Gulfstream IV

==Operational history==
[[File:NOAA Gulfstream IV (N49RF) and WP-3 Hurricane Hunter (N34RF).jpg|thumb|[[National Oceanic and Atmospheric Administration|NOAA]]'s GIV and [[Lockheed WP-3D Orion|WP-3]]]]

The [[National Oceanic and Atmospheric Administration]] (NOAA) operates a GIV-SP (N49RF) modified to fly [[scientist]]s and crew members at 45,000 feet around [[tropical cyclone]]s. The aircraft was modified to drop instruments called "[[dropsonde]]s" 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. They also predict [[wind shear]] that will either increase or decrease a hurricane's strength. The GIV-SP is suited for this mission since it is fast, and can fly long distances with ample cabin space for the crew and instruments.<ref name="noaa_givsp">"[http://www.aoc.noaa.gov/aircraft_g4.htm Gulfstream IV-SP (G-IV)] {{Webarchive|url=https://web.archive.org/web/20070218124547/http://www.aoc.noaa.gov/aircraft_g4.htm |date=2007-02-18 }}." [[National Oceanic and Atmospheric Administration]] web site.</ref>  In 2009, the NOAA GIV-SP was further modified by the addition of a side-scanning [[Doppler radar]] to the rear fuselage. This radar is used for storm cloud profiling.<ref>[http://www.airliners.net/photo/NOAA/Gulfstream-Aerospace-G-IV/1566075/L Picture of the Gulfstream Aerospace G-IV Gulfstream IV-SP aircraft] Retrieved 1 November 2011.</ref>

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.<ref name=G-IV_airliners.net>[http://www.airliners.net/aircraft-data/stats.main?id=238 "Gulfstream Aerospace G-IV"]. airliners.net</ref>  In 1990, Gulfstream [[CEO]] [[Allen Paulson]] and a Gulfstream flight crew set 35 international records for around-the-world flight in a GIV.<ref>{{cite web|last1=Lacy|first1=Clay|title=Clay Lacy on Allen Paulson|url=https://www.claylacy.com/clay-lacy-allen-paulson|publisher=Clay Lacy|access-date=19 August 2014}}</ref>