Three bidders have protested the US Army's $88 million contract for Boeing to deliver a new fleet of aircraft carrying multiple intelligence payloads.

The protests filed in late December with the US Government Accountability Office (GAO) freezes the acquisition of the enhanced medium altitude reconnaissance and surveillance system (EMARSS) at least through March.

Despite the contract dispute, the army hopes to accelerate the programme. EMARSS was among a handful of army programmes singled out for extra funding on 6 January by Secretary of Defense Robert Gates.

However, if the GAO sides with the losing bidders -- L-3 Communications, Lockheed Martin/Sierra Nevada and Northrop Grumman -- the army may need to repeat the year-long competition to win the EMARSS contract.

The $88 million deal awarded to Boeing on 30 November calls for the delivery of six Hawker Beechcraft King Air 350ERs equipped with an electro-optical/infrared sensor, a signals intelligence system and two onboard processing stations.

Follow-on contracts could raise the total fleet to 30 aircraft -- redesignated as MC-12s -- that will replace the RC-12 Guardrail fleet.

Boeing's victory in the EMARSS competition marks a strategic coup for the company, which plans to dramatically expand its presence in the market for signals intelligence aircraft.

But the contract award also disappointed the army's traditional signals intelligence suppliers. Northrop, for example, is the army's incumbent supplier for intelligence-gathering, fixed-wing aircraft. L-3, meanwhile, delivered a similar capability to the USAF with the MC-12 Liberty programme. Finally, Lockheed's partner Sierra Nevada delivered the original MARSS system to the US army, which transferred the aircraft to Iraqi forces.

Boeing, however, has been eying the intelligence market for several years. The comapny has unveiled plans to adapt the submarine-hunting P-8A Poseidon into an signals intelligence aircraft for the navy and air force. Last year, the company also acquired signals intelligence payload specialist Argon ST.