The Gates Learjet family and Bill Lear's designs

hesham

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From USA,

Learjet Model-26 :proposed Model-25 with TFE731 engines.
Learjet Model-40 :Lear Liner project.
Learjet Model-54 :enlarge Learjet with 10 passenger cabin using
Model 28/29 wing married to new fuselage and
powered by two Garrett TFE731-3-100B engines.
 
Learjet Model 26 became the Learjet 35/36 when they changed the designations to fit different engine types. The first prototype had the serial number NGL2601 as I remember and was eventually sold to P&WAC as a testbed for the JT15D-5 which Learjet was at one time considering for a lower-cost member of their "30 series" (as I remember, it was the original study for the Model 31). Somewhere I've got a picture of it flying with two JT15D-5s installed in Canadian civil experimental registration.

The Lear Liner was also numbered as the Model 28 at one time and would have been competitive with the Gulfstream II.

The Model 54 was one of the "tall-cabin" Learjets along with the Model 55 and Model 56. The difference being a tradeoff of interior volume against internal fuel. As it was, only the Model 55 was produced, though an extended range version of that was developed by converting the aft half of the aft external baggage compartment into an auziliary fuel tank. The location of the front end of this fuel tank was defined by the need to stay out of the burst zone from either engine for an uncontained rotor burst. I was rather involved in this effort back in 1982.
 
Here is a 3-view of the Lear Model 28
(from Flying Review 9/64)
 

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Jemiba said:
Here is a 3-view of the Lear Model 28
(from Flying Review 9/64)
Thank you! What was the proposed powerplant for the Lear Liner? It appears from the line drawing to be some sort of aft-fan powerplant.
 
"What was the proposed powerplant for the Lear Liner?"

The short note say : Two 4.200lbs GE CF-700-2B turbofans
 
Dear Jemiba,

I don't know the engines of Lear Liner,but I will search.
 
by the way,

the Gates Lear jet Twinjet helicopter project was called Model-112.

http://books.google.com.eg/books?id=rBksUk40jlEC&pg=PA200&dq=wing+forward-swept&hl=ar&ei=-_SATPjeJMiLOPubrKsO&sa=X&oi=book_result&ct=result&resnum=5&ved=0CDwQ6AEwBA#v=onepage&q&f=true
 

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From Flug-Revue 1964
 

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A beautiful document originally published in FLYING, September 1977.
 

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Dear Boys and Girls, here is a short article in French announcing the Lear Model 40 Lear Liner regional jet which would have been powered by the same Rolls-Royce Spey Junior engines as the Fokker F.28 Fellowship......

The article comes from the 1st November 1965 issue of Aviation Magazine International......

Terry (Caravellarella)
 

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Any idea why the Model-112 didn't make it to the prototype stage? (Google Books link doesn't seem to be working)
 
Grey Havoc said:
Any idea why the Model-112 didn't make it to the prototype stage? (Google Books link doesn't seem to be working)

Sorry Grey Havoc, I don't know why the Gates Model 112 Twinjet helicopter remained a "project". Here is an article in French that I've found......

The article comes from the 1st October 1969 issue of Aviation Magazine International......

Terry (Caravellarella)
 

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Has anybody ever heard of a Lear Astronics Q-20. I picked this up many years ago from an obscure source an I have assumed if may be a drone in the USAF Q series, but no ther info found so far.
 
Jos Heyman said:
Has anybody ever heard of a Lear Astronics Q-20. I picked this up many years ago from an obscure source an I have assumed if may be a drone in the USAF Q series, but no ther info found so far.

Highly unlikely if we consider the fact that the original Q- series was post-war and ended with the 1962 tri-service system at XQ-12, the Beech Jayhawk (there was also a Q-14 but it was just the former PQ-14 redesignated in 1948). After that, the drones or RPVs were given QM- designations in the main missile and unmanned list. So there is no way a Lear Q-20 could have found its way there either. As for today's new "Q-" system, introduced in 1994 with the General Atomics Predator, it has only just reached #19 with the AAI XMQ-19A Aerosonde in 2009... So you see, there is no room there either for your "Q-20", sorry... :-\
 
Stargazer2006 said:
Terry, you're da man!!! ;)

Well I've not been called that before; so thank you Stéphane ;D......

Here is another image of the Lear Model 40 Lear Liner regional jet project......

The image comes from the 1st August 1966 issue of Aviation Magazine International......

Terry (Caravellarella)
 

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Dear Boys and Girls, here is another article in French about the Lear Model 40 Lear Liner regional jet "project"......

The article comes from the 15th June 1966 issue of Aviation Magazine International......

Terry (Caravellarella)
 

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Dear Boys and Girls, here is a picture with a caption in French of the mock-up of the Gates Model 112 Twinjet helicopter project as exhibited at the NBAA in 1969......

The picture comes from the 15th November 1969 issue of Aviation Magazine International......

Terry (Caravellarella)
 

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Topic updated with Lear-related posts from a generic topic. Feel free to add!
 
Gates' Twinjet - the Corporate Ship that Never Left the Ground

The Gales Twinjet helicopter, a twin-turbine ship designed for corporate transportation and utility applications, was 10 years and one recession ahead of its time. Unveiled as a mock-up craft on September 11, 1969, at the Gates LearJet plant in Wichita, Kansas, the pioneering helicopter was to cruise at 180 mph and carry eight to twelve passengers.

The project gathered what some called the finest group of experts from throughout the helicopter industry, and drew upon the experience of engineers from Bell, Boeing Vertol, Hughes and Sikorsky. More than $4 million was spent on the project, with more than 100 full-time engineering personnel involved.

Preliminary structural details announced in 1969 were for an aircraft that would sell for between $400,000 and $450,000 that could be used for office-to-airport travel. Range would be 400 miles. It was to have a fuselage that would be both aerodynamic and make maximum use of cabin space. It would have a low empty weight and an optimized rotor configuration that would provide the best lift/drag ratio for high performance at a gross weight of 6,000 lbs.

The four-bladed main rotor's diameter was 40 feet, and the ship's overall length was 42 feet. Two 474-shp Garrett TSE turboshaft engines were to be mounted above the main cabin in stub wing fairings. The baggage compartment was to be 70 cubic feet.

Complete preliminary layouts of all systems had been accomplished, and master tooling and major production facilities were nearly operational when the project was dropped because of the 1970-71 recession. The Gates Twinjet had been scheduled to make its first flight in 1971, with FAA type certification to have been completed in 1972.

The model shown is a part of the Helicopter Foundation International (HFI) collection. It was constructed by Gates Aircraft and donated to HFJ. The scale model is available for viewing at HAl headquarters in Alexandria, Virginia.

Source: ROTOR, Spring 1997
 

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Even 45 years later, this helicopter design looks modern and very cool! B)


Source: Ein echter Geschäftshubschrauber: Die Gates Twinjet Helicopter - Interavia Germany, November 1969, pages 1784 and 1785
 

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Found in VertiFlite, December 1969, a color photo of the GTH mockup and a drawing
of the internal arrangement in the executive transport and in the air ambulance version:
 

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Nice! Thanks for these.

Can the "Re:" be removed in the topic's title? Thanks in advance... ;-)
 
https://www.facebook.com/photo.php?fbid=10205223323319584&set=o.34366349783&type=1&theater
https://www.facebook.com/photo.php?fbid=10205223323479588&set=o.34366349783&type=1&theater
 

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When I worked there, 1979-1982, I remember seeing a few drawings of a twin-turboprop pusher design. What particularly boggled my mind at the time was that the intended engines were some rather modified TPE331s. If memory serves me correctly, and this is looking back some 35+ years, it did look somewhat like the later Piaggio Avanti. I wish I'd taken more of an interest in this info then.
 
Lear Jet helicopter

AWST article
 

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Re: Lear Jet helicopter

My dear RAP,

we have it here;

https://www.secretprojects.co.uk/forum/index.php/topic,18024.msg103086.html#msg103086
 
Re: Lear Jet helicopter

My bad. Mods feel free to move or delete.

Topics merged
 
The Lear Liner Model 40 deserves additional comment. As already noted by elmayerle, this aircraft would have competed directly with the Gulfstream II as a bizjet, while also being pitched as a feederliner. Originally envisaged as a 28-seater (in airline layout) powered by two 8,750 lb-thrust Rolls-Royce Spey Juniors when first launched in 1965, the aircraft was subsequently upsized to a 40-seater (necessitating a 15 ft fuselage extension), powered by two 11,400 lb-thrust Rolls-Royce Spey 25s (Mk 511-14Ws).

The Model 40's first flight was targeted for the autumn of 1967, with certification and first deliveries to follow in spring 1968, Lear envisaging just under 500 sales over the subsequent decade. In the event, the cost of the Model 40's development, coupled with a fall in Learjet 23/24 sales, led to Lear Jet Corporation suffering a loss of $12 million in 1966 (compared to a profit of $54 million the year before), resulting in the company being sold to Gates Rubber Company in 1967. The Lear Liner did not survive the transaction, Gates preferring to focus on smaller models such as the Learjet 25.

Links:
Lear Liner sales to near 500 in decade (Aviation Week, November 1, 1965)
Lear Jet - Bill Lear's beauty from the Kansas cornfields (Flight, March 10, 1966)
A bigger Lear Liner (Flight, May 26, 1966)
Aero engines - Rolls-Royce (Flight, January 5, 1967)
Biz jets: technology and market structure in the corporate jet aircraft industry (Phillips, Phillips & Phillips, 1994)
Lear Jet: 50th anniversary milestone (Flying, July 6, 2016)
 

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Lear Liner pic
 

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And some more pics. The liner got extended after customer responses
 

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Found this in a 1969 copy of AHS Vertiflight Magazine.
 

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I have had a go at pulling together a Learjet designation list...

What's in a Name? - Lear Jet, Learjet, and Bill Lear Sr.'s Later Projects

At the corporate level, Learjet has been through a host of changes. Beginning as the Swiss American Aircraft Corporation (SAAC), [1] the name Lear Jet (or a hyphenated Lear-Jet) appeared with the move to Wichita, KS in 1962. In 1969, the one-word Learjet was adopted. That conjoined Learjet name has since lasted through multiple ownership and corporate name changes. [2]

Lear brand names tended to be re-applied and recycled. Names like Learstar (originally based on Lockheed 18 Lodestar donor aircraft) would later be reapplied to what eventually morphed into the Canadair Challenger - first as Lear Star (early 1976), then LearStar (later 1976). Bill Lear Sr. tended to use his corporations as private fiefdoms with porous boundaries. As as result, the Lear Jet would also be applied to a pet project - the Lear Jet Stereo 8 automotive player for his 8-track tapes. [3]

I will list Learjet designations first and then follow with a second list for the other projects I am aware of. Doubtless there are many more - any additions and corrections are most welcome.

Learjet Designation Numbering and Style

According to William P. Lear Jr., the original designation - SAAC 23 - indicated the 23rd iteration of a design process which took place over several years. [4] That number was retained for the first built model - the Lear-Jet 23. Each major design variation featured a designation one number higher until the unbuilt Model 26. AFAIK, there was no Model 27 and later numbering seems to have been at the whim of the marketing department - eg: Model 26 became the Model 35 (presumably for a numerical connection to the turbojet Model 25 it was to replace). That randomness increased when Bombardier too over - Bombardier's Learjet designations jump about and sometimes slot in between numbers assigned 40 years earlier.

I've tried to stick to manufacturer's style for designations ... more-or-less. Early on, the formal style was, for example, Model 23 but Lear-Jet 23 was used even in company literature. I have tried to avoid the commonly used 'Learjet 23' except when identifying typos. And, of course, all that changes with the 1969 branding name change.

I have used the 'Model xx' style throughout but it has become more and more common to use the 'Learjet xx' form.
Reporting codes are often inserted into discussions of Learjets. So, a Learjet 31 will be listed by its ICAO identifier (LR31, sometimes 'LR-31') or FAA type code (LJ31). I have ignored such codes as short-forms rather than being truly designation-related.

________________________________

[1] SAAC was initially in some form of production arrangement with Flug- und Fahrzeugwerke Altenrhein (FFA). However, it seems that William P. Lear Sr. was the sole owner of SAAC. At the time, Swiss labour costs were lower but work proceeded unsatisfactorily slowly in Switzerland for Lear (although that perception reflected the work force or regulations is unclear).

[2] Corporate identities were/are as follows: Swiss American Aviation Corporation (c.1959); Lear Jet Corporation (26 April); Lear Jet Industries Inc. (19 Sept 1966); Gates Learjet Corporation (02 Dec 1969, merger with Gates Aviation); Gates Learjet begins Aerospace Division (1984); Learjet Corporation (04 April 1988, following 09 Sept 1987 acquisition by Integrated Acquisition, Inc.); Learjet Corporation (as a division of Bombardier Inc. after 29 June 1990 purchase).

Source: https://web.archive.org/web/20061231131658/http://www.wingsoverkansas.com/history/article.asp?id=199

[3] Other Lear Industries brandings were distinct - eg: the LearAvian portable radio for general aviation use.

[4] It's not clear whether those were 23 distinct Lear designs, variations, or included forays such as discussing evolutions of the MS-861 Paris with Morane-Saulnier.

Source: AIN, Learjets and Swiss fighters, letter by William P. Lear Jr., 31 Jan. 2007
-- https://www.ainonline.com/aviation-...l-news/2007-01-31/learjets-and-swiss-fighters
 
Swiss American Aviation Corporation (SAAC) based in Geneva, Switzerland (later Wichita, Kan.

Swiss-American Aircraft Corporation

SAAC 23 - (Project) Execujet, based upon FFA P-16*
- SAAC 23: Twin-turbojet bizjet, cruciform tailplane
- SAAC 23: 2 x 1,920 lbf Continental 352,** span 10.84 m
-- * Rather loosely, according to William P. Lear Jr.
-- ** Most refs use J69, Turbomeca Marboré devel.
_____________________________________________________

Learjet Aircraft Designations

Lear-Jet 23 - 1963 twin-turbojet executive jet, x 101
- Model 23 : Rebranded SAAC-23 for Lear-Jet, Wihcita
- Model 23 : (Project) orig. Lear-Jet, cruciform tail
- Model 23 : 1963 prototye/production version, T-tail
- Model 23 : 2 x 2,850 lbf GE CJ610-1s, span 10.84 m
- Model 23A: 1965, 2 x 2,850 lbf GE CJ610-4 turbojets

Lear-Jet 24 - 1966 twin-turbojet executive jet, x 259
- Model 24 : Intended successor model to Lear-Jet 23
- Model 24A: 2 x 2,850 lbf GE CJ610-4 turbojets, x 81
- Model 24B: 1969, all-weather variant, +500 lb TOW
- Model 24B-A: Reduced weight 'B variant, MTOW
- Model 24B: 2 x 2,950 lbf GE CJ610-6 turbojets, x 49
- Model 24C: (Project) 1969 lightweight vers. of '24B
-- Model 24C: Fuselage tank removed, canc'd Dec. 1970
- Model 24D: 1970 prod. vers., aerodynamic impr., x 99
-- 24D s/n 24-218 used to flight test Longhorn wing
- Model 24D-A: Reduced weight 'D variant, MTOW 5,669 kg
- Model 24E/Model 24F: 2 x 2,950 lbf GE CJ610-8s, x 29
- Model 24E: 1976, Century III, wing aerodynamic impr.
- Model 24F: 1976, Century III, longer range variant
- Model 24F-A: Reduced weight 'F variant, MTOW
-- Revised tip tanks, tail bullet removed

Lear-Jet 25 - 1967 stretched-fuselage devel., x 369
- Model 25 : 1.27 m stretch accommodated + 3 pax
- Model 25A: 2 x 2,950 lbf GE CJ610-6, span 10.85 m
- Model 25B: 1970, aerodynamic improvements
- Model 25BGF: 1971 TFE 731 turbofan testbed conv.
-- N26GL known, unofficially, as 'Model 26' (qv)
- Model 25C: 1970, longer range, increased fuel
- Model 25D: 1976, long-range vers., GE CJ610-6
- Model 25D: 1976, Century III wing, GE CJ610-8A
-- aka Learjet Century III 25D, aka 'LR-25D'
- Spirit Wing re-engining prototype s/n 25D-316
-- GE CJ610 engines replaced with Williams FJ44s
- Model 25E: 1976, Century III wing, GE CJ610-8A
- Model 25F: 1976, long-range (2,152 nm) 8-seat
-- Revised tip tanks, tail bullet removed
- Model 25G: 1980, Century III, GE CJ610-8A
- Learjet 25TF: Robertson Aircraft upgrade mod.
-- Winglets on tip tanks, JT15Ds replace CJ610s

Lear-Jet 26 - (Project) 196? turbofan-engined Model 25
- Model 26 : 2 x Garrett AIResearch TFE731 turbofans
-- With mods, later became Learjet Models 35/36 (qv)
- Model 26: Unofficial desig. for N26GL testbed
- Model 26: 1971 Model 25 engine testbed conversion
- Model 26: 2 x 3,230 lbf Garrett AIResearch TFE731-2s
-- NB: N26GL was also referred to as Model 25BGF

Lear-Jet 28 - (Project) 1964-65 Lear Liner bizjet/airliner
- Model 28: Feederliner a/c or larger business jet
- Model 28: 4-abreast passenger seating, span 70.67 feet
- Model 28: 1964, 2 x 4.200 lbf GE CF700-2Bs (aft fan?)
- Model 28: 1965, 2 x 8,750 lbf Rolls-Royce Spey Juniors
-- Model 28 development eclipsed by longer Model 40 (qv)
-- https://www.secretprojects.co.uk/attachments/learjet_28-jpg.8201/

Learjet 28 (II) - 1979 2+8 pax Model 25 successor, x 5
- Model 28: Model 25 fuselage fitted with new wings
- Model 28: 2 x 2,950 lbf GE CJ610-8As, span 13.35 m
-- Branded as 'Longhorn'* due to winglets
-- * Basic turbojet member of Longhorn family
- Model 28: Learjet 28 production run 1979-1980

Learjet 29 - 1979 2+6 pax Model 25 successor, x 4
- Model 29: Long-range equivalent to Model 28
- Model 29: 2 x 2,950 lbf GE CJ610-8As, span 13.35 m
-- 'Longhorn'* due to supercritical winglets
-- Learjet 29 traded 2 x pax for 379 L fuel increase
-- * L-R turbojet member of Longhorn family
- Model 29: Learjet 29 production run 1979-1984

Learjet 31 - 1987 Model 35/36 w/ 'Longhorn' wing
- Model 31 : High speed/altitude, limited range, x 246
- Model 31 : 2 x 3,500 lbf Garrett TFE731-2s, span 13.36 m
- Model 31A: Updated repl. for Learjet 31 w/ EFIS cockpit
- Model 31A/ER: Extended range '31A variant, 3,539 km
- Learjet 31B: Typo/Google mis-return for 'Learjet 31A'
- Model 31: Learjet 31 production run 1987-2003

Learjet 35 - 1971 turbofan-powered Model 25B deriv., x 676
- Model 35 : Longer wings, 0.33 m fwd fuselage plug, x 64
- Model 35 : Stretch to increase passenger leg room
- Model 35 : 2 x 3,500 lbf Garrett TFE731-2s, span 12.04 m
- Model 35A: 1976, TFE731-2Bs, Century III wing, x 612
- Learjet 35B: Typo/Flight Aware return for 'Learjet 35A'
-- C-21A : USAF desig.; for pax, cargo, & medevac, x 84
-- U-35 : Força Aérea Brasileira (FAB) utility transport
-- VU-35: FAB VIP transp. (Grupo de Transporte Especial)
-- R-35AM: FAB ELINT/SIGINT variant, sometimes 'RC-35AM'

Learjet 36 - 1974 extended-range version of Model 35, x 63
- Model 36 : 13 inch stretch to increase leg room, x 17
- Model 36 : 2 x Garrett TFE731-2 turbofans
- Model 36: 2 x 3,500 lbf Garrett TFE 731-2s, span 12.04 m
- Model 36A: 1976, TFE731-2Bs, Century III wing, x 46
- Model 36B: Reported as ELINT variant used by Peru [1]
-- U-36A: Japanese Maritime Self-Defense Force 9203-9206
-- U-36A: JMSDF Learjet 36A multi-purpose military a/c*
-- * Target-tug, sea-skimming missile simulation, ECM
-- * U-36A: Belly surveillance radar, jammer/ECM pods
-- * NB: 'U-36' seen, sometimes mistaken for a variant
- Model 36: Production 1974-1975, Learjet 36A 1976-1986

Lear-Jet 40 (I) - (Project) 1965 Lear Liner feederliner a/c
- Model 40: 15 foot fuselage stretch over Model 28 (qv)
- Model 40: 4-abreast passenger seating, span 70.67 feet
- Model 40: 2 x 11,400 lbf R-R Spey 25s/Mk 511-14W
--
Learjet 40 (II) - 2002 Learjet 31A repl. based on Learjet 45
- Model 40 : Learjet 45 with fuselage shortened 60 cm, x 127
- Model 40 : 2 x 3,500 lbf Honeywell TFE731-20AR, span 14.56 m
- Model 40XR: 2004 upgrade, higher MTOW, faster cruise/climb, x 7
- Model 40XR: 2 x 3,500 lbf Honeywell TFE731-20BR turbofans
- Model 40: Production 2002-2013, 40XR 2007-2011

Learjet 45 - 1995 mid-sized 'super-light' business jet, x 458
- Model 45: 1st 'clean sheet' design Learjet since Model 23
- Model 45 : 2 x 3,650 lbf Honeywell TFE731-20s, span 14.58 m
- Model 45XR: 2004 upgrade, higher MTOW, faster cruise/climb
- Model 45XR: 2 x flat-rated 3,500 lbf TFE731-20BR turbofans
- Model 45: Production 1995–2013 (454), '45XR 2004-2012 (4)

Learjet 54 - (Project) 1977 11-seat Model 50 series member
- Model 54: Longer, incr. diameter fuselage, longer wings*
- Model 54: 2 x 3,650 lbf Garrett TFE 731-3-100B, span 13.35 m
-- * 'Longhorn' winglets as on Learjet Models 28 and 29
- Model 54: Fuselage as per '55, differed in internal arrang.

Learjet 55 - 1981 50 Series production model Honeywell TFE731
- Model 55 : 1981 prod'n (incl. extended-range 55ER), x 126
- Model 55 : 2 x 3,700 lbf Garret TFE 731-3A-2B; span 13.35 m
- Model 55LR: Longer-Range version (than 'ER), aka 'LR-55'
-- LR carries 3,495 kg fuel, ER 3,197 kg, 55 carries 3,042 kg
- Model 55Plus: Perf. version, higher MTOW, larger brakes
- Model 55B: 1986, glass cockpit, impr. TO, 2,040 nm range, x 8
- Model 55C: 1987, 2 x 3,700 lbf TFE 731-3AR turbofan engines
-- Model 55C intro'd 'Delta Fins', reduced landing speed, x 14
- Model 55C-ER: Extended-Range version of the Learjet 55C
-- Learjet 55C/LR: Wiki listing, conf. with ICAO LR55C code?
- Model 55D: (??) typo?
-- U-55C: Força Aérea Brasileira (FAB) utility transport
- Model 55 : Produced 1979–1987, x 147

Learjet 56 - (Project) 1977 8-seat Model 50 series member
- Model 56: Shorter fuselage compared with Learjet 55*
- Model 54: 2 x 3,650 lbf Garrett TFE 731-3-100B, span 13.35 m
-- * With reduced pax permitting more fuel and a longer range

Learjet 60 - 1991 improved, re-engined vers. of Learjet 55
- Model 60 : 2+4, stretched, Pratt & Whitney Canada engines
- Model 60 : 2 x 4,600 lbf P&WC PW305As, span 13.34 m
- Model 60 : Production 1991-2007, x 316 deliveries
- Model 60XR: 2007 2+7, upgraded cabin, advanced avionics
- Model 60XR: Production 2005-2013, x 114 deliveries

Learjet 65 - (??) typo for LJ75, LJ85, poss. 60XR confusion
-- Seems mainly to be Learjet 75 or 85 typo, eg: 2013 mockup
-- Some online conf. stems from Learjet 60 60-243 reg. N65LJ
-- https://www.ledevoir.com/economie/4...tique-annonce-qu-elle-supprimera-1000-emplois
-- https://www.airliners.net/photo/Untitled/Learjet-65-Mock-up/2284855

Learjet 70 - 2013 mid-sized bizjet, Learjet Model 40XR upgrade
- Model 70: 6 pax, Model 40XR w/ aerodynamic impr., winglets
- Model 70: 2 x 3,850 lbf Honeywell TFE731-40BR, span 13.96 m
- Model 70: Comp/ w/ '40XR, flat floor and cabin height incr.
- Model 70: Production 2013-2015, x 13

Learjet 75 - 2013 mid-sized bizjet, Learjet Model 45XR upgrade
- Model 75: 8 pax, Model 45XR w/ aerodynamic impr., winglets
- Model 75: 2 x 3,850 lbf Honeywell TFE731-40BR, span 13.96 m
- Model 75: Comp/ w/ '45XR, flat floor and cabin height incr.
- Model 75: Production 2013-2020, x 130

Learjet 80 - (??) Speculative desig. for short-fuselage LJ85
- Model 80: Poss. desig. for planned 2012-13 LJ85 derivative
-- https://www.flightglobal.com/bombardier-hints-at-scaled-down-version-of-learjet-85/107093.article

Learjet 85 - 2014 mid-sized composite airframe bizjet, x 2*
- Model 85 : 2+8, fit between mid- and 'super mid-sized'
- Model 85 : 2 x 6,100 lbf P&WC PW307Bs, span 18.75 m**
- Learjet NXT: Original designation for LJ85 programme
-- Composite airframe, wings sim. to CSeries [2]
- Model 85: Flight Test Vehicle 1 (FTV1) flew April 2014
-- * FTV2 fuselage integrated Nov. 2012, ever completed?
-- * Were to be 3 x prototypes to be assembled by Grob [3]
-- ** Some sources list 5,262 lbf as being PW307B output
- Project begun Oct 2007, paused Jan 2015, canc. Oct 2015

____________________________________________

[1] 'Il futuro delle Forze Armate Peruviane', RID Rivista italiana difesa N.12, 12/2016, pp. 76-78.

[2] Learjet 85 had a 9.75 m pressure fuselage shell, which was created in an out-of-autoclave process in Querétaro, Mexico. The wing, composed of a composite shell over steel frames, was made in Belfast. Final assembly was by Learjet in Wichita.

[3] In Jan 2008, Bombardier announced that German-Swiss Grob Aerospace AG would design and construct three Learjet 85 prototypes. By Aug 2008, Grob was insolvent. On 18 Sept 2008, Bombardier announced that it was dropping Grob as Learjet 85 prototype maker.
 
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