Shares in Redhall fell after the niche engineer said trading has been slower than anticipated partly due to bad weather and announced that its chief executive is stepping down.The company, which provides services for the defence and energy sectors, said: "Trading in the first quarter of the current financial year has been slower than anticipated in part due to the weather affecting progress on several major contracts."It added that trading for the rest of the year should be in line with previous expectations.It said that chief executive Simon Foster is stepping down for 'family reasons.' His duties will be taken over by chairman David Jackson while a replacement is sought.Redhall said that its contract pipeline remains strong.