IF you just happen to be reading this while shoe-horned into an economy-class seat on a flight out of Hong Kong, we suggest you first check the sick bag. Now read on. It was Keeping Posted's onerous duty at the weekend to try out a special gourmet menu prepared for Swissair first-class passengers by Winfried Brugger, the Hilton's executive chef. Naturally, we had to fly first class to Zurich in order to do so. Devoted to duty as always, we were settling our frame in a hi-tech sleeper seat and sipping a glass of vintage champagne before the other passengers even got near the aircraft. Brugger, to his credit, opted for a glass of mineral water while he explained it all to us before his pampered guests arrived. 'Most of the work was done in the airline kitchen where I spent about four hours before coming on board,' he said. Once in the galley of the aircraft, Brugger's roasted centre cut of Scottish salmon with crispy skin required only four minutes, the pan-fried tenderloin of US beef with port wine sauce about eight minutes and the rack of New Zealand lamb with spicy mustard and thyme around 20 minutes. (Which was just as well since the two shapely stewardesses who had been seconded to assist Brugger in the galley appeared to be taking a lot of his attention.) And what of the Swissair passengers? Second helpings were much in demand and one regular - notorious for his bad temper, we were told - said to the Hilton chef that he'd never tasted such excellent food on board an aircraft. 'He even managed a smile,' said Brugger, 'but only a very, very faint one.' The airline, meanwhile, is already planning another treat for passengers out of Hong Kong. The name of the chef being mentioned the next time around is Stefan Herzog of Stanley's. Herzog will have the added attraction of being Swiss himself. Brugger - and now we can say it - is, of course, Austrian.