Seven Boeing Sentry E3D aircraft have been taken out of service as a precautionary measure after the fault was discovered on a routine inspection.
The planes, based at RAF Waddington in Lincolnshire, provide early warning and fighter control systems.
The MoD said there would be no loss of cover as other aircraft were available. A spokeswoman said: “A routine inspection on an E3D aircraft at RAF Waddington has revealed a technical issue with one of the in-service aircraft.
“Routine E3D operations have been temporarily suspended pending further engineering investigation. There is no loss of operational capability.”
The spokeswoman stressed that the Sentry is one of a range of aircraft capable of conducting surveillance, and other options – including five Sentinel R1 aircraft – are being utilised.
Earlier this year, Defence Secretary Phillip Hammond flew onboard one of the fleet as the RAF practised security cover ahead of the Olympics.
Sentry aircraft were also used during operations in Libya in the battle to help depose Colonel Muammar al-Gaddafi.