Learjet 24#Aircraft on display

{{Infobox aircraft

|name = Learjet 24

|image = NASA DFRC Lear 24 in flight.jpg

|caption = NASA Learjet 24

|type = Business jet

|manufacturer = Learjet

|designer =

|first_flight = January 24, 1966

|introduction = November 9, 1966

|retired =

|status = Active

|primary_user =

|more_users =

|produced = 1966–1977

|number_built = 259

|unit cost =

}}

The Learjet 24 is an American six-to-eight-seat (two crew and four to six passengers) twin-engine, high-speed business jet, which was manufactured by Learjet as the successor to the Learjet 23.

History

File:Lear Jet 24B F-BUFN Athens 22.04.73 edited-3.jpg

The Learjet 24 was designed as an improved version of the Learjet 23, which was limited to {{convert|12500|lb}} gross weight. Engineers designed the model 24 to accept up to the full {{convert|13500|lb}} gross weight permitted by FAR-25 standards.

Other improvements introduced in the Learjet 24 included:

increased cabin pressurization, to allow a higher operating altitude
the addition of one extra window on the right side of the cabin
more powerful engines
a new windshield
auxiliary fuel in wing tip tanks
a fire-extinguishing system for the engines

With these changes, the LJ24 became the first business jet to be certified under FAR-25.{{Cite web |url=http://www.wingsoverkansas.com/history/article.asp?id=199 |title=Learjet company timeline |access-date=2007-01-08 |archive-url=https://web.archive.org/web/20061231131658/http://www.wingsoverkansas.com/history/article.asp?id=199 |archive-date=2006-12-31 |url-status=dead }}

The first flight of a Learjet 24 took place on January 24, 1966. From May 23 to 26, 1966, a Learjet 24 flew around the world in 50 hours and 20 minutes flying time as a demonstration of its capabilities.

Different variants were the 24A, B, C, D, E and F, with changes of takeoff weight, in-fuselage fuel tank, range, cabin and engines.

Altogether 259 Model 24s were built, and in 2001, there were still 210 Learjet 24s in use. Thirty-nine LJ24s have been lost through accidents.

Noise compliance

In 2013, the FAA modified 14 CFR part 91 rules to prohibit the operation of jets weighing 75,000 pounds or less that are not stage 3 noise compliant after December 31, 2015. The Learjet 24 is listed explicitly in Federal Register [http://www.gpo.gov/fdsys/granule/FR-2013-07-02/2013-15843/content-detail.html 78 FR 39576]. Any Learjet 24s that have not been modified by installing Stage 3 noise compliant engines or have not had "hushkits" installed for non-compliant engines will not be permitted to fly in the contiguous 48 states after December 31, 2015. 14 CFR §91.883 Special flight authorizations for jet airplanes weighing 75,000 pounds or less – lists special flight authorizations that may be granted for operation after December 31, 2015.

Variants

=Learjet 24A=

Standard version. Converted from existing Learjet 23. Takeoff weight {{convert|13499|lb}}. FAA certified on November 9, 1966. 81 aircraft built.

=Learjet 24B=

Improved variant, powered by two {{convert|2950|lbf|kN|abbr=on}} thrust General Electric CJ610-6 turbojet engines, and {{convert|13499|lb}} maximum take-off weight. FAA certified December 17, 1968. 49 aircraft built.

=Learjet 24C=

A light-weight version of the 24B, fuselage tank not fitted which would have caused a reduction in range. The Learjet 24C project was abandoned in December 1970. Take-off weight {{convert|5675|kg}}. None built.

=Learjet 24D=

Similar to Learjet 24C, however by changing surface tanks range and takeoff weight were increased to {{convert|6129|kg}}. Round cabin windows replaced by angular. FAA certified July 17, 1970. Replaced the 24B in production. A reduced gross weight (restricted to {{convert|12500|lb}} version was also available (the 24D/A). 99 built.

=Learjet 24D/A=

Light-weight version with a restricted take-off weight of 5,669 kg (12,500 lb).

=Learjet 24E and 24F=

Two new versions were announced in 1976 the 24E and 24F, they introduced a new cambered wing and aerodynamic improvements to reduce stall and approach speed (Century III wing). The 24E did not have a fuselage fuel tank for higher payload but shorter range. Some 24E models had the fuselage tank installed later to restore range. Powered by two {{convert|2950|lbf|kN|abbr=on}} thrust General Electric CJ610-8A turbojet engines. On April 15, 1977, the FAA approved extended ceiling to {{convert|51000|ft}}, the highest level then achieved in civilian aviation. 29 aircraft built.

Operators

Mainly used by private individuals and corporations, one aircraft was used by NASA as the {{ill|Learjet Observatory|de|Lear Jet Observatory}}.

Accidents and incidents

On January 6, 1977, Dolly Sinatra, the mother of Frank Sinatra, was one of four killed when Learjet 24 N12MK crashed into a mountain following a departure from Palm Springs Airport, United States.{{cite web |url=https://aviation-safety.net/database/record.php?id=19770106-1 |title = ASN Aircraft accident Learjet 24B N12MK Palm Springs, CA}}{{Cite news |date=10 January 1977 |title=Body of Sinatra's Mother Found at Crash Site |url=https://www.nytimes.com/1977/01/10/archives/body-of-sinatras-mother-found-at-crash-site.html |access-date=1 April 2024 |work=The New York Times}}{{Cite web |title=LAX77AA019 |url=https://www.ntsb.gov/Pages/brief.aspx?ev_id=55869&key=0 |access-date=7 April 2024 |website=National Transportation Safety Board}}

Aircraft on display

File:Learjet 24 sn131 at Wings Over the Rockies Museum.jpg

055 – Learjet 24 on static display at the Tillamook Air Museum in Tillamook, Oregon.{{cite web|title=Aircraft|url=http://www.tillamookair.com/aircraft|website=Tillamook Air Museum|accessdate=8 November 2016}}{{cite news|title=Tillamook Air Museum keeps changing to display history|url=http://www.tillamookheadlightherald.com/news/tillamook-air-museum-keeps-changing-to-display-history/article_15fba608-1eb2-11e6-98f5-cb00c7cc41c3.html|accessdate=8 November 2016|work=Tillamook Headlight Herald|date=20 May 2016}}{{cite web|last1=Olsen|first1=Eric|title=Aircraft N711CW Photo|url=http://www.airport-data.com/aircraft/photo/001160973.html|website=Airport-Data.com|accessdate=8 November 2016|date=29 December 2015}}
24-131 – Learjet 24 on static display at Wings Over the Rockies Air and Space Museum in Denver, Colorado.{{cite news|last1=Lips|first1=Jesse|title=Growing Wings Family Fuels Progress And Promise|url=http://airportjournals.com/growing-wings-family-fuels-progress-and-promise|accessdate=8 November 2016|work=Airport Journals|publisher=AIRPORT JOURNALS|date=1 April 2006}}
193 – Learjet 24B on display at the Dakota Territory Air Museum in Minot, North Dakota.{{cite news |last1=Skurzewski |first1=Joe |title=Don Bessette donates 1969 jet to Minot's air museum |url=http://www.kfyrtv.com/content/news/Don-Bessette-donates-1969-jet-to-Minots-air-museum-486885281.html |accessdate=23 July 2019 |work=West Dakota FOX |date=28 June 2018}}{{cite web |title=FAA REGISTRY [N193DB] |url=http://registry.faa.gov/aircraftinquiry/NNum_Results.aspx?NNumbertxt=193DB |website=Federal Aviation Administration |publisher=U.S. Department of Transportation |accessdate=23 July 2019 }}{{Dead link|date=November 2024 |bot=InternetArchiveBot |fix-attempted=yes }}
203 – Learjet 24B on static display at the Evergreen Aviation & Space Museum in McMinnville, Oregon.{{cite web|title=General Aviation|url=http://www.evergreenmuseum.org/general-aviation|website=Evergreen Museum Campus|publisher=Evergreen Museum|accessdate=8 November 2016|archive-date=3 October 2016|archive-url=https://web.archive.org/web/20161003044600/http://www.evergreenmuseum.org/general-aviation|url-status=dead}}{{cite web|last1=Brandt|first1=Hanna|title=ARTIFACT PICK OF THE WEEK: LEARJET 24|url=http://www.evergreenmuseum.org/artifact-pick-of-the-week-learjet-24|website=Evergreen Museum Campus|publisher=Evergreen Museum|accessdate=8 November 2016|date=23 January 2014}}
281 – Learjet 24D on display at the Frontiers of Flight Museum in Dallas, Texas.{{cite web|title=Learjet Model 24D|url=http://www.flightmuseum.com/exhibits/aircraft-3/learjet-model-24d|website=Frontiers of Flight Museum|accessdate=8 November 2016|archive-url=https://web.archive.org/web/20161129100639/http://www.flightmuseum.com/exhibits/aircraft-3/learjet-model-24d/|archive-date=29 November 2016|url-status=dead}}
Learjet 24D on display at ITE College Central
163 - Learjet 24F on display at Lewis University in Romeoville, Illinois. Formerly owned by Arnold Palmer from 1968-1976. Donated to Lewis By Waste Management in 1986 for use by maintenance students in their Aviation Department.

Specifications (Learjet 24F)

File:Learjet 24 3-View line art.gif

{{Aircraft specs

|ref=Jane's All The World's Aircraft 1976–77Taylor 1976, pp. 283–284.

|prime units?=imp

|genhide=

|crew= Two (pilot & co-pilot)

|capacity=6 passengers

|length m=

|length ft=43

|length in=3

|span m=

|span ft=35

|span in=7

|span note= (over tip-tanks)

|height m=

|height ft=12

|height in=3

|wing area sqm=

|wing area sqft=231.77

|aspect ratio=5.01:1

|airfoil=NACA 64A109

|empty weight kg=

|empty weight lb=7130

|gross weight kg=

|max takeoff weight lb=13500

|fuel capacity={{convert|840|USgal|impgal L|abbr=on}}

|eng1 number=2

|eng1 name=General Electric CJ610-6

|eng1 type=turbojets

|eng1 kn=

|eng1 lbf=2950

|perfhide=

|max speed kmh=

|max speed mph=545

|max speed kts=

|max speed note=at {{convert|31000|ft|m|abbr=on}}

Never exceed speed: Mach 0.86

|cruise speed kmh=

|cruise speed mph=481

|cruise speed note=at {{convert|45000|ft|m|abbr=on}} (econ cruise)

|stall speed mph=100

|stall speed note= (gear and flaps down) - IAS

|range km=

|range miles=1695

|range nmi=

|range note=4 passengers, max fuel, 45 min reserves

|ceiling m=

|ceiling ft=45000

|climb rate ms=

|climb rate ftmin=6800

|more performance=*Takeoff length to 35 ft (11 m): {{convert|2800|ft|m|abbr=on}}

Landing distance from 50 ft (15 m): {{convert|2450|ft|m|abbr=on}}

|avionics=

}}

References

;Notes

;Bibliography

Taylor, John W. R. Jane's All The World's Aircraft 1976–77. London:Jane's Yearbooks, 1976. {{ISBN|0-354-00538-3}}.

External links

[http://www.airliners.net/info/stats.main?id=264 A history of the LJ23-LJ29 series on Airliners.net] – not to be reached 5 October 2016
[http://aviation-safety.net/database/dblist.php?Type=LJ-24 Listing of LJ24 accidents in ASN Aviation Safety Database]

Category:1960s United States business aircraft

Category:Twinjets

Category:T-tail aircraft

Category:Aircraft first flown in 1966

Category:Low-wing aircraft

Category:Aircraft with retractable tricycle landing gear