WHAT could be more elemental than thin air? Unfortunately, as we learned in Every Breath We Take: Understanding our atmosphere (BBC4, Monday of last week), air is neither thin nor an element. Gabrielle Walker took us through the history of the realisation that the invisible stuff around us is in fact made up of more than one thing.

First, carbon dioxide was discovered, accidentally, in 1764; then, nitrogen was identified; then finally the most interesting of them all, oxygen, which apparently kills us with every breath we take, but, paradoxically, is the only thing that can give life forms the energy to have more than a single cell.

Without air, there would be no aeroplanes; without aeroplanes, there would be no RAF; and if the RAF did not exist, there would be no call for its élite acrobatic aerial-display team. We heard all about them in Red Arrows: Inside the bubble (BBC2, Sunday).

It was sobering stuff. They hurtle along at terrifying speeds, only six feet apart, depending on split-second reactions to produce patterns with what appears to be absolute precision. It is a kind of ballet, performed in three dimensions, on a limitless canvas. But this is an exceptionally dangerous art. We were reminded that, in 2011, two of the close-knit team of pilots were killed.

The pressure - literal pressure, as the most extreme manoeuvres exert 4g upon the pilots, involving a serious risk of blacking out - and intensity required make this a brief calling. Each year, a couple of the team members move on to other postings, and new ones take their place. The programme's dramatic pattern was twofold: would this year's potentials make the grade; and would the whole troupe pass the annual inspection and be deemed fit to represent the RAF at events throughout the world?

After each sortie, the most rigorous debrief is undertaken, where everyone is candid about how their colleagues - on whom their lives depend - performed. To reduce the potential for personal dispute, and to maintain harmony and cohesion, everyone is identified not by name, but by a number. I understand that several cathedral chapters have adopted the practice.

If a fighter-plane cockpit represents the highest-tech male environment, then the opposite of the same spectrum is clearly occupied by the humble garden shed. The examples exhibited in Amazing Spaces: Shed of the year (Channel 4, Thursday of last week) were anything but humble, though. We saw the heats in two of the categories in this annual national quest - four contenders each in the eco and the unique classes - and they were all extraordinary.

The competition is an explicit celebration of British eccentricity. The sheds included a functioning 16-seat cinema; a huge metal-and-papier-mâché egg, whose next development will be hydraulic legs (its owner wants it to walk around the garden); an exact reproduction of a cabin and dining-room from the Titanic; and one made entirely from empty wine bottles.

The subject-matter was sensational; but the presentation, with the wall-to-wall superlative and cliff-hanging suspense deemed essential nowadays for retaining any audience's attention, left much to be desired.