The US Navy has completed the first of two operational test events on the Northrop Grumman MQ-4C Triton that could prompt a rethink of procurement quantities.

The operational assessment involved analysing sensor and aircraft performance over about 60 flight hours, Northrop says.

The tests evaluated the MQ-4C’s key sensors – an active electronically scanned array radar, an electro-optic/infrared camera and a hydrocarbon detector – over different altitudes and ranges, analysing the “system’s ability [to] classify targets and [disseminate] critical data”, Northrop says.

The navy is still analysing the results and a favourable review could clear the way for awarding the first low-rate initial production contract to Northrop in the second quarter.

The navy decided to launch low-rate initial production a year ahead of the next major operational test event.

The initial operational test and evaluate phase is scheduled to begin in fiscal year 2017, forming a 'graduation exercise' for the unmanned adjunct of the Boeing P-8A Poseidon maritime patrol aircraft.

MQ-4C Triton debut - US Navy

US Navy

In the navy’s original concept, the MQ-4C will provide broad area surveillance over five orbits encircling the globe. As the unmanned aircraft identifies targets, it will be able to cue the manned P-8A to go in for a closer look or deploy weapons.

That strategy led to the navy’s decision to buy 70 MQ-4Cs, including two aircraft reserved for flight test. Four aircraft are needed to support a continuous surveillance orbit at each of the five sites, leading to a fleet requirement of 20 aircraft. Another 48 aircraft were added to the procurement to replace attrition losses.

The attrition number was driven by a navy estimate predicting four aircraft losses per 100,000 flight hours.

That estimate has drawn scrutiny from the Department of Defense’s inspector general. In an audit released in September, the inspector general urged the navy to review the attrition requirement after the results of the operational assessment and the initial operational test and evaluation periods are available.