Open Jaw: Your views on the polar plane route "Airlines cleared to use Santa's short-cut": on Christmas Eve, The Independent revealed new rules that open up the world to fuel-efficient twin-jets, promising faster, cleaner and cheaper flights. Despite the new and less restrictive regulations, I doubt the travelling public will have an appetite for being cooped up aboard an "aluminium tube" for the solid 18 hours it would take to fly from London to Fiji. Airbus and Boeing have offered the world's airlines ultra long-haul aeroplanes for some years now. The A340-500, unhindered by restrictions because of its four-engined specification, and easily capable of an 18-hour, non-stop stride, was a poor seller right up to its end of production this year. Human endurance limitations and thin economic benefits for such exotic routes are unlikely to result in Sir Richard Branson's Dreamliners going pole-vaulting anytime soon. Adam Sykes I note your travel correspondent, Simon Calder, was able to trumpet Virgin's delight at the latest aero-environmental breakthrough. So certain was he that this was good news for the planet, that he didn't feel the need to gain the endorsement of the environmental NGOs - only Balpa, Boeing and Sir Richard himself. Enough said. I'm sure Friends of the Earth and WWF would have been eager to lend their support for the idea of flying over the Arctic to save fuel. A by-product of such a move might be to enable trippers en route to their beach holidays in Fiji to see polar bears jumping from melting iceberg to melting iceberg while, at the same time, leaving behind vapour trails to ensure that their fast-disappearing homes become that bit warmer. John Webb Sir Richard Branson looked forward to new sightseeing opportunities: "Apart from the stunning destinations on arrival, the Arctic scenery will be just amazing on the way." Except the cabin crew will come around after the meal service and close all the window blinds. On the 787 it's done by the purser flicking a switch, so they are impossible to see through. Robin Peacock There is going to have to be some Arctic survival kit carried in the cabin. Like it or not, emergency diversion to aerodromes where temperatures are dangerously low will require protection for Hawaiian shirt-wearing holidaymakers. All very well making a safe landing, but then consideration would need to be taken before deplaning passengers into life-threatening temperatures between the aircraft and the terminal. Likewise, a diversion caused by an aircraft decompression could cause cabin temperatures to drop to life-threatening levels. The same could happen on trans-Siberian air routes today during winter, whether on two- or four-engined aircraft. TheGarden On my office wall at home is a certificate given to my father by Air France to mark his trans-polar flight from Tokyo to Paris. This routed via Anchorage and, as well as crossing the North Pole, it also crossed the International Date Line. This was in 1962 (50 years ago!). No twin-engine options then, it was a Boeing 707. Mind you, I wouldn't fancy a flight that far on two engines. I am reminded of the legendary Captain O P Jones, senior pilot of BOAC. When asked why he insisted on flying in four-engined aeroplanes he is said to have replied that it was because there were no five-engined planes available. Mike Ingham, Lincoln