This Airborne Early Warning and Control variant of the P-3 was nicknamed Sentinel. Eight P-3Bs were converted into AEW&C aircraft, but although the Orion is globally succesful, this variant was never exported. The P-3 AEWs are used by US Customs and Border Protection's Air and Marine Operations for drug interdiction and homeland security missions. This N91LC (BuNo 155299) became N145CS with the CBP.

This Airborne Early Warning and Control variant of the P-3 was nicknamed Sentinel. Eight P-3Bs were converted into AEW&C aircraft, but although the Orion is globally succesful, this variant was never exported. The P-3 AEWs are used by US Customs and Border Protection's Air and Marine Operations for drug interdiction and homeland security missions. This N91LC (BuNo 155299) became N145CS with the CBP.