132 flights from Heathrow have been cancelled because of fog, and a weather warning for dense fog has been issued for Yorkshire and Humberside, the East and West Midlands, the East of England and the South East. That will probably mean further cancelled flights and severe disruption. I'm no aviation expert, apart from having flown as a passenger countless times, but I would have thought that in the 21st century,with all the technology at our disposal we could manage to come up with systems that would enable aircraft to take off and land without the people on the flight deck having to see the ground. Over sixty years ago RAF aircraft were able to take off and land in fog, thanks to a system known as FIDO. The idea was to burn petrol along both sides of the runway, thus raising the air temperature,which cleared the fog from the runway. I know it took a horrifying amount of fuel to do this, and I'm not suggesting anything like that. Nowadays we should surely be able to leave the fog where it is and get the aircraft onto and off the ground through it, or am I suggesting the impossible?