Tim Furniss/LONDON

A Titan IVB booster was successfully launched into low orbit from Vandenberg AFB, California, on 17 August, carrying a $1 billion National Reconnaissance Office (NRO) satellite, believed to be a Lacrosse Onyx radar reconnaissance spacecraft.

The launch was the ninth in the Lockheed Martin Titan IVB programme since the first flight in 1997. Two launches without upper stages have been made from Vandenberg, while four launches with Inertial Upper Stages have been made from Cape Canaveral, one of which failed. There have also been three Titan IVB Centaur launches, one of which failed.

The latest Titan IV is believed to have carried a Lacrosse due to the measurement of the 20m (65.5ft) long payload shroud encapsulating the satellite and the associated flight hardware.

A Lacrosse satellite is 12m long, 4.4m in diameter, weighs 14,515kg (6,590lbs) and features a synthetic aperture radar system having a phased array antenna a deployed diameter of about 20m. When deployed, the craft's solar panels have a span of 50m. The best resolution from a Lacrosse is about 1m, although most images are of 3m resolution. The satellites can be used to identify targets for closer study by KH-12-class digital imaging reconnaissance satellites.

The Lacrosse is the fourth such satellite to be launched. The first was launched on the Space Shuttle in 1988, the second on a Titan IVA in 1991 and the third on a IVB model in 1997, the latter replacing Lacrosse 1, which was de-orbited.

The orbital inclination of these satellites can be 97.69í, although the Shuttle payload could only reach 56.9í inclination due to launch azimuth constraints from the Kennedy Space Center, Florida. The latest launch appeared to place the Lacrosse 4 into a 70í inclination orbit.

Source: Flight International