Defence technology group QinetiQ has warned that the seasonally stronger second half will not happen this year due to a delay in orders from governments in both Britain and the US.Nothing's changed in the seven weeks since the company's November update when it reported 'short-term uncertainties in specific areas'.'The board now believes that the normal trading pattern of a seasonally stronger second half performance will not occur in the current financial year,' it said Friday. 'As a result, the group's performance in the second half is expected to be broadly similar to that of the first half.'Orders with the Americans for survivability products and Unmanned Ground Vehicles earmarked for Afghanistan have been pending throughout the year, and are now not expected before the financial year-end.Similar problems are holding back the UK division.Separately, chairman Sir John Chisholm has confirmed he'll retire on 28 February, handing the reigns to ex-IBM man Mark Elliott, who joined the board last May in preparation.The move will complete a new line-up at the top after chief executive Graham Love was replaced by the former chief of banknote printer De La Rue Leo Quinn late last year.