bank, and toss off the turbulence the way they do.' Hmm. Maybe a cuckoo would be more appropriate.
But you can't help thinking that an eagle wouldn't mind being Judy Leden. The world's best female hang-glider has a high life in more ways than one. Over the past few years, she has donned her 30ft wings and crossed the Channel, jumped off the snow-covered peak of Cotopaxi (5,896 metres) in the Andes and flown down Kenya's Rift Valley. She does not even bother to find a job that will fit in with her sport. Since the day she discovered hang-gliding while training to be a nurse in Cardiff, Leden, now 33, has not allowed anything (except a short, sad marriage) to interfere with her sky larks. And she is as happy as a hummingbird.
'It makes me a solitary person,' she admits. 'All I want to do is fly. Even in 10 years' time I shall still be flying.'
Don't people ask when you're going to get a proper job? 'Yes, all the time. But why should I?'
Why indeed. Especially as she has just discovered a new aerial interest that has pushed even hang-gliding, the love of her life, into the background. Her very first try on a paraglider last year resulted in a world women's open distance record of 128km. She finished fourth in the first leg of the British trials, beaten only by the very best men, and looks certain to secure a place next week in the British team for the World Championships in Verbier in August.
She confesses: 'I am still a novice. But it is very similar to hang-gliding in many ways. Though things don't happen so quickly, you have to make the same decisions about thermal climb rate and so on, and there are lots of subtle things that you learn over the years. A lot of the top pilots have come from hang-gliding.
'Paragliding is much easier to learn. By the end of a day's lesson, you are doing solo flights. For me, discovering it is like having another injection of enthusiasm. It is nice to have something now which demands a steep learning curve.'
There are now 4,000 paragliding pilots in the UK and it is growing fast, but the sport is already huge in Germany and Switzerland. Unlike a hang- glider, which has a rigid wing, the paraglider is made of spinnaker material and looks like a bent surfboard in the air. The pilot sits as if in an armchair, and controls the direction and speed by brake handles on the ropes. In competitions, everyone takes off together and the hundreds of bright parachutes floating through the sky look like the sudden moulting of a giant bird of paradise.
So what of hang-gliding, the sport that made her famous? Is the affair over? 'It's certainly taken a back seat for the time being,' Leden acknowledges. 'Whenever it's possible to paraglide, that's what I shall do.' She's so serious that she will relinquish the British women's hang-gliding title she has held for the past six years, and instead spend three weeks in the Alps preparing for the world paragliding event. 'I know the thermals there,' she says as if renewing acquaintances with family friends.
But it is not yet time to turn the hang-gliders that litter her stairs ('the estate agents were really puzzled when I specified what was vital in the house I was looking for') into a communal bird-watching hide. For a start, Leden intends to regain the women's world title she lost in Japan this year. 'I don't want to sound boastful, but I know I'm the best female hang-glider in the world.' And she is planning a unique feat later this year that has attracted a National Geographic film crew.
Leden is keeping quiet about the project. But don't expect any spectacular high-level stunt unless she is wearing her trusty wings. For the woman who spends most of her life in the air is terrified of heights. 'I don't like them at all,' she confesses. 'I couldn't go to the edge of Beachy Head and look over, unless I was on all fours. I would be too scared. But ask me to jump off with a hang-glider or a paraglider, and it's no problem.'