In 2001 Gulfstream began work on an improved version of the GIV-SP, originally designated GIV-X. It was later renamed G450. The G450 is lengthened 1 ft (0.305 m) over the G400 and shares the forward fuselage and larger cockpit of the G550. Production of the G450 began in October 2004, replacing the G400. The G450 has better performance and comes with the PlaneView cockpit with four 14 in (355 mm) liquid crystal displays and a Head up display (HUD). The shorter range G350 version of the G450 was developed and received certification in 2004. In June 1987 a Gulfstream IV set 22 world records in its class in flying west around the world in 45 hr 25 min. The next year another GIV set 11 world records flying east around the world. In 1990, Gulfstream CEO Allen Paulson and a Gulfstream flight crew set 35 international records for around-the-world flight in a GIV. The National Oceanic and Atmospheric Administration (NOAA) operates a GIV-SP (N49RF) modified to fly scientists and crew members at 45, 000 feet around tropical cyclones. The aircraft was modified to drop instruments called "dropsondes" to measure windspeed, barometric pressure, humidity, and temperature as they fall to the surface of the ocean. By sampling the cyclone with these dropsondes over a 4, 000 mile track around the storm, the forecasters at NOAA's National Hurricane Center and Hurricane Research Division can better predict where the hurricane will be "steered" by the upper level winds.
