There are plans to update the UK military's fleet of armed vehicles
Delays in defence projects have left front-line troops in Afghanistan serving with almost obsolete equipment, a cross-party committee of MPs says.
Twenty of the Ministry of Defence's biggest projects are a total of 40 years late, the Public Accounts Committee said in a critical report.
Bills rose by more than £200m over the past year making forecast costs £28bn.
Defence Equipment Minister Quentin Davies strongly denied the delays had led to gaps in frontline capability.
The delays have meant a 12% increase in the estimated total cost of the projects.
The committee's chairman, Edward Leigh MP, said there were serious consequences for troops fighting in Afghanistan.
'Same old failings'
"What lies behind this are the same old failings: including, at the start of projects, both a lack of realism and unjustified optimism about what can be achieved, at what cost and by when.
"Delays to projects have led to gaps in our present front-line capability.
"For example, the MoD [Ministry of Defence] has had to use in Afghanistan interim vehicles and kit approaching obsolescence."
Projects hit by the delays include the Terrier armoured vehicle and the Soothsayer electronic warfare system.
BBC Defence Correspondent Caroline Wyatt said one of the most seriously delayed projects is the A400M aircraft.
This is due to replace the ageing Hercules fleet, which the committee says is now under tremendous pressure in Afghanistan.