The Citation II is a twinjet aircraft of conventional aluminium construction. Its two Pratt & Whitney JT15D-4 turbofan engines enable a maximum operating altitude of more than 13 km (43,000 ft) and a maximum cruising speed of 710 km/h (385 KTAS) to be attained. The flight envelope allows a wide range of operations to be performed. On-board OEM equipment includes full glass proline 21 Electronic Flight Instrument System (EFIS), a Flight Management System (FMS) with a Global Positioning System (GPS) sensor and a Flight Director / Autopilot. The Citation features a 10.7 m3 pressurized cabin that may be accessed through a 1.3 m x 0.6 m door. It can accommodate a maximum of eight observers in addition to the two-pilot cockpit crew.
For aerospace research the aircraft features:
• a separate electrical system dedicated to powering on-board test equipment, isolated from the aircraft electrical system for added safety;
• an additional stand-alone 3000 psi hydraulic system for operating test equipment or research actuators;
• provisions on the fuselage for mounting an external pod, for example with instrumentation or a radar;
• numerous facilities in the cockpit and the cabin for accommodating test equipment;
• a multi-channel digital data acquisition and recording system that can handle a large number of parameters with high accuracy at a high sample rate, and datalink facilities if required;
• research fly-by-wire capability that allows rapid testing of FBW control laws and autopilot software without the need for software certification
• on-board Wi-Fi network that allows real-time wireless access to measurement data and aircraft data buses.
• a “roof rack” on top of the fuselage that can accommodate multiple antennas, as well as underwing panels configured for antenna installation;
• a programmable high-resolution LCD display panel mounted in front of the right-hand instrument panel.
The research possibilities are numerous, and not confined only to aerospace science. The aircraft can be used to carry sensors (e.g. atmospheric air quality measurements, highly accurate gravitational measurements), to test equipment(e.g. satellite equipment) or to do research on novel cockpit concepts (e.g. Tunnel in the sky, human machine interface). Even zero-g manoeuvres can be flown to test behaviour at weightless conditions (e.g. medical sciences, geosciences).