There's no secret about what this particular Scotsman has under his kilt. Like me, around 20,000 people are staring straight up it to discover nothing more than a lot of hot air.
The sound of amplified bagpipes is ringing round the valley and when there is finally sufficient heat beneath these vast folds of tartan, this giant piper slowly drifts off towards Mont Blanc.
It's an extraordinary sight - a 156ft flying Scotsman floating over the cuckoo-clock chalets, snow-caked slopes and rocky peaks of Switzerland. But the view is even more impressive from where I'm standing. Because I happen to be in his sporran.
This is not exactly a conventional, purse-shaped sporran, but a wicker basket containing five people plus four tanks of propane which will heat up the air to keep us aloft.