Barbara Amiel was right that one private jet isn’t enough. One jet is always in the wrong place, or undergoing maintenance, or perhaps these days being attacked by eco-activists. So two is the absolute minimum.

Needless to say, the very idea of private jets sends environmentalists insane. Just last week, Just Stop Oil types attacked private jets at Ibiza, splashing paint and glueing themselves to the wings.

The Stay Grounded network, which also campaigns against private jets, boasts on its web site, ‘We’ve come to tell the super-rich the party is over’. This goes to show that much of the eco-extremist anger at private jets has probably more to do with class warfare than the environment. Air travel accounts for an estimated 2 per cent of total global greenhouse emissions. Private jets account for 2 per cent of this 2 per cent, or 0.04 per cent.

Much of the eco-extremist anger at private jets has probably more to do with class warfare than the environment

Is it only the super-rich, as Stay Grounded say, who are in the PJ set? There are certainly more expenses than you might imagine. Buying a jet is merely a down payment on the ongoing costs of ownership. It costs £600 just to land at the private jet port at Farnborough, plus parking. It’s extra if you bring a pet.

A rule of thumb is that after paying pilots, insurance costs, filling up with aviation fuel, hanger fees, technicians, flight attendants, and cleaning and catering contractors, operating an Elon Musk-style Gulfstream G650 costs around a million dollars a month.

Because your jet will only fly you to an airport, albeit to luxurious private terminals like Farnborough, a helicopter might also be necessary for the onward trip to your factory, mansion or yacht. Abramovich’s yacht has two helipads. One for his Airbus helicopter, the other for the pizza delivery helicopter, perhaps.

In the TV series Succession, the media tycoon Logan Roy favoured the Sikorsky S-76-B, a medium helicopter that’s also the choice of the British Royal Family. Figure $15 to 20 million for one of these, depending on the fit-out. And perhaps $100,000 a month in running costs.

But this is a billionaire-class approach. What about mere millionaires? Or those with lesser fortunes who would rather spend it on temporal luxuries than leave it to be taxed by the revenue?

There’s fractional ownership. You can own half a jet, or even 10 per cent. Like a timeshare. A million would buy you perhaps 10 per cent of a light jet, although there’s fuel, pilots and landing fees on top. A few hundred thousand, a small share of a turboprop. Still pretty rich.

For us lesser mortals, I am pleased to report, there are even more palatable alternatives. ‘If you can f*** it or fly it, rent it don’t buy it,’ is the advice of those who privately fly five to six times annually, perhaps to the Alps to ski, or the Balearics for summer sun. A flight in a light jet from London to Geneva is about £5,000 one-way. Malaga is a little more. So a (comparatively) modest budget of £50,000 will buy you four to five return flights a year.  And you can bring your pets.

My own experience of private jetting is I confess fairly limited, although I should like to indulge more in my senescence. I once chartered a modest jet to get me from Paris to Luxembourg, where I was having dinner with the prime minister of that country.  And I once chartered a jet to get me out of Blackpool after a Conservative party conference, which is a sound excuse. It would be indiscreet to acknowledge who signed my expenses claim but I’m duty bound to admit that Rupert Murdoch paid, unwittingly, both times.

I’m writing this in seat 8D on the Ryanair flight from Béziers to Shannon and it’s extremely uncomfortable. My flight in sardine class has cost roughly €250 round trip. I could do this 18 times for the cost of a single one-way flight in a Dassault Falcon. But my bottom is protesting.

A stonking rich surgeon friend in London called me the other day and wanted me to chip in £500,000 for 10 per cent of a Pilatus PC-12, a sweet Swiss turboprop ideal for European peregrinations.  I’m thinking about it. Fly first class or your children will, seems the apposite rule here.  Would I regret this exorbitant expenditure on my death bed? I’m not convinced it’s as insane as it sounds. And even better if it annoys the likes of Just Stop Oil.