Two prototypes were initially constructed using Bristol Siddeley Orpheus turbojets; one of these simple was experimentally re-engined with some four Pratt & Whitney JT12 in 1959, implying a later collection of the JT12 for production aircraft. The initial of those prototypes flew in the mid 1960's.
The JetStar was the initial business jet to enter service when the initial civil configured one was delivered in early 1961. Meanwhile the JetStar entered service with the USAF in 1962 while the C140 naval calibration aircraft and the VC140 VIP transport in late 1961.
Besides its fairly typical business jet layout, the JetStar is distinguishable from other small jets by its four engines, mounted on a corner of the fuselage, and Jetstar the fuel tanks fixed to the wings. It includes a cruciform tail and a thirty degree swept wing, which features large fuel tanks at about half-span. The horizontal stabilizer is mounted at the the top of vertical stabilizer. A rate brake is situated on the underside of the fuselage to greatly help slow the aircraft down for landing, and the trim is given by pivoting the entire vertical stabilizer, which is considered a strange characteristic by experienced aircraft designers.
The JetStar is recognized as a relatively heavy aircraft for its class. Weighting 25,250 lb when empty and having a max takeoff weight of 44,500 lb, it includes a maximum cruising speed of 0.8 Mach at 21,000 feet, and a variety of about 2,500 miles with a 3,500 lb payload.
It
has a team of two pilots and the cabin offers seating for up to ten passengers. Along the fuselage is 60 ft 5 in, with a 54 ft 5 in wingspan and a height of 20 ft 5 in. The aircraft includes a service ceiling of 43,000 ft.
The subsequent JetStar II differs from the earlier aircraft primarily in its four Garrett TFE731 turbofans making use of their significantly improved fuel consumption, causing substantial improvements in operating costs, range and lower noise levels, while more power allows an increased maximum takeoff weight.
This version is generally similar, with a number of detail changes. The cockpit area has some modifications, larger engines, and the fuel tanks are larger and sit making use of their upper surfaces flush with the wing, as opposed to being devoted to it. The initial of those flew on August 18, 1976, and has remained in production until 1979.
