The US Navy (USN) is expected to release Common Support Aircraft (CSA) definition studies in early 1998. It is keen to bring forward the aircraft's initial operational capability (IOC) to between 2005 and 2008.

The USN has a requirement for some 250 CSA aircraft, earmarked to replace: the Lockheed Martin S-3B Viking, ES-3A Shadow, Northrop Grumman E-2C Hawkeye; and C-2 Greyhound. Pulling forward the IOC is intended to reduce the costs associated with expensive E-2 and S-3 life-extension programmes. Accelerating CSA development is primarily a budget issue.

USN officials say that the CSA's mission-need statement will be submitted for action in early fiscal year 1998, with a Milestone Zero go-ahead for two years' worth of concept exploration due later that fiscal year. The product-development and risk-reduction phase would last for two to four years.

Boeing, Lockheed Martin and Northrop Grumman are all expected to bid for the definition studies. At least two study contracts are expected to be awarded.

A prime contractor would then enter engineering and manufacturing development (EMD) which is set to run through FY2010. Production would follow and continue for more than a dozen years at an annual rate of 12 to 24 aircraft.

It is still unclear whether the CSA will be a conventional take-off-and-landing, short-take-off-and-landing, or short-take-off-vertical-landing aircraft. The choice of powerplant type - whether turbofan or turboprop - has also yet to be decided.

A single CSA airframe will be specially configured for various missions, including carrier on-board delivery (COD), anti-submarine warfare, airborne early warning (AEW) and signals intelligence. The COD aircraft, for example, would carry as many as 26 people and have a maximum range of 4,079km (2,200nm). The Hawkeye 2005, the next-generation avionics suite for the E-2C, is the baseline AEW system for CSA.

Source: Flight International