 | This article needs additional citations for verification .(December 2009) |
| Learjet 31 | |
|---|---|
 | |
| Learjet 31A | |
| Role | Business jet |
| Manufacturer | Learjet |
| First flight | May 11, 1987 |
| Introduction | October 1990 |
| Status | Active |
| Primary users | Private NASA |
| Produced | 1987-2003 |
| Number built | 246 [1] |
The Learjet 31 is an American built twin-engined, high speed business jet. Manufactured by Learjet, a subsidiary of Bombardier Aerospace, as the successor to the Learjet 29, it has a capacity of eight passengers and two crew.
The first flight of the LJ31 took place on 11 May 1987. The Learjet 31A variant was introduced in October 1990. This version featured increased cruising speed, a digital avionics system with EFIS supplied by AlliedSignal (today Honeywell) and an instrument panel layout change. The nose gear wheel is steered by a Steer by Wire system. The windshield could be heated electrically.
The Learjet 31ER with increased range was produced.
The first 31A serial number 31A-035 entered service 15 August 1991. The 200th 31A was delivered in October 2000. [1] The last 31A delivered, serial number 31A-242 was delivered on 1 October 2003.
By 2018, late 1990s to early 2000s Learjet 31As begin at $600,000. [2]
The Learjet Model 31 is, arguably, the ultimate realization of the original Learjet series dating back to the Model 23 of 1963. Essentially combining the fuselage and engines of the model 35/36 with the “Longhorn” wing of the 28, 29 and 55 models, results in performance which is equaled by few aircraft. Normal cruise altitudes range from 41,000 to 47,000 feet (12,500-14,900 m) and the aircraft's maximum cruise altitude of 51,000 feet (15,500 m) is a distinction shared by only a handful of civil aircraft. Improvements over earlier models, such as “Delta-Fins” and a “Ski-Locker” increased the utility and improved the performance of the model 31. The addition of Delta-Fins at the bottom of the empennage simplified the certification process of the aircraft by eliminating the need for a “stick pusher” stall avoidance device. Increased directional stability, as a result of the Delta-Fins, was also a welcome benefit. However, a small cabin with little baggage space and no galley, and relatively short range because the Learjet 35/36's tip tanks were eliminated in favor of the winglet-equipped Longhorn airfoil, led to only 38 Learjet 31s being built. [3]
The Learjet 31A was announced in 1990 as a replacement. The model 31A boasted numerous modifications, however the most notable changes would take place on the flight deck. Key modifications and updates to the model 31A cockpit and avionics include; a Bendix King (now Honeywell after the merger with Allied Signal) Electronic Flight Information System 50, with Universal 1M, 1B and 1C flight management system, a dual KFC 3100 two-axis autopilot and flight director with yaw damper, and dual Bendix King (Radios sold to Chelton Avionics when Allied Signal combined with Honeywell) VCS-40A com units, VN-411B Series III navigation receivers.
In the year 2000 the Learjet 31A was again revised. Takeoff and landing weights were increased. [4] The original design N2 digital electronic engine control (DEEC) was replaced with an N1 DEEC, [4] [5] and the thrust reversers became standard equipment. Another notable improvement is Honeywell's TFE731-2 to -2C engine upgrade. [3] The original R12 freon air conditioning system was replaced with an R134A system divided into two zones - cockpit and cabin. [5]
The extended range version of the Learjet 31A, has a range of 1911 nm (2199 miles or 3539 km). Overall the numerous enhancements have led to more than 200 Learjet 31s in service with private operators and governments worldwide. [3]
Pakistan 
United States 
Indonesia 
Data from Jane's All The World's Aircraft 1988–89 [7]
General characteristics
Performance
A business jet, private jet, or bizjet is a jet aircraft designed for transporting small groups of people, typically business executives and high-ranking associates. Business jets are generally designed for faster air travel and more personal comfort than commercial aircraft, and may be adapted for other roles, such as casualty evacuation or express parcel deliveries, and some are used by public bodies, government officials, VIPs, or even the armed forces.
The Cessna Citation X is an American business jet produced by Cessna and part of the Citation family. Announced at the October 1990 NBAA convention, the Model 750 made its maiden flight on December 21, 1993, received its type certification on June 3, 1996, and was first delivered in July 1996. The updated Citation X+ was offered from 2012 with a 14 in (360 mm) cabin stretch and upgraded systems. Keeping the Citation III fuselage cross section, it has a new 37° swept wing with an area of 527 ft² for a fast Mach 0.935 MMo and a 36,600 lb MTOW for a 3,460 nmi (6,408 km) range, a T-tail and two 7,034 lbf (31.29 kN) AE3007 turbofans. After 338 deliveries, production ended in 2018.
The Learjet 60 is a mid-size cabin, medium-range business jet aircraft manufactured by Bombardier Aerospace in Wichita, Kansas. Powered by two Pratt & Whitney Canada PW305A engines, it has a range of 2,405 nautical miles (4,454 km) with NBAA 100 nmi (190 km) reserves, ISA. In July 2012 Bombardier Aerospace announced a temporary "production pause" of the latest variant Learjet 60XR to begin in the fourth quarter of 2012.
The British Aerospace 125 is a twinjet mid-size business jet. Originally developed by de Havilland and initially designated as the DH.125 Jet Dragon, it entered production as the Hawker Siddeley HS.125, which was the designation used until 1977. Later on, more recent variants of the type were marketed as the Hawker 800.
The Hawker 800 is a mid-size twinjet corporate aircraft. It is a development of the British Aerospace 125, and was assembled by Hawker Beechcraft.
The British Aerospace Jetstream 41 is a turboprop-powered feederliner and regional airliner, designed by British Aerospace as a stretched version of the popular Jetstream 31. Intended to compete directly with 30-seat aircraft like the Embraer Brasilia, Dornier 328 and Saab 340, the new design eventually accommodated 29 passengers in a two-by-one arrangement like the Jetstream 31. Eastern Airways of the UK is the biggest operator of Jetstream 41s in the world, with 14 in the fleet.
The IAI Westwind is a business jet initially produced by Aero Commander as the 1121 Jet Commander. Powered by twin GE CJ610 turbojets, it first flew on January 27, 1963, and received its type certification on November 4, 1964, before the first delivery. The program was bought by Israel Aircraft Industries (IAI) in 1968, which stretched it slightly into the 1123 Westwind, and then re-engined it with Garrett TFE731 turbofans into the 1124 Westwind. The 16,800–23,500 lb (7.6–10.7 t) MTOW aircraft can carry up to 8 or 10 passengers, and 442 were produced until 1987.
The Hawker 400 is a light business jet. Initially designed and built by Mitsubishi, it has been further developed and updated by the Beech Aircraft Company, now part of Textron Aviation.
The Dassault Falcon 900, commonly abbreviated as the F900, is a French-built corporate trijet aircraft made by Dassault Aviation.
The Gulfstream G100, formerly known as the IAI Astra SPX, is an Israel Aerospace Industries-manufactured twin-engine business jet, that was produced for Gulfstream Aerospace. Deliveries began in 1986. The United States Navy employs the aircraft as the C-38A Courier. A later derivative known as the G150 was launched in 2002. Gulfstream announced the final sale of the G150 in September 2016 and the last delivery by mid-2017.
The Cessna Citation II are light corporate jets built by Cessna as part of the Citation family. Stretched from the Citation I, the Model 550 was announced in September 1976, first flew on January 31, 1977, and was certified in March 1978. The II/SP is a single pilot version, the improved S/II first flew on February 14, 1984 and the Citation Bravo, a stretched S/II with new avionics and more powerful P&WC PW530A turbofans, first flew on April 25, 1995. The United States Navy adopted a version of the S/II as the T-47A. Production ceased in 2006 after 1,184 of all variants were delivered.
The Learjet Model 35 and Model 36 are a series of American multi-role business jets and military transport aircraft manufactured by Learjet between 1973 and 1993. When used by the United States Air Force, they carry the designation C-21A. Learjet was acquired by Bombardier Aviation in 1990 and is now a subsidiary, so the aircraft is also known as the Bombardier Learjet 35.
The Learjet 45 (LJ45) aircraft is a mid-size business jet aircraft produced by the Learjet Division of Bombardier Aerospace.
The Learjet 40 (LJ40) is a light business jet produced by Bombardier Aerospace.
The Learjet 55 "Longhorn" is an American business jet manufactured by Learjet.
The Learjet 28 is an American eight-to-ten-seat, twin-engine, high-speed business jet, intended to be the successor to the Learjet 25. The Learjet 29 is identical except for the addition of a long-range fuel tank, resulting in the reduction of the capacity to six. Both were manufactured by Learjet and were marketed under the Longhorn name.
The Garrett TFE731 is a family of geared turbofan engines commonly used on business jet aircraft. Garrett AiResearch originally designed and built the engine, which due to mergers was later produced by AlliedSignal and now Honeywell Aerospace.
Honeywell Aerospace is a manufacturer of aircraft engines and avionics, as well as a producer of auxiliary power units (APUs) and other aviation products. Headquartered in Phoenix, Arizona, it is a division of the Honeywell International conglomerate. It generates approximately $10 billion in annual revenue from a 50/50 mix of commercial and defense contracts.
The Cessna Citation Sovereign is an American business jet developed by Cessna, part of the Cessna Citation family. Announced at the 1998 NBAA convention, the Model 680 made its maiden flight in February 2002, certification was awarded on June 2, 2004, and deliveries began in late September. The Citation Excel fuselage was stretched and joined with an all-new, larger wing and more powerful Pratt & Whitney Canada PW306C engines for increased maximum takeoff weight and a 3,200 nmi (5,900 km) range. The improved Sovereign+ was announced at the October 2012 NBAA for a first flight in April 2013 and deliveries in December, with added winglets and an improved flight deck and engines.
The Learjet 70/75 is a mid-sized business jet airplane manufactured by the Learjet division of Canadian aircraft manufacturer Bombardier Aerospace. With the end of production in 2022 it is the last Learjet model.
