If Britain falls off he metaphorical cliff edge with no Brexit deal a little under 18 months from now it is theoretically possible all flights between the UK and EU cousin tries will be grounded. That's not me being gloomy - it's the Chancellor, Philip Hammond. He should be sacked for his pessimism, says Lord Lawson. Will flights really stop? Unlikely in the extreme. But don't shoot the messenger. Theoretically they might. We have a single skies deal with Brussels that deadlock would invalidate. Theoretically the UK would need to negotiate bilateral civil aviation agreements with each of the 27 other member states. Even if you ignore the likelihood that we don't have enough skilled negotiators that would take months, probably years. But while Brexit poses other threats to flights it's obviously unthinkable that everything would suddenly grind to a halt. It follows that the "no deal" hard Brexit proponents argue is better than a bad deal is almost certainly an impossibility. I'm referring only to passenger aviation here. The same story could be replicated in other industries. There will have to be an accommodation of some kind with Brussels if flights are to continue, even if it that deal is incomplete and time limited. Even a limited transitional deal would need to be flexible. And during that time span it would clearly be difficult if not impossible to launch new - and perhaps badly needed - services. It's time the Government emerged from the rabbit hole - to find Michel O'Leary waiting with a new medicine bottle, this time labelled "Reality mixture - drink me!"