The Learjet 31 is an American built twin-engined, high speed
business jet
A business jet, private jet, or bizjet is a jet aircraft designed for transporting small groups of people. Business jets may be adapted for other roles, such as the evacuation of casualties or express parcel deliveries, and some are used by pu ...
. Manufactured by
Learjet, a subsidiary of
Bombardier Aerospace
Bombardier Aviation is a division of Bombardier Inc. It is headquartered in Dorval, Quebec, Canada. Its most popular aircraft included the Dash 8 Series 400, CRJ100/200/440, and CRJ700/900/1000 lines of regional airliners, and the newer CS ...
, as the successor to the
Learjet 29, it has a capacity of eight passengers and two crew.
Design and development
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.
The last 31A delivered, serial number 31A-242 was delivered 1 October 2003.
By 2018, late 1990s to early 2000s Learjet 31As begin at $600,000.
Variants
Learjet 31
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. Addition of Delta-Fins at the bottom of the
empennage
The empennage ( or ), also known as the tail or tail assembly, is a structure at the rear of an aircraft that provides stability during flight, in a way similar to the feathers on an arrow.Crane, Dale: ''Dictionary of Aeronautical Terms, third e ...
simplified the certification process of the aircraft by eliminating the need for a “
stick pusher”
stall avoidance device. Increased
directional stability
Directional stability is stability of a moving body or vehicle about an axis which is perpendicular to its direction of motion. Stability of a vehicle concerns itself with the tendency of a vehicle to return to its original direction in relation ...
, 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.
Learjet 31A
![Government of Balochistan Learjet 31A Asuspine-1](https://upload.wikimedia.org/wikipedia/commons/a/a6/Government_of_Balochistan_Learjet_31A_Asuspine-1.jpg)
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
Flight controllers are personnel who aid space flight by working in such Mission Control Centers as NASA's Mission Control Center or ESA's European Space Operations Centre. Flight controllers work at computer consoles and use telemetry to mon ...
with
yaw damper
A yaw damper (sometimes referred to as a stability augmentation system) is a system used to reduce (or damp) the undesirable tendencies of an aircraft to oscillate in a repetitive rolling and yawing motion, a phenomenon known as the Dutch roll. ...
, 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.
[Learjet 31A Type Certificate Data Sheet] The original design N
2 digital electronic engine control (DEEC) was replaced with an N
1 DEEC,
[Learjet 31A Pilot's Manual] and the thrust reversers became standard equipment. Another notable improvement is Honeywell's TFE731-2 to -2C engine upgrade.
The original R12 freon air conditioning system was replaced with an R134A system divided into two zones - cockpit and cabin.
Learjet 31A/ER
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.
Operators
;
*
Government of Balochistan, Pakistan
The Government of Balochistan ( ur, ) is the provincial government of the largest province of Balochistan, Pakistan in Quetta. The head of the province is the Governor, who is nominated by the President of Pakistan. The chief executive of the G ...
;
*
NASA
The National Aeronautics and Space Administration (NASA ) is an independent agencies of the United States government, independent agency of the US federal government responsible for the civil List of government space agencies, space program ...
;
*
Ministry of Transportation
A ministry of transport or transportation is a ministry responsible for transportation within a country. It usually is administered by the ''minister for transport''. The term is also sometimes applied to the departments or other government ag ...
;
*
Vinci Aviation
;
*
Panaviatic
Specifications (Learjet 31)
References
;Notes
;Bibliography
*
Taylor, John W. R. ''Jane's All The World's Aircraft 1988–89''. Coulsdon, UK:Jane's Defence Data, 1988. .
{{Learjet
31
1980s United States business aircraft
Twinjets
Low-wing aircraft
T-tail aircraft
Aircraft first flown in 1987