SkyCruiser, the UK AIP states that all aircraft are to maintain a minimum climb rate of 500fpm. If the pilot is unable to comply with this, he should let ATC know beforehand. I guess this means you tell the tower when you get start clearance. To be perfectly honest, it doesn`t make a terrific amount of difference to us ATCOs. We all like a good laugh in fact, oh will we ever have such amusement as when the Caledonian (RIP) ten-elevens used to climb out at 240fpm but `We can wind it up to 360fpm if you want, Sir`! Did they sit at Gatwick doing their checks to see if they would be able to clear the Alps??!! All the same, we all loved `em and we all miss `em. Cheers, BB.