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Kansas Trotter

From that distant day, 7th October 1963, when the first light administrative and business Learjet 23 took to the air, nearly 50 years past. During this period ten more models were added to Learjet family; they developed the ideas integrated into the firstborn design. Learjet 60, the heaviest and the most comfortable representative of the glorious family became the result of designers’ creative efforts.

Comfort or Speed?

At the beginning of the 1960-ties at the dawn of business-jet era, the most venerable and honorable analytics forecast quite modest number of copies for the new jet class. It was assumed that a personal business jet would be just a toy for kinky money-bags and it would hardly bring worldwide glory and multimillion profits to its creators. Oh, skeptics, if they only knew what the genius is capable of at the moment of afflation.

A talented American jet designer William (Bill) Lear was not less talented (or maybe even he was even more talented) businessman; he resolved upon anticipating the demand of which other entrepreneurs were still unconscious at that time. A blessing in disguise: Swiss Government rejected FFA P-16 bomber-fighter designed by Lear and this event inspired the designer to present the jet to the world in a new role – of a light passenger jet for private service.

Learjet 23 (initially - SAAC Lear Jet 23) designed in 1963 proved to be a really the smallest and the cheapest jet liner in the world: its tiny tight passenger cabin housed maximum 5-7 passengers; only one pilot could fly the jet. The original high-speed wing which Learjet 23 had inherited from P-16 secured the project success. The wing was straight but its profile was unusually thin for that time and it had advanced take-off and landing devices. Only fuselage was intrinsically new; two engines were placed in the tail (analogous to French Caravelle); pilot’s cockpit glazing was unusual; this made the civil jet look like a fighter. It was a perfect marketing trick, we should acknowledge this. It took some time for potential consumers to appreciate such a novel product; but when they tired it they lined up in a queue. Just as far-seeing Bill Lear presumed, a post-war businessman was ready to trade comfort for speed.

It was no coincidence that we started the article about Learjet 60 from the history of Learjet 23 creation. This jet for the first time had embodied the rational minimalism principle in private jet aviation and thus set standards not only for many business-jets of other manufacturers but first of all for Learjet family. However we are not talking of minimalism alone.

Combatant Temper

Military genealogy and rational adequacy principle immanent first of all to military aircraft were integrated into the basis of Learjet business-jet family technical image. Developing gradually Learjet of course moved closer and closer to classic standards but many features were carried over from one model to another and finally our hero Learjet 60 inherited them. So, what is so very unusual about this jet?

Learjet 60 which for the first time took off on the 13th June 1991 was meant to replace Learjet 55 being the first jet of the family with enhanced diameter fuselage. In the past Bill Lear parried critics of tight Learjet 23 passenger cabin saying: «You cannot stand in Cadillac! » In other words, you either get a jet with really limited comfort but high-speed and affordable in price or look for other offers and get ready to overpay. But by the beginning of the 1970-ties situation started changing; in order to meet growth of demand for more comfortable business-jets Gates Learjet Co. resolved to modernize fuselage radically. Surely Learjet 55 became somewhat heavier and stayed behind its fellow jets as regards flying and technical characteristics; sooner or later those characteristics should be improved to achieve the adequate Lear level. It was done in Learjet 60 design indeed. Learjet is speed. This was the initial idea, and they strived not to recede from it. Taking into account the spirit of this Company slogan Learjet 60 was equipped with powerful and saving Pratt & Whitney engines instead of traditional Garrett ones. Thrust increase affected take-off and landing characteristics: dynamics of climbing became really similar to that in fighters; jet with allowable take-off weight climbed to 12 500 m altitude within 16-18 minutes and it performed climbing straightly without any “flats”. But landing approach speed increased, too; so engines were equipped with operational thrust reverse devices. As a result short take-off and landing jet was designed; it can land at airdromes with air-strips not beyond 1 km. Typical as regards its mass medium business-jet with take-off and landing characteristics equal to those for light jets impressed potential clients.

High flight speeds at all modes immanent to Learjet 60 were achieved not only by virtue of powerful engines but also thanks to wing profile and thus the whole jet aerodynamics. Needless to say it is not that slam winglet made for light fighting jet but it is its fit development. Learjet 60 the same as its ancestors has high wing unit load. Namely, its area is not big thus significant share of jet mass falls to each square meter. This wing helps increasing speed but it demands enhanced claims as regards stability and controllability, especially at low take-off and landing speeds. In this regards Learjet 60 wing is the most “polished” ones. It is not coincidence that it was covered by vertical flow fences and wing dogtooth extensions at the root.

Generally stability and controllability of Learjet family jets added some problems in the past; designers had to put much effort to settle them. High maneuverability always let these jets negotiate complicated paths of “inconvenient” airdromes and cut off corners in intensive traffic areas effectively. But as regards their stability Learjet jets have been and are considered to be “slippy”. This is due not to lack of stability but rather to lack of excessive stability such as, for example, Hawker family business-jets have. Flying Learjet 60 means to be professional in this job; an inexperienced pilot cannot employ all the remarkable capabilities of this “business-fighter”.

Passenger cabin dimensions do not give chance to consider it spacious: height is 1.73 m is not quite sufficient for a person to stand upright. But still it is more than 1.5 m height as in other Learjet models. It is rational compromise for those who understand because long ago it was noticed that absolute majority of passengers are not inclined to walk along the cabin during the flight. Instead Learjet 60 flies without excessive noise and very smoothly, because jets with high wing unit load are less exposed to bumpy flight in turbulent atmosphere.

Tendency to free jets from unnecessary details was always the distinguishing feature of Learjet Company creative style, but when it joined Bombardier group, new top management requested to introduce some changes. For example, it was the «60th» which acquired one-spot centralized fuel feeding system which allows reducing jet flight preparation time. As to radio electronics and navigation equipment Learjet jets were never deprived, but in these aspects everything depends on modifications.

Three modifications of Learjet 60 are known: initial (Learjet 60) one, Special Edition Learjet 60 and Learjet 60XR. The main changes are as follows. In Special Edition modification passenger cabin interior was modified and some additional options such as audio system and satellite communication were added. But Learjet 60XR design underwent much more significant changes. New passenger cabin equipped following module principle became one cm wider and one cm higher; Air Show video system was introduced; LED lighting with sensor control, ports for personal notebooks with Internet access appeared; pilots got the most modern set of digital Pro Line 21 avionics made by Rockwell Collins at their disposal. Even a window was added into the lavatory in order to brighten up the life.

Typical buyers of Learjet 60 are practical people appreciating time and money. At the cost from $ 6 million up to $ 13.5 million this quite a comfortable and high-speed jet maintains relatively modest operational expenses; one hour of its flight costs $ 2000 and something and it can fly from Moscow all over Europe, to the Middle East and around Russia as far as to Irkutsk. It is not bad for the descendant of a light fighter.

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