The US Navy has grounded 39 of its 161 Lockheed P-3C Orion maritime-patrol aircraft because of structural fatigue concerns. Ten of the aircraft deployed operationally are included among those grounded.

Affected aircraft "are beyond known structural limits on the lower section of the P-3", says Naval Air Systems Command, adding this is the third time since 2005 that the US Navy has grounded part of its Orion fleet because of structural concerns.

USN P-3C in Japan
                                                                                                       © US Navy

The grounding is the result of an ongoing fatigue-life analysis and inspection of the airframes. The US Navy expects it to take 18-24 months per aircraft to repair and return the affected Orions to service.

L-3 Communications is refurbishing the outer and centre wing sections on US Navy P-3s, but Navair says the affected area responsible for the latest grounded is not covered by any existing repair programme.

The US Navy plans to begin replacing its P-3Cs in 2013 with 108 Boeing P-8A Poseidon anti-submarine warfare aircraft, but the Orion is expected to remain in service until 2020.

Source: FlightGlobal.com