The Portuguese Air Force has received the first of five upgraded P-3C Orion aircraft to replace its six aging P-3P aircraft.

Lockheed Martin Tactical Systems carried out the first two upgrades under a €99m ($137m) contract awarded by the MoD’s procurement agency (DGAED) in January 2008.

The remaining three aircraft are being upgraded by the Portuguese General Offices of Aeronautical Material, following which all five P-3C aircraft will be delivered to the air force by 2012.

The air force purchased the five P-3C Orion aircraft from the Royal Netherlands Navy in February 2005 for €200m ($276m).

Only one of the new P-3Cs is expected to enter air force service in March 2011, according to