Some 15 - 20 years ago in the UK, there was a fashion for Customer Charters guaranteeing - or at least stating - standards of service. Train operators, for example, had to say that no more than x% of trains should run late and if they ran more than a specified time late, passengers could apply for compensation. All of this subsequently mutated into European Union passengers rights and obligations legislation.

One immediate response on the part of train operators was to add recovery time to their timetables. There always had been some, for understandable operating reasons. Building a complex timetable where 100% performance is expected day in, day out is just not realistic, so an allowance of 3 - 5 minutes was routinely put into the schedules of long distance trains.

But the new recovery time was put in to make it easier to meet Charter standards. It was put in between the last two stops, so that trains would find it easier to arrive at their final destinations on time. So the time in the timetable for trains to run between these two stops in one direction was rather larger than in the other - people would talk about timings "in the Charter direction". And this led to the odd headline in newspapers keen, as always, to knock railways.

But the practice is not unique to rail.

If you look in the timetable for London - Paris flights, you'll see they are scheduled to take an hour and ten minutes. As you reach cruise altitude, the captain welcomes you to this 40 minute flight. That's 30 minutes recovery time on a 70 minute flight! Wow!

Going to Lisbon recently, I was a bit surprised to see how long the flights took - 2 hours 40 minutes out, and ten minutes longer coming back. Going out, actual flying time - take-off to touch down - was exactly 2 hours. Chocks off to chocks on was just under 20 minutes longer. Coming back, the captain gave our flying time as 2 hours 10 minutes: it was actually about 5 minutes more, with a push-back to chocks on time of a few minutes over two and a half hours. Again, 40 minutes recovery time on a flight scheduled to take 170 minutes. That's just under 25% - that's some padding!

Clearly, sometimes it will be necessary - indeed, sometimes more will be necessary. When it isn't, you are allowing more time for a journey than it actually needs - indeed, the practice of padding might actually affect connections, again making your journey longer than it needs to be.

Is there any answer to this - apart from trying to make the aviation system more efficient?