Boeing is to receive a U.S. Navy contract to conduct additional fatigue testing on the P-8A Poseidon to determine the effects on airframe life of carrying the Raytheon Advanced Aerial Sensor (AAS) long-range, high-resolution surveillance radar.

The AAS is a dual-sided, active, electronically scanned array radar with a 40-ft.-long antenna housed in a pod mounted on a trapeze under the forward fuselage. The radar is designed to be carried on P-8As fitted with structural provisions for the pod.

Under a $138 million effort running through fiscal 2017, Boeing will conduct an engineering analysis of the AAS on the Poseidon airframe. This will include evaluating different mixes of AAS surveillance and P-8A maritime-patrol mission profiles to identify an optimum mix for future operations, according to Navy documentation.

The analysis will identify fatigue-critical areas specific to the AAS mission and compare them with those for the basic maritime-patrol mission. The S-2 full-scale fatigue-test article at Boeing will conduct two complete AAS mission lifetimes and a third P-8A mission lifetime, followed by a residual-strength test and a tear-down analysis.

Raytheon was awarded a contract in July 2009 to develop the AAS, a modernized evolution of the once-classified APS-149 Littoral Surveillance Radar Sensor carried by a small number of Navy Lockheed P-3C Orions.

Boeing received a $277 million contract in February 2012 to modify the first development P-8A, aircraft T-1, for aerodynamic and structural tests of the AAS radar pod. These tests are to be completed by August 2016.

Last year it emerged that the P-8A static-test article, S-1, had been diverted briefly to help with tests of the AAS. This had delayed the start of live-fire tests using S-1, required to support the decision on full-rate production of the P-8A.

An initial operational capability date for the AAS has not been revealed, but Boeing and Navy briefings have suggested it is likely to follow the scheduled 2016 fielding for the Increment 2 upgrade for the Poseidon.