A Ministry of Defence review has found that soldiers are going into combat zones, such as Afghanistan, without sufficient training on vital communications systems.
It says the failure of some communications equipment, which often takes a year to fix, is compounding a shortage of gear to train with.
Routine training in New Zealand is affected, so the skill levels of personnel is lower than desirable when they are deployed overseas.
It also says the repair of the equipment bought from the US military can be slow. Much of it is returned to the United States for repair and the turnaround time can be up to 12 months.