Northrop Grumman has delivered the first two of 14 upgraded RC-12X Guardrails to the US Army.

The army commissioned the structural and sensor upgrades to keep the electronic eavesdropping aircraft viable through 2025 following the cancellation of the Aerial Common Sensor programme in 2006.

Northrop says the Guardrail modernisation programme introduces "new payloads" to address new signal emissions rapidly emerging from both irregular and conventional targets.

One of the payloads is understood to include Northrop's airborne signals intelligence payload (ASIP), which is aimed at intercepting communications channels in the low-band of the spectrum.

The first two aircraft have been delivered, but the new capability is not scheduled to become operational until the second quarter, Northrop says.

The company is "eager to continue to work with the army to make the system operational as soon as possible", says Trip Carter, director for Northrop's airborne intelligence, surveillance and reconnaissance initiatives.

Earlier this week, Northrop also unveiled the multi-band synthetic aperture radar (MB SAR) payload, which the company plans to install on the army's King Air fleet. The RC-12 Guardrail is a sub-set of that fleet.

Meanwhile, the army is still waiting to launch a programme to eventually replace the existing RC-12 Guardrails.

In November, Boeing was awarded the contract to develop the enhanced medium altitude reconnaissance and surveillance systems (EMARSS), which is also based on the King Air 350ER.

However, three losing bidders filed protests with the Government Accountability Office, which has halted the EMARSS programme through at least late March.

The army launched the EMARSS acquisition process about three years after cancelling the Lockheed Martin ACS after the contractor miscalculated the size and weight of the sensor payload.

Source: Flight International