shifts. the faa is considering scheduling naps of 20 to 30 minutes for controllers after studies show those who nap were more alert during working hours. a week after the s&p fired a warning shot to the u.s. about its debt the international monetary fund has chimed in with a startling prediction about america's coming place on the global food chain. for details we get up in your business this morning, cnbc steve sedgwick live just up the street here in london. nice to be on the same continent for once. >> yeah, absolutely. well, i mean, this is a startling story coming from the imf by one measure, called purchase power parity, the u.s. will be a smaller economy than chinese economy in 20 16. u.s. economy will grow to $18.8 trillion but the chinese economy will grow from present $11.2 to $19 trillion. the imfes by another measure, market exchange rates, the u.s.