Graham Warwick/WASHINGTON DC
Boeing has begun laboratory testing critical software for the Lockheed Martin-led F-22 Raptor. The Block 3.0 sensor-fusion software must fly in an F-22 before the end of the year for the fighter programme to receive production funding.
Testing began on schedule in late May, in Boeing's avionics integration laboratory. The Block 3.0 software is planned for release to Boeing's 757 flying testbed in August and delivery to Lockheed Martin in early November.
Flight testing in the F-22 is scheduled to begin in mid-November, ahead of a Defense Acquisition Board meeting planned for mid-December, to decide whether to approve low-rate initial production of the fighter.
Lockheed Martin and Boeing remain confident of meeting the deadline, but it will be a "challenge", says programme general manager Bob Rearden. A subset of the Block 3.0 software, called 3S, has been flying on the 757 since April, to reduce risk.
Block 3S comprises 1.35 million of the 1.7 million lines of code in 3.0, Rearden says, but lacks the sensor fusion capability. "It allows us to look at the sensors independently before we combine them," he adds. Block 3.0 will fuse data from the F-22's radar, communication/navigation/identification and electronic warfare systems.
The fourth F-22 will require modification before Block 3.0 flight testing can begin. Aircraft 4004 is to fly in late June/early July, and will then be grounded in October for installation of new cockpit displays before returning to flight in mid-November with Block 3.0 software installed. The new Kaiser displays "worked first time" in the cockpit integration laboratory, Rearden says.
The team is already developing the next block of software, 3.1, which will be installed in the F-22 at its initial operational capability (IOC) in 2005. This includes full sensor and navigation fusion, as well as secure communications and intra-flight datalink.
Definition is under way of a Block 4 software upgrade which will introduce the Joint Helmet-Mounted Cueing System and AIM-9X air-to-air missile. This could be installed by IOC, Rearden says. Work has also begun on a Block 5 upgrade which would expand the F-22's air-to-ground capability. This could be incorporated as early as 2006.
Source: Flight International
